SN-LABELING AND RADIOLABELING OF EPICHAPEROME INHIBITORS

RELATED APPLICATIONS

This application claims the benefit under 35 U.S.C. § 119 of United States Provisional Application Serial Number 63/153,123, filed February 24, 2021, the entire contents of which are incorporated herein by reference.

BACKGROUND

The Hsp90 family of proteins has four recognized members in mammalian cells: Hsp90-alpha (a) and -beta (b), GRP94 and TRAP-1. Hsp90-alpha and -beta exist in the cytosol and the nucleus in association with many other proteins. The Hsp90 family collectively represents the most abundant cellular chaperones, and it has been proposed to function in several beneficial ways including for example as part of the cellular defense against stress such as exposure to heat or other environmental stress. However, it has also been postulated to facilitate the stability and function of mutated proteins such as for example mutated p53. Under extreme or chronic stress Hsp90 has also been found to form tight complexes, called epichaperomes, with other chaperones and regulatory proteins. Many diseased cells are dependent on epichaperome function thus epichaperomes have been identified as putative targets of therapeutic agents.

SUMMARY

Aspects of this disclosure provide new and improved methods for preparing radiolabeled inhibitors of Hsp90, Hsp90 isoforms and Hsp90 homologs. These radiolabeled inhibitors are referred to herein as radiolabeled Hsp90 inhibitors or radiolabeled epichaperome inhibitors. They are able to bind selectively to Hsp90 including Hsp90 isoforms and homologs when these proteins are complexed in an epichaperome.

Radiolabeled Hsp90 inhibitors have numerous clinical applications including in situ visualization of on-target and off-target inhibitor localization and Hsp90 inhibitor metabolism and pharmacokinetics. Such applications may be used to diagnose disease in addition to informing personalized treatment regimens for patients.

More specifically, this disclosure is premised, in part, on the unexpected finding that peracetic acid and a particular ratio of chloramine-T to Hsp90 inhibitor substrate can be used to produce radiolabeled Hsp90 inhibitors at a high purity and yield. This disclosure is also premised, in part, on the unexpected finding that use of tris(dibenzylideneacetone)dipalladium(0) (Pd ₂ (dba) ₃ ) as a catalyst to produce tin (Sn)-labeled precursors results in a more robust production method. In some instances, the use of this particular compound as a catalyst reduces reaction stalling and/or improves catalyst turnover. Existing methods for producing radiolabeled Hsp90 inhibitors and precursors thereof including Sn-labeled precursors, often result in reaction stalling and require additional charges of reagents. Aspects of the present disclosure in contrast provide improved methods of producing radiolabeled Hsp90 inhibitors and precursors thereof including Sn-labeled Hsp90 inhibitors having reduced stalling propensity. These claimed methods are therefore more robust and efficient than prior art methods. Reduced stalling propensity may manifest itself as a reduced requirement for catalyst charging or no requirement for catalyst charging at all.

Aspects of the present disclosure provide methods of producing a compound of Formula II: (Formula II) or a pharmaceutically acceptable salt thereof, comprising reacting: a compound of Formula I: (Formula I) or a pharmaceutically acceptable salt thereof with a radioiodine salt in the presence of peracetic acid in a solution at a pH between 2-5, thereby forming a reaction mixture, wherein:

W is a radioiodine; X is — CH ₂ — — O— , or — S— ;

Y ¹ and Y ² are independently =CR ^3a — or =N — , as valency permits;

Z ¹ , Z ² , and Z ³ are independently — CH= or — N=, as valency permits;

R ¹ is hydrogen or halogen;

L is a straight or branched, C _2-14 aliphatic group wherein one or more carbons are optionally and independently replaced by -Cy-, — N(R)C(O) — , — C(O)N(R) — , — C(O)N(O) — , — N(R) SO _2— , — SO ₂ N(R)— , — O— , — C(O)— , — OC(O)— , — C(O)O— , — S — , — SO — , or — SO ₂ — , or wherein one or more carbons are independently replaced by — NR — , wherein R is not a -Boc protecting group in L; each -Cy- is independently an optionally substituted 3-8 membered bivalent, saturated, partially unsaturated, aryl ring, or heteroaryl ring having 1-4 heteroatoms independently selected from nitrogen, oxygen, or sulfur, or an optionally substituted 8-10 membered bivalent saturated, partially unsaturated, aryl bicyclic ring, or heteroaryl bicyclic ring having 1-5 heteroatoms independently selected from nitrogen, oxygen, or sulfur;

R ² is hydrogen or an optionally substituted group selected from the group consisting of C _1-6 aliphatic, phenyl, 3- to 7-membered saturated or partially unsaturated monocyclic carbocyclyl, 3- to 7-membered saturated or partially unsaturated monocyclic heterocyclyl having 1-2 heteroatoms selected from oxygen, nitrogen, or sulfur, 5- to 6-membered heteroaryl having 1-4 heteroatoms selected from oxygen, nitrogen, or sulfur, 7- to 10- membered saturated or partially unsaturated bicyclic carbocyclyl, 7- to 10-membered saturated or partially unsaturated bicyclic heterocyclyl having 1-4 heteroatoms selected from oxygen, nitrogen, or sulfur, 7- to 10-membered bicyclic heteroaryl having 1-4 heteroatoms selected from oxygen, nitrogen, or sulfur, or 8- to 10-membered bicyclic aryl; each R ³ is independently halogen, — NO ₂ , — CN, — OR, — SR, — N(R) ₂ , — C(O)R, — CO ₂ R, — C(O)C(O)R, — C(O)CH ₂ C(O)R, — S(O)R, — S(O) ₂ R, — C(O)N(R) ₂ , — SO ₂ N(R) ₂ , — OC(O)R, — N(R)C(O)R, — N(R)N(R) ₂ , or optionally substituted C _1-6 aliphatic or pyrrolyl; or two R ³ groups are taken together with their intervening atoms to form Ring A, wherein Ring A is an optionally substituted 3- to 7-membered partially unsaturated carbocyclyl, optionally substituted phenyl, an optionally substituted 5- to 6-membered partially unsaturated monocyclic heterocyclyl having 1-2 heteroatoms selected from oxygen, nitrogen, or sulfur; or an optionally substituted 5- to 6-membered heteroaryl having 1-4 heteroatoms selected from oxygen, nitrogen, or sulfur, or 6-membered aryl;

R ^3a is R ³ or hydrogen; R ⁴ is C _1-4 alkyl; each R is independently hydrogen or an optionally substituted group selected from C _{1- 6} aliphatic, phenyl, 3- to 7-membered saturated or partially unsaturated carbocyclyl, 3- to 7- membered saturated or partially unsaturated monocyclic heterocyclyl having 1-2 heteroatoms selected from oxygen, nitrogen, or sulfur, or 5- to 6-membered heteroaryl having 1-4 heteroatoms selected from oxygen, nitrogen, or sulfur, or: two R groups on the same nitrogen are taken together with their intervening atoms to form an optionally substituted ring selected from 3- to 7-membered saturated or partially unsaturated monocyclic heterocyclyl having 1-2 heteroatoms selected from oxygen, nitrogen, or sulfur, or 5- to 6-membered heteroaryl having 1-4 heteroatoms selected from oxygen, nitrogen, or sulfur, thereby producing a compound of Formula II or a pharmaceutically acceptable salt thereof. In some embodiments, the compound of Formula II or the pharmaceutically acceptable salt thereof is a compound of Formula III or a pharmaceutically acceptable salt thereof or of Formula IV, or a pharmaceutically acceptable salt thereof: (Formula III) or a pharmaceutically acceptable salt thereof; or

(Formula IV) or a pharmaceutically acceptable salt thereof.

In some embodiments, the compound of Formula I or the pharmaceutically acceptable salt thereof is Compound 1 or a pharmaceutically acceptable salt thereof or Compound 2 or a pharmaceutically acceptable salt thereof: (Compound 2) or a pharmaceutically acceptable salt thereof; or

(Compound 1) or a pharmaceutically acceptable salt thereof.

In some embodiments, the compound of Formula I is provided as a free base. In some embodiments, the compound of Formula I is provided as a hydrogen iodide salt (HI).

In some embodiments, the compound of Formula I or the pharmaceutically acceptable salt thereof is reacted with a radioiodine sodium salt. In some embodiments, the radioiodine or salt thereof is selected from I ¹²³ , I ¹²⁴ , or I ¹³¹ or a salt thereof.

In some embodiments, the compound of Formula II or a pharmaceutically acceptable salt thereof and/or the compound of Formula I or the pharmaceutically acceptable salt thereof is a good manufacturing practices (GMP) grade compound.

In some embodiments, the solution comprises about 0.1 to about 1 M (e.g., 0.1-1 M) phosphoric acid (H ₃ PO ₄ ) or sulfuric acid and water and the reaction occurs between about 15 to about 30 °C (e.g., 15-30 °C) for about 0.5 to about 1.5 minutes (e.g., 0.5- 1.5 minutes). In some embodiments, the solution comprises about 0.8 M phosphoric acid (H ₃ PO ₄ ) and water. In some embodiments, the reaction occurs between about 20 °C to about 30 °C for about 0.5 to about 1.5 minutes, including about 1 minute.

In some embodiments, the method further comprises adding, to the reaction mixture, sodium metabisulfite in saturated sodium bicarbonate (NaHCO ₃ ) following the reaction.

In some embodiments, the peracetic acid is about 3% to about 10% peracetic acid. In some embodiments, the peracetic acid is about 6% to about 7% peracetic acid, including about 6.3%, about 6.4% and about 6.5% peracetic acid.

In some embodiments, the method further comprises purifying the compound of Formula II or a pharmaceutically acceptable salt thereof from the reaction mixture.

In some embodiments, the compound of Formula II or a pharmaceutically acceptable salt thereof is recovered at about 80%, about 85%, about 90%, or about 95% yield. In some embodiments, the specific activity of the compound of Formula II or a pharmaceutically acceptable salt thereof is at least 10 mCi/mg, at least 20 mCi/mg, at least 30 mCi/mg, or at least 40 mCi/mg. Further aspects of the disclosure provide methods of producing a compound of

Formula II: (Formula II) or a pharmaceutically acceptable salt thereof, comprising reacting:

(a) a compound of Formula I: (Formula I) or a pharmaceutically acceptable salt thereof;

(b) chloramine-T; and

(c) a radioiodine salt, wherein the ratio of the mass of chloramine-T to the mass of the compound of Formula I or the pharmaceutically acceptable salt thereof in the reaction is about 3 to about 5, thereby forming a reaction mixture, wherein:

W is a radioiodine;

X is — CH ₂ — , — O— , or — S— ;

Y 1 and Y2 are independently =CR3a — or =N — , as valency permits;

Z1, Z2, and Z3 are independently — CH= or — N=, as valency permits;

R ¹ is hydrogen or halogen; L is a straight or branched, C _2-14 aliphatic group wherein one or more carbons are optionally and independently replaced by -Cy-, — N(R)C(O) — , — C(O)N(R) — , —

C(O)N(O) — , — N(R)SO _2— , — SO ₂ N(R)— , — O— , — C(O)— , — OC(O)— , — C(O)O— , — S — , — SO — , or — SO ₂ — , or wherein one or more carbons are independently replaced by — NR — , wherein R is not a -Boc protecting group in L; each -Cy- is independently an optionally substituted 3-8 membered bivalent, saturated, partially unsaturated, aryl ring, or heteroaryl ring having 1-4 heteroatoms independently selected from nitrogen, oxygen, or sulfur, or an optionally substituted 8-10 membered bivalent saturated, partially unsaturated, aryl bicyclic ring, or heteroaryl bicyclic ring having 1-5 heteroatoms independently selected from nitrogen, oxygen, or sulfur;

R ² is hydrogen or an optionally substituted group selected from the group consisting of C _1-6 aliphatic, phenyl, 3- to 7-membered saturated or partially unsaturated monocyclic carbocyclyl, 3- to 7-membered saturated or partially unsaturated monocyclic heterocyclyl having 1-2 heteroatoms selected from oxygen, nitrogen, or sulfur, 5- to 6-membered heteroaryl having 1-4 heteroatoms selected from oxygen, nitrogen, or sulfur, 7- to 10- membered saturated or partially unsaturated bicyclic carbocyclyl, 7- to 10-membered saturated or partially unsaturated bicyclic heterocyclyl having 1-4 heteroatoms selected from oxygen, nitrogen, or sulfur, 7- to 10-membered bicyclic heteroaryl having 1-4 heteroatoms selected from oxygen, nitrogen, or sulfur, or 8- to 10-membered bicyclic aryl; each R ³ is independently halogen, — NO ₂ , — CN, — OR, — SR, — N(R) ₂ , — C(O)R,

— CO ₂ R, — C(O)C(O)R, — C(O)CH ₂ C(O)R, — S(O)R, — S(O) ₂ R, — C(O)N(R) ₂ , — SO ₂ N(R) ₂ , — OC(O)R, — N(R)C(O)R, — N(R)N(R) ₂ , or optionally substituted C _1-6 aliphatic or pyrrolyl; or two R ³ groups are taken together with their intervening atoms to form Ring A, wherein Ring A is an optionally substituted 3- to 7-membered partially unsaturated carbocyclyl, optionally substituted phenyl, an optionally substituted 5- to 6-membered partially unsaturated monocyclic heterocyclyl having 1-2 heteroatoms selected from oxygen, nitrogen, or sulfur; or an optionally substituted 5- to 6-membered heteroaryl having 1-4 heteroatoms selected from oxygen, nitrogen, or sulfur, or 6-membered aryl;

R ^3a is R ³ or hydrogen;

R ⁴ is C _1-4 alkyl; each R is independently hydrogen or an optionally substituted group selected from C _{1- 6} aliphatic, phenyl, 3- to 7-membered saturated or partially unsaturated carbocyclyl, 3- to 7- membered saturated or partially unsaturated monocyclic heterocyclyl having 1-2 heteroatoms selected from oxygen, nitrogen, or sulfur, or 5- to 6-membered heteroaryl having 1-4 heteroatoms selected from oxygen, nitrogen, or sulfur, or: two R groups on the same nitrogen are taken together with their intervening atoms to form an optionally substituted ring selected from 3- to 7-membered saturated or partially unsaturated monocyclic heterocyclyl having 1-2 heteroatoms selected from oxygen, nitrogen, or sulfur, or 5- to 6-membered heteroaryl having 1-4 heteroatoms selected from oxygen, nitrogen, or sulfur, thereby producing a compound of Formula II or a pharmaceutically acceptable salt thereof. In some embodiments, the compound of Formula II or the pharmaceutically acceptable salt thereof is a compound of (Formula III) or a pharmaceutically acceptable salt thereof; or a compound of (Formula IV) or a pharmaceutically acceptable salt thereof. In some embodiments, the compound of Formula I or the pharmaceutically acceptable salt thereof comprises: (Compound 2) or a pharmaceutically acceptable salt thereof; or (Compound 1) or a pharmaceutically acceptable salt thereof.

In some embodiments, the compound of Formula I is provided as a free base.

In some embodiments, the compound of Formula I or the pharmaceutically acceptable salt thereof is reacted with a radioiodine sodium salt.

In some embodiments, the reaction further comprises phosphate buffer at about pH 7.

In some embodiments, the radioiodine or salt thereof is I ¹²³ , I ¹²⁴ , or I ¹³¹ or a salt thereof. In some embodiments, the compound of Formula II or a pharmaceutically acceptable salt thereof and/or the compound of Formula I or the pharmaceutically acceptable salt thereof and is a good manufacturing practices (GMP) grade compound.

In some embodiments, the yield of the compound of Formula II or the pharmaceutically acceptable salt thereof is at least 80%.

In some embodiments, the compound of Formula I or the pharmaceutically acceptable salt thereof is provided in ethanol.

In some embodiments, the compound of Formula I or the pharmaceutically acceptable salt thereof and chloramine-T are provided in a pre-mixed solution in acetic acid.

In some embodiments, the method further comprises passing the reaction mixture through a Sep-Pak and eluting the compound of Formula II with less than 3 mL of pure ethanol.

In some embodiments, the radioiodine salt is provided in about 0.01M NaOH. In some embodiments, the amount of radioiodine salt is between about 3 and about

3.5 mCi.

Further aspects of the present disclosure provide methods of producing a compound of Formula I: (Formula I) or a pharmaceutically acceptable salt thereof, comprising reacting in a reaction mixture: a compound of Formula V: (Formula V) or a pharmaceutically acceptable salt thereof with hexamethylditin (Sn ₂ Me ₆ ) and tris(dibenzylideneacetone)dipalladium(0) (Pd ₂ (dba) ₃ ) in a solution, thereby producing a compound of Formula I or a pharmaceutically acceptable salt thereof.

In some embodiments, the reaction occurs between about 60 °C to about 80 °C.

In some embodiments, the method further comprises purifying the compound of Formula I.

In some embodiments, purifying the compound of Formula I comprises mixing the compound of Formula I with dichloromethane (DCM) and stirring the mixture to form a substantially clear solution.

In some embodiments, the method further comprises adding purified water to the substantially clear solution, stirring the solution for at least 5 minutes, and allowing the solution to separate into an organic layer and an aqueous layer.

In some embodiments, the method further comprises adding purified water, mixing the layers for at least 15 minutes, and allowing the layers to separate. In some embodiments, the method further comprises further adding purified water, mixing the layers for at least 15 minutes, and allowing the layers to separate.

In some embodiments, the method further comprises filtering the organic layer, washing the reaction vessel with DCM, and concentrating the filtrate and the wash.

In some embodiments, the concentrating occurs at no more than 50 °C to distill the compound of Formula I.

In some embodiments, the compound of Formula I is further dried under vacuum at no more than 70 °C.

In some embodiments, the compound of Formula V or the pharmaceutically acceptable salt thereof and/or the compound of Formula I or the pharmaceutically acceptable salt thereof is a good manufacturing practices (GMP) grade compound.

In some embodiments, the method further comprises adding ethanol (EtOH)-Heptane to the compound of Formula I.

In some embodiments, the compound of Formula I or the pharmaceutically acceptable salt thereof comprises:

(Compound 2) or a pharmaceutically acceptable salt thereof; or (Compound 1) or a pharmaceutically acceptable salt thereof.

In some embodiments, the compound of Formula V or the pharmaceutically acceptable salt thereof comprises:

Compound 6:

or a pharmaceutically acceptable salt thereof; or

Compound 7 : or a pharmaceutically acceptable salt thereof.

Further aspects of the present disclosure provide kits comprising: (i) a compound of Formula I: (Formula I) or a pharmaceutically acceptable salt thereof;

(ii) phosphoric acid (H ₃ PO ₄ ); and

(iii) peracetic acid, wherein:

X is — CH ₂ — — O— , or — S— ;

Y ¹ and Y ² are independently =CR ^3a — or =N — , as valency permits;

Z ¹ , Z ² , and Z ³ are independently — CH= or — N=, as valency permits;

R ¹ is hydrogen or halogen;

L is a straight or branched, C2-14 aliphatic group wherein one or more carbons are optionally and independently replaced by -Cy-, — N(R)C(O) — , — C(O)N(R) — , — C(O)N(O) — , — N(R)SO _2— , — SO ₂ N(R)— , — O— , — C(O)— , — OC(O)— , — C(O)O— , — S — , — SO — , or — SO ₂ — , or wherein one or more carbons are independently replaced by — NR — , wherein R is not a -Boc protecting group in L; each -Cy- is independently an optionally substituted 3-8 membered bivalent, saturated, partially unsaturated, aryl ring, or heteroaryl ring having 1-4 heteroatoms independently selected from nitrogen, oxygen, or sulfur, or an optionally substituted 8-10 membered bivalent saturated, partially unsaturated, aryl bicyclic ring, or heteroaryl bicyclic ring having 1-5 heteroatoms independently selected from nitrogen, oxygen, or sulfur;

R ² is hydrogen or an optionally substituted group selected from the group consisting of C _1-6 aliphatic, phenyl, 3- to 7-membered saturated or partially unsaturated monocyclic carbocyclyl, 3- to 7-membered saturated or partially unsaturated monocyclic heterocyclyl having 1-2 heteroatoms selected from oxygen, nitrogen, or sulfur, 5- to 6-membered heteroaryl having 1-4 heteroatoms selected from oxygen, nitrogen, or sulfur, 7- to 10- membered saturated or partially unsaturated bicyclic carbocyclyl, 7- to 10-membered saturated or partially unsaturated bicyclic heterocyclyl having 1-4 heteroatoms selected from oxygen, nitrogen, or sulfur, 7- to 10-membered bicyclic heteroaryl having 1-4 heteroatoms selected from oxygen, nitrogen, or sulfur, or 8- to 10-membered bicyclic aryl; each R ³ is independently halogen, — NO ₂ , — CN, — OR, — SR, — N(R) ₂ , — C(O)R, — CO ₂ R, — C(O)C(O)R, — C(O)CH ₂ C(O)R, — S(O)R, — S(O) ₂ R, — C(O)N(R) ₂ , — SO ₂ N(R) ₂ , — OC(O)R, — N(R)C(O)R, — N(R)N(R) ₂ , or optionally substituted C _1-6 aliphatic or pyrrolyl; or two R ³ groups are taken together with their intervening atoms to form Ring A, wherein Ring A is an optionally substituted 3- to 7-membered partially unsaturated carbocyclyl, optionally substituted phenyl, an optionally substituted 5- to 6-membered partially unsaturated monocyclic heterocyclyl having 1-2 heteroatoms selected from oxygen, nitrogen, or sulfur; or an optionally substituted 5- to 6-membered heteroaryl having 1-4 heteroatoms selected from oxygen, nitrogen, or sulfur, or 6-membered aryl; R ^3a is R ³ or hydrogen;

R ⁴ is C _1-4 alkyl; each R is independently hydrogen or an optionally substituted group selected from C _{1- 6} aliphatic, phenyl, 3- to 7-membered saturated or partially unsaturated carbocyclyl, 3- to 7- membered saturated or partially unsaturated monocyclic heterocyclyl having 1-2 heteroatoms selected from oxygen, nitrogen, or sulfur, or 5- to 6-membered heteroaryl having 1-4 heteroatoms selected from oxygen, nitrogen, or sulfur, or: two R groups on the same nitrogen are taken together with their intervening atoms to form an optionally substituted ring selected from 3- to 7-membered saturated or partially unsaturated monocyclic heterocyclyl having 1-2 heteroatoms selected from oxygen, nitrogen, or sulfur, or 5- to 6-membered heteroaryl having 1-4 heteroatoms selected from oxygen, nitrogen, or sulfur.

In some embodiments, the compound in (i) comprises: (Compound 2) or a pharmaceutically acceptable salt thereof; or

(Compound 1) or a pharmaceutically acceptable salt thereof.

In some embodiments, the kit further comprises a radioiodine salt. In some embodiments, the radioiodine salt is sodium radioiodine.

In some embodiments, the kit further comprises (iv) about 0.1 to about 1 M phosphoric acid (H ₃ PO ₄ ).

In some embodiments, the kit further comprises (iv) about 0.8 M phosphoric acid (H ₃ PO ₄ ). In some embodiments, the kit further comprises sodium metabisulfite in saturated sodium bicarbonate (NaHCO,).

In some embodiments, the peracetic acid is about 3% to about 10% peracetic acid.

In some embodiments, the peracetic acid is about 6% to about 7% peracetic acid, including about 6.3%, about 6.4% and about 6.5% peracetic acid. In some embodiments, the kit further comprises a syringe, Sep-Pak, and/or ethanol.

In some embodiments, the radioiodine salt is a salt of I ¹²³ , I ¹²⁴ , or I ¹³¹ .

Further aspects of the present disclosure provide kits comprising:

(i) a compound of Formula I: (Formula I) or a pharmaceutically acceptable salt thereof; and (ii) chloramine-T, wherein the ratio of the mass of chloramine-T to the mass of the compound of Formula I or the pharmaceutically acceptable salt thereof in the reaction is about 3 to about 5 and wherein:

X is — CH ₂ — — O— , or — S— ;

Y ¹ and Y ² are independently =CR ^3a — or =N — , as valency permits;

Z ¹ , Z ² , and Z ³ are independently — CH= or — N=, as valency permits;

R ¹ is hydrogen or halogen;

L is a straight or branched, C _2-14 aliphatic group wherein one or more carbons are optionally and independently replaced by -Cy-, — N(R)C(O) — , — C(O)N(R) — , — C(O)N(O) — , — N(R)SO _2— , — SO ₂ N(R)— , — O— , — C(O)— , — OC(O)— , — C(O)O— , — S — , — SO — , or — SO ₂ — , or wherein one or more carbons are independently replaced by — NR — , wherein R is not a -Boc protecting group in L; each -Cy- is independently an optionally substituted 3-8 membered bivalent, saturated, partially unsaturated, aryl ring, or heteroaryl ring having 1-4 heteroatoms independently selected from nitrogen, oxygen, or sulfur, or an optionally substituted 8-10 membered bivalent saturated, partially unsaturated, aryl bicyclic ring, or heteroaryl bicyclic ring having 1-5 heteroatoms independently selected from nitrogen, oxygen, or sulfur;

R ² is hydrogen or an optionally substituted group selected from the group consisting of C _1-6 aliphatic, phenyl, 3- to 7-membered saturated or partially unsaturated monocyclic carbocyclyl, 3- to 7-membered saturated or partially unsaturated monocyclic heterocyclyl having 1-2 heteroatoms selected from oxygen, nitrogen, or sulfur, 5- to 6-membered heteroaryl having 1-4 heteroatoms selected from oxygen, nitrogen, or sulfur, 7- to 10- membered saturated or partially unsaturated bicyclic carbocyclyl, 7- to 10-membered saturated or partially unsaturated bicyclic heterocyclyl having 1-4 heteroatoms selected from oxygen, nitrogen, or sulfur, 7- to 10-membered bicyclic heteroaryl having 1-4 heteroatoms selected from oxygen, nitrogen, or sulfur, or 8- to 10-membered bicyclic aryl; each R ³ is independently halogen, — NO ₂ , — CN, — OR, — SR, — N(R) ₂ , — C(O)R, — CO ₂ R, — C(O)C(O)R, — C(O)CH ₂ C(O)R, — S(O)R, — S(O) ₂ R, — C(O)N(R) ₂ , — SO ₂ N(R) ₂ , — OC(O)R, — N(R)C(O)R, — N(R)N(R) ₂ , or optionally substituted C _1-6 aliphatic or pyrrolyl; or two R ³ groups are taken together with their intervening atoms to form Ring A, wherein Ring A is an optionally substituted 3- to 7-membered partially unsaturated carbocyclyl, optionally substituted phenyl, an optionally substituted 5- to 6-membered partially unsaturated monocyclic heterocyclyl having 1-2 heteroatoms selected from oxygen, nitrogen, or sulfur; or an optionally substituted 5- to 6-membered heteroaryl having 1-4 heteroatoms selected from oxygen, nitrogen, or sulfur, or 6-membered aryl;

R ^3a is R ³ or hydrogen;

R ⁴ is C _1-4 alkyl; each R is independently hydrogen or an optionally substituted group selected from C _{1- 6} aliphatic, phenyl, 3- to 7-membered saturated or partially unsaturated carbocyclyl, 3- to 7- membered saturated or partially unsaturated monocyclic heterocyclyl having 1-2 heteroatoms selected from oxygen, nitrogen, or sulfur, or 5- to 6-membered heteroaryl having 1-4 heteroatoms selected from oxygen, nitrogen, or sulfur, or: two R groups on the same nitrogen are taken together with their intervening atoms to form an optionally substituted ring selected from 3- to 7-membered saturated or partially unsaturated monocyclic heterocyclyl having 1-2 heteroatoms selected from oxygen, nitrogen, or sulfur, or 5- to 6-membered heteroaryl having 1-4 heteroatoms selected from oxygen, nitrogen, or sulfur.

In some embodiments, the kit further comprises phosphate buffer at about pH 7.

In some embodiments, the compound of Formula I or the pharmaceutically acceptable salt thereof and chloramine-T are provided in a single container.

In some embodiments, the container comprising the compound of Formula I or the pharmaceutically acceptable salt thereof and chloramine-T further comprises acetic acid.

In some embodiments, the compound of Formula I or the pharmaceutically acceptable salt thereof and chloramine-T are provided in separate containers.

In some embodiments, the compound of Formula I or pharmaceutically acceptable salt thereof is provided in ethanol.

In some embodiments, the kit further comprises: i) ethanol; ii) water; iii) a reaction container; iv) a waste container; v) a product container; vi) a Sep-Pak; vii) one or more syringes; and/or viii) one or more stopcocks.

In some embodiments, the kit further comprises a radioiodine salt. In some embodiments, the radioiodine salt is sodium radioiodine.

In some embodiments, the radioiodine salt is a salt of I ¹²³ , I ¹²⁴ , or I ¹³¹ .

BRIEF DESCRIPTION OF DRAWINGS

Non-limiting embodiments of the present invention will be described by way of example with reference to the accompanying Figures, which are schematic and are not intended to be drawn to scale.

It is also to be understood that various Figures and exemplifications of this disclosure refer to "a compound of Formula.. Compounds 1-7, or particular chemical structures. However, the disclosure intends this for illustrative purposes only and it is to be in no way limiting. Any of the compounds disclosed herein or a pharmaceutically acceptable salt, cocrystal, tautomer, stereoisomer, solvate, hydrate, polymorph, isotopically enriched derivative, or prodrug thereof can be used as provided herein.

FIG. 1 is a schematic showing a non-limiting example of Compound 2 production using Pd ₂ (dba) ₃ . The following abbreviations are used in this figure: DCM: dichloromethane, MTBE: methyl tert-butyl ether, NET: not less than, NMT: not more than, PCT: process control test, MeOH: methanol, and Et3N: triethylamine

FIGs. 2A-2C are schematics showing a non-limiting example of synthesis of Compound 2 using Pd ₂ (dba) ₃ . FIGs. 2A-2C show steps 1-3, respectively.

FIG. 3 shows a non-limiting example of a device configured for synthesis of a compound of a radiolabeled Hsp90 inhibitor (e.g., a compound of Formula II, such as a compound of Formula III, or of Formula IV, or a pharmaceutically acceptable salt thereof, as defined herein). The device comprises the following components: R: reaction container (e.g., vial); W: waste container (e.g., vial); P: product container (e.g., vial); SP: Sep-Pak, SI, S2, and S3: Syringes; and SCI, SC2, SC3: stopcocks.

DETAIFED DESCRIPTION

This disclosure provides new and suprisingly improved methods for tin (Sn)-labeling and radiolabeling of compounds such as certain agents bind selectively to Hsp90 (i.e.., Hsp90 and/or Hsp90 isoforms and/or Hsp90 homologs such as but not limited to GRP94 and TRAP1) as it is complexed in an epichaperome, and are thus able to interfere with the structure and ultimately function of the epichaperome. Existing methods of Sn-labeling certain Hsp90 inhibitors, including those that make use of Pd(PPh3)4 as a catalyst, have resulted in reaction stalling and have required additional charges of the catalyst, rendering such methods inefficient and cumbersome. Methods described herein obviate certain limitations of existing methods of Sn-labeling of these compounds, by increasing the efficiency of the reaction and reducing reaction stalling. Aspects of the present disclosure provide methods of improving the yield of certain radiolabeled Hsp90 inhibitors. Radiolabeled Hsp90 inhibitors are useful in numerous clinical applications, including treatment of cancers, assessing the bioavailability of the inhibitor, disease diagnosis, and monitoring the efficacy of a treatment regimen. In some embodiments, the radiolabeled Hsp90 inhibitors disclosed herein may be used to determine the therapeutically effective amount of a non-radiolabeled Hsp90 inhibitor.

For the sake of brevity, the term Hsp90 will be used herein to collectively refer to Hsp90, its isoforms and its homologs such as but not limited to GRP94 and TRAP1. Thus, the Hsp90 inhibitors of this disclosure refer to a class of inhibitors that inhibit Hsp90 and/or Hsp90 isoforms and/or Hsp90 homologs including but not limited to GRP94 and TRAP1. In some embodiments, Hsp90 inhibitors interfere with the structure and ultimately function of an epichaperome.

As used herein, unless otherwise specified, the term "Hsp90 inhibitors" includes iodinated Hsp90 inhibitors, radiolabeled Hsp90 inhibitors and Sn-labeled Hsp90 inhibitors having a parent compound of Formula I, Formula II, or Formula V.

The Hsp90 inhibitor produced herein may interfere with the formation or stability of the epichaperome, thereby rendering target cells (such as cancer cells) more susceptible to cell death. The ability to target the epichaperome can also result in reduced general toxicity in subjects being treated. Accordingly, the inhibitors of this disclosure may also be referred to as epichaperome inhibitors.

The disclosure also provides methods of producing certain Hsp90 inhibitors comprising a radiolabel or producing precursor compounds (e.g., Sn-labeled Hsp90 inhibitor compounds) to be used in the production of a radiolabeled Hsp90 inhibitor.

Any of the compounds described herein, including those that are substrates and those that are products, may be a good manufacturing practices (GMP) grade compound.

Definitions

Compounds of this disclosure include those described generally above, and are further illustrated by the classes, subclasses, and species disclosed herein. As used herein, the following definitions shall apply unless otherwise indicated. For purposes of this disclosure, the chemical elements are identified in accordance with the Periodic Table of the Elements, CAS version, Handbook of Chemistry and Physics, 75 ^th Ed. Additionally, general principles of organic chemistry are described in "Organic Chemistry", Thomas Sorrell, University Science Books, Sausalito: 1999, and "March's Advanced Organic Chemistry", 5 ^th Ed., Ed.: Smith, M. B. and March, J., John Wiley & Sons, New York: 2001, the entire contents of which are hereby incorporated by reference.

The abbreviations used herein have their conventional meaning within the chemical and biological arts. The chemical structures and Formulae set forth herein are constructed according to the standard rules of chemical valency known in the chemical arts.

The term "about X," where X is a number or percentage, refers to a number or percentage that is between 99.5% and 100.5%, between 99% and 101%, between 98% and 102%, between 97% and 103%, between 96% and 104%, between 95% and 105%, between 92% and 108%, or between 90% and 110% of X, inclusive, of X.

The term "aliphatic" or "aliphatic group", as used herein, means a straight-chain (i.e., unbranched) or branched, substituted or unsubstituted hydrocarbon chain that is completely saturated or that contains one or more units of unsaturation, or a monocyclic hydrocarbon or bicyclic hydrocarbon that is completely saturated or that contains one or more units of unsaturation, but which is not aromatic (also referred to herein as "carbocycle," "cycloaliphatic" or "cycloalkyl"), that has a single point of attachment to the rest of the molecule. Unless otherwise specified, aliphatic groups contain 1-6 aliphatic carbon atoms. In some embodiments, aliphatic groups contain 1-5 aliphatic carbon atoms. In some embodiments, aliphatic groups contain 1-4 aliphatic carbon atoms. In some embodiments, aliphatic groups contain 1-3 aliphatic carbon atoms, and in yet other embodiments, aliphatic groups contain 1-2 aliphatic carbon atoms. In some embodiments, "cycloaliphatic" (or "carbocycle" or "cycloalkyl") refers to a monocyclic C3-C6 hydrocarbon that is completely saturated or that contains one or more units of unsaturation, but which is not aromatic, that has a single point of attachment to the rest of the molecule. Suitable aliphatic groups include, but are not limited to, linear or branched, substituted or unsubstituted alkyl, alkenyl, alkynyl groups and hybrids thereof such as (cycloalkyl)alkyl, (cycloalkenyl)alkyl or (cycloalkyl) alkenyl .

The term "heteroatom" means one or more of oxygen, sulfur, nitrogen, phosphorus, or silicon (including, any oxidized form of nitrogen, sulfur, phosphorus, or silicon; the quatemized form of any basic nitrogen or; a substitutable nitrogen of a heterocyclic ring, for example N (as in 3,4-dihydro-2H-pyrrolyl), NH (as in pyrrolidinyl) or NR (as in N- substituted pyrrolidinyl)).

The term "unsaturated," as used herein, means that a moiety has one or more units of unsaturation.

The term "alkylene" refers to a bivalent alkyl group. An "alkylene chain" is a polymethylene group, i.e., — (CH ₂ ) _{n —} , wherein n is a positive integer, preferably from 1 to 6, from 1 to 4, from 1 to 3, from 1 to 2, or from 2 to 3. A substituted alkylene chain is a polymethylene group in which one or more methylene hydrogen atoms are replaced with a substituent. Suitable substituents include those described below for a substituted aliphatic group.

The term "halogen" means F, Cl, Br, or I.

The term "aryl" refers to a radical of a monocyclic or polycyclic ( e.g ., bicyclic or tricyclic) 4n+2 aromatic ring system (e.g., having 6, 10, or 14 p electrons shared in a cyclic array) having 6-14 ring carbon atoms and zero heteroatoms provided in the aromatic ring system ("C _6-14 aryl"). In some embodiments, an aryl group has 6 ring carbon atoms ("C ₆ aryl"; e.g., phenyl). In some embodiments, an aryl group has 10 ring carbon atoms ("C ₁₀ aryl"; e.g., naphthyl such as 1-naphthyl and 2-naphthyl). In some embodiments, an aryl group has 14 ring carbon atoms ("C ₁₄ aryl"; e.g., anthracyl). Unless otherwise specified, each instance of an aryl group is independently unsubstituted (an "unsubstituted aryl") or substituted (a "substituted aryl") with one or more substituents. In certain embodiments, the aryl group is an unsubstituted C _6-14 aryl. In certain embodiments, the aryl group is a substituted C _6-14 aryl.

The term "heteroaryl" refers to a radical of a 5-14 membered monocyclic or polycyclic (e.g., bicyclic, tricyclic) 4n+2 aromatic ring system (e.g., having 6, 10, or 14 p electrons shared in a cyclic array) having ring carbon atoms and 1-4 ring heteroatoms provided in the aromatic ring system, wherein each heteroatom is independently selected from nitrogen, oxygen, and sulfur ("5-14 membered heteroaryl"). In heteroaryl groups that contain one or more nitrogen atoms, the point of attachment can be a carbon or nitrogen atom, as valency permits. Heteroaryl polycyclic ring systems can include one or more heteroatoms in one or both rings. "Heteroaryl" includes ring systems wherein the heteroaryl ring, as defined above, is fused with one or more carbocyclyl or heterocyclyl groups wherein the point of attachment is on the heteroaryl ring, and in such instances, the number of ring members continue to designate the number of ring members in the heteroaryl ring system. "Heteroaryl" also includes ring systems wherein the heteroaryl ring, as defined above, is fused with one or more aryl groups wherein the point of attachment is either on the aryl or heteroaryl ring, and in such instances, the number of ring members designates the number of ring members in the fused polycyclic (aryl/heteroaryl) ring system. Polycyclic heteroaryl groups wherein one ring does not contain a heteroatom (e.g., indolyl, quinolinyl, carbazolyl, and the like) the point of attachment can be on either ring, e.g., either the ring bearing a heteroatom (e.g., 2-indolyl) or the ring that does not contain a heteroatom (e.g., 5-indolyl). In certain embodiments, the heteroaryl is substituted or unsubstituted, 5- or 6-membered, monocyclic heteroaryl, wherein 1, 2, 3, or 4 atoms in the heteroaryl ring system are independently oxygen, nitrogen, or sulfur. In certain embodiments, the heteroaryl is substituted or unsubstituted, 9- or 10-membered, bicyclic heteroaryl, wherein 1, 2, 3, or 4 atoms in the heteroaryl ring system are independently oxygen, nitrogen, or sulfur.

In some embodiments, a heteroaryl group is a 5-10 membered aromatic ring system having ring carbon atoms and 1-4 ring heteroatoms provided in the aromatic ring system, wherein each heteroatom is independently selected from nitrogen, oxygen, and sulfur ("5-10 membered heteroaryl"). In some embodiments, a heteroaryl group is a 5-8 membered aromatic ring system having ring carbon atoms and 1-4 ring heteroatoms provided in the aromatic ring system, wherein each heteroatom is independently selected from nitrogen, oxygen, and sulfur ("5-8 membered heteroaryl"). In some embodiments, a heteroaryl group is a 5-6 membered aromatic ring system having ring carbon atoms and 1-4 ring heteroatoms provided in the aromatic ring system, wherein each heteroatom is independently selected from nitrogen, oxygen, and sulfur ("5-6 membered heteroaryl"). In some embodiments, the 5- 6 membered heteroaryl has 1-3 ring heteroatoms selected from nitrogen, oxygen, and sulfur. In some embodiments, the 5-6 membered heteroaryl has 1-2 ring heteroatoms selected from nitrogen, oxygen, and sulfur. In some embodiments, the 5-6 membered heteroaryl has 1 ring heteroatom selected from nitrogen, oxygen, and sulfur. Unless otherwise specified, each instance of a heteroaryl group is independently unsubstituted (an "unsubstituted heteroaryl") or substituted (a "substituted heteroaryl") with one or more substituents. In certain embodiments, the heteroaryl group is an unsubstituted 5-14 membered heteroaryl. In certain embodiments, the heteroaryl group is a substituted 5-14 membered heteroaryl.

Exemplary 5-membered heteroaryl groups containing 1 heteroatom include pyrrolyl, furanyl, and thiophenyl. Exemplary 5-membered heteroaryl groups containing 2 heteroatoms include imidazolyl, pyrazolyl, oxazolyl, isoxazolyl, thiazolyl, and isothiazolyl. Exemplary 5- membered heteroaryl groups containing 3 heteroatoms include triazolyl, oxadiazolyl, and thiadiazolyl. Exemplary 5-membered heteroaryl groups containing 4 hetero atoms include tetrazolyl. Exemplary 6-membered heteroaryl groups containing 1 heteroatom include pyridinyl. Exemplary 6-membered heteroaryl groups containing 2 heteroatoms include pyridazinyl, pyrimidinyl, and pyrazinyl. Exemplary 6-membered heteroaryl groups containing 3 or 4 heteroatoms include triazinyl and tetrazinyl, respectively. Exemplary 7- membered heteroaryl groups containing 1 heteroatom include azepinyl, oxepinyl, and thiepinyl. Exemplary 5,6-bicyclic heteroaryl groups include indolyl, isoindolyl, indazolyl, benzotriazolyl, benzothiophenyl, isobenzothiophenyl, benzofuranyl, benzoisofuranyl, benzimidazolyl, benzoxazolyl, benzisoxazolyl, benzoxadiazolyl, benzthiazolyl, benzisothiazolyl, benzthiadiazolyl, indolizinyl, and purinyl. Exemplary 6,6-bicyclic heteroaryl groups include naphthyridinyl, pteridinyl, quinolinyl, isoquinolinyl, cinnolinyl, quinoxalinyl, phthalazinyl, and quinazolinyl. Exemplary tricyclic heteroaryl groups include phenanthridinyl, dibenzofuranyl, carbazolyl, acridinyl, phenothiazinyl, phenoxazinyl, and phenazinyl.

As used herein, the terms "heterocycle," "heterocyclyl," "heterocyclic radical," and "heterocyclic ring" are used interchangeably and refer to a stable 5- to 7-membered monocyclic or 7-10-membered bicyclic heterocyclic moiety that is either saturated or partially unsaturated, and having, in addition to carbon atoms, one or more, preferably one to four, heteroatoms, as defined above. When used in reference to a ring atom of a heterocycle, the term "nitrogen" includes a substituted nitrogen. As an example, in a saturated or partially unsaturated ring having 0-3 heteroatoms selected from oxygen, sulfur or nitrogen, the nitrogen may be N (as in 3,4-dihydro-2H-pyrrolyl), NH (as in pyrrolidinyl), or ⁺ NR (as in N- substituted pyrrolidinyl).

A heterocyclic ring can be attached to its pendant group at any heteroatom or carbon atom that results in a stable structure and any of the ring atoms can be optionally substituted. Examples of such saturated or partially unsaturated heterocyclic radicals include, without limitation, tetrahydrofuranyl, tetrahydrothiophenyl pyrrolidinyl, piperidinyl, pyrrolinyl, tetrahydroquinolinyl, tetrahydroisoquinolinyl, decahydroquinolinyl, oxazolidinyl, piperazinyl, dioxanyl, dioxolanyl, diazepinyl, oxazepinyl, thiazepinyl, morpholinyl, and quinuclidinyl. The terms "heterocycle," "heterocyclyl," "heterocyclyl ring," "heterocyclic group," "heterocyclic moiety," and "heterocyclic radical," are used interchangeably herein, and also include groups in which a heterocyclyl ring is fused to one or more aryl, heteroaryl, or cycloaliphatic rings, such as indolinyl, 3H-indolyl, chromanyl, phenanthridinyl, or tetrahydroquinolinyl, where the radical or point of attachment is on the heterocyclyl ring. A heterocyclyl group may be mono- or bicyclic. The term "heterocyclylalkyl" refers to an alkyl group substituted by a heterocyclyl, wherein the alkyl and heterocyclyl portions independently are optionally substituted.

As used herein, the term "partially unsaturated" refers to a ring moiety that includes at least one double or triple bond. The term "partially unsaturated" is intended to encompass rings having multiple sites of unsaturation, but is not intended to include aryl or heteroaryl moieties, as herein defined.

As described herein, compounds of the disclosure may, when specified, contain "optionally substituted" moieties. In general, the term "substituted," whether preceded by the term "optionally" or not, means that one or more hydrogens of the designated moiety are replaced with a suitable substituent. Unless otherwise indicated, an "optionally substituted" group may have a suitable substituent at each substitutable position of the group, and when more than one position in any given structure may be substituted with more than one substituent selected from a specified group, the substituent may be either the same or different at every position. Combinations of substituents envisioned by this disclosure are preferably those that result in the formation of stable or chemically feasible compounds. The term "stable," as used herein, refers to compounds that are not substantially altered when subjected to conditions to allow for their production, detection, and, in certain embodiments, their recovery, purification, and use for one or more of the purposes disclosed herein.

Suitable monovalent substituents on a substitutable carbon atom of an "optionally substituted" group are independently halogen; — (CH ₂ ) _0-4 Rº; — (CH ₂ ) _0-4 OR°; — O(CH ₂ ) _0-4 Rº, — O— (CH ₂ ) _0-4 C(O)OR°; — (CH ₂ ) _0-4 CH(OR°) ₂ ; — (CH ₂ ) _0-4 SR°; — (CH ₂ ) _0-4 Ph, which may be substituted with R°; — (CH ₂ ) _0-4 O(CH ₂ ) _0-1 Ph which may be substituted with R°; — CH=CHPh, which may be substituted with R°; — (CH ₂ ) _0-4 O(CH ₂ ) _0-1 -pyridyl which may be substituted with R°; — N0 ₂ ; — CN; — N ₃ ; — (CH ₂ ) _0-4 N(R°) ₂ ; — (CH ₂ ) _0-4 N(R°)C(O)R°; — N(R°)C(S)R°;

— (CH ₂ ) _0-4 N(R°)C(O)NR° ₂ ; — N(R°)C(S)NR° ₂ ; — (CH ₂ ) _0-4 N(R°)C(O)OR°; — N(R°)N(R°)C(O)R°; — N(R°)N(R°)C(O)NR° ₂ ; — N(R°)N(R°)C(O)OR°; — (CH ₂ ) _0-4 C(O)R°; — C(S)R°; — (CH ₂ ) _O-4 C(O)OR°; — (CH ₂ ) _0-4 C(O)SR°; — (CH ₂ ) _0-4 C(O)OSiR° ₃ ; — (CH ₂ ) _{0- 4} OC(O)R°; — OC(O)(CH ₂ ) _0-4 SR— , SC(S)SR°; — (CH ₂ ) _0-4 SC(O)R; — (CH ₂ ) _0-4 C(O)NR° ₂ ; — C(S)NR° ₂ ; — C(S)SR°; — SC(S)SRO, — (CH ₂ ) _0-4 OC(O)NR° ₂ ; — C(O)N(OR)R°; — C(O)C(O)R°; C(O)CH ₂ C(O)R°; — C(NOR°)R°; — (CH ₂ ) _0-4 SSR°; — (CH ₂ ) _0-4 S(O) ₂ R°; — (CH ₂ ) _0-4 S (O) ₂ OR° ; — (CH ₂ ) _0-4 0S(O) ₂ R°; — S(O) ₂ NR° ₂ ; — (CH ₂ ) _0-4 S(O)R°; — N(R°)S(O) ₂ NR° ₂ ; — N(R°)S(O) ₂ R°; — N(OR°)R°; — C(NH)NR° ₂ ; — P(O) ₂ R°; — P(O)R° ₂ ; — 0P(O)R° 2; — OP(O)(OR°)2; SiR° 3; — (C _1-4 straight or branched alkylene)0 — N(R°) ₂ ; or — (C _1-4 straight or branched alkylene)C(O)O — N(R°) ₂ , wherein each R° may be substituted as defined below and is independently hydrogen, C _1-6 aliphatic, —CH ₂ Ph, — O(CH ₂ )o-iPh, — CH ₂ -(5-6 membered heteroaryl ring), or a 5-6-membered saturated, partially unsaturated, aryl ring, or heteroaryl ring having 1-4 heteroatoms independently selected from nitrogen, oxygen, or sulfur, or, notwithstanding the definition above, two independent occurrences of R°, taken together with their intervening atom(s), form a 3-12-membered saturated, partially unsaturated, aryl mono- or bicyclic ring, or heteroaryl mono- or bicyclic ring having 1-4 heteroatoms independently selected from nitrogen, oxygen, or sulfur, which may be substituted as defined below.

Suitable monovalent substituents on R° (or the ring formed by taking two independent occurrences of R° together with their intervening atoms), are independently halogen, — (CH ₂ )O-2R·, -(haloR ^· ), — (CH ₂ ) _0-2 OH, — (CH ₂ ) _0-2 OR, — (CH ₂ ) _0-2 CH(OR ^· ) ₂ ; — O(haloR _· ), — CN, — N ₃ , — (CH ₂ ) _0-2 C(O)R, — (CH ₂ ) _0-2 C(O)OH, — (CH ₂ ) _0-2 C(O)OR·, — (CH ₂ ) _0-2 SR·, — (CH ₂ ) _0-2 SH, — (CH ₂ ) _0-2 NH ₂ , — (CH ₂ ) _0-2 NHR ^· , — (CH ₂ ) _0-2 NR· ₂ , — N0 ₂ , — SiR ^· ₃ , —

OSiR ^· 3, — C(O)SR ^· , — (C _1-4 straight or branched alkylene)C(O)OR ^· , or — SSR ^· wherein each R* is unsubstituted or where preceded by "halo" is substituted only with one or more halogens, and is independently selected from C1-4 aliphatic, — CH ₂ Ph , — O(CH ₂ ) _0-1 Ph, or a 5- 6-membered saturated, partially unsaturated, aryl ring, or heteroaryl ring having 1-4 heteroatoms independently selected from nitrogen, oxygen, or sulfur. Suitable divalent substituents on a saturated carbon atom of R° include =0 and =S.

Suitable divalent substituents on a saturated carbon atom of an "optionally substituted" group include the following: =0, =S, =NNR*2, =NNHC(O)R*, =NNHC(O)OR*, =NNHS(O) ₂ R*, =NR*, =NOR*, — O(C(R* ₂ )) _2-3 O— , or — S(C(R* ₂ )) ₂ - ₃ S — , wherein each independent occurrence of R* is selected from hydrogen, Ci-6 aliphatic which may be substituted as defined below, or an unsubstituted 5-6-membered saturated, partially unsaturated, aryl ring, or heteroaryl ring having 1-4 heteroatoms independently selected from nitrogen, oxygen, or sulfur. Suitable divalent substituents that are bound to vicinal substitutable carbons of an "optionally substituted" group include: — O(CR* ₂ ) _2-3 O — , wherein each independent occurrence of R* is selected from hydrogen, C _1-6 aliphatic which may be substituted as defined below, or an unsubstituted 5-6-membered saturated, partially unsaturated, aryl ring, or heteroaryl ring having 1-4 heteroatoms independently selected from nitrogen, oxygen, or sulfur. Suitable substituents on the aliphatic group of R* include halogen, — R*, -(haloR*), —OH, —OR ^· , —O(haloR·), — CN, — C(O)OH, — C(O)OR ^· , — NH ₂ , — NHR ^· , —NR ^· ₂ , or — NO ₂ , wherein each R* is unsubstituted or where preceded by "halo" is substituted only with one or more halogens, and is independently C _1-4 aliphatic, — CH ₂ Ph, — O(CH ₂ ) _0-1 Ph, or a 5-6-membered saturated, partially unsaturated, aryl ring, or heteroaryl ring having 1-4 heteroatoms independently selected from nitrogen, oxygen, or sulfur.

Suitable substituents on a substitutable nitrogen of an "optionally substituted" group include — R ^† , — NR ^† ₂ , — C(O)R ^† , — C(O)OR ^† , — C(O)C(O)R ^† , — C(O)CH ₂ C(O)R ^† , — S(O) ₂ R ^† , — S(O) ₂ NR ^† ₂ , — C(S)NR ^† ₂ , — C(NH)NR ^† ₂ , or — N(R ^† )S(O) ₂ R ^† ; wherein each R ^† is independently hydrogen, C _1-6 aliphatic which may be substituted as defined below, unsubstituted — OPh, or an unsubstituted 5-6-membered saturated, partially unsaturated, aryl ring, or heteroaryl ring having 1-4 heteroatoms independently selected from nitrogen, oxygen, or sulfur, or, notwithstanding the definition above, two independent occurrences of R ^† , taken together with their intervening atom(s) form an unsubstituted 3-12-membered saturated, partially unsaturated, aryl mono- or bicyclic ring, or heteroaryl mono- or bicyclic ring having 1-4 heteroatoms independently selected from nitrogen, oxygen, or sulfur.

Suitable substituents on the aliphatic group of R ^† are independently halogen, — R*, - (haloR*), —OH, —OR*, —O(haloR*), — CN, — C(O)OH, — C(O)OR*, — NH ₂ , —NHR*, — NR* ₂ , or — N0 ₂ , wherein each R* is unsubstituted or where preceded by "halo" is substituted only with one or more halogens, and is independently Ci-4 aliphatic, — CH ₂ Ph, — O(CH ₂ ) _{0- 1} Ph, or a 5-6-membered saturated, partially unsaturated, aryl ring, or heteroaryl ring having 1- 4 heteroatoms independently selected from nitrogen, oxygen, or sulfur.

The term "pharmaceutically acceptable salt" refers to those salts which retain the biological effectiveness and properties of the "free" compounds provided herein. Any of the Hsp90 inhibitors or precursor compounds disclosed herein may be provided as pharmaceutically acceptable salts. A pharmaceutically acceptable salt can be obtained from the reaction of the free base of an active compound provided herein with an inorganic acid, for example, hydrochloric acid, hydrobromic acid, sulfuric acid, nitric acid, phosphoric acid, and the like, or an organic acid, for example, sulfonic acid, carboxylic acid, organic phosphoric acid, methanesulfonic acid, ethanesulfonic acid, p-toluenesulfonic acid, citric acid, fumaric acid, maleic acid, succinic acid, benzoic acid, salicylic acid, lactic acid, tartaric acid (e.g., (+) -tartaric acid or (-)-tartaric acid or mixtures thereof), and the like. Additional non-limiting examples of suitable acids include acetic acid, acetylsalicylic acid, adipic acid, alginic acid, ascorbic acid, aspartic acid, benzenesulfonic acid, bisulfic acid, boric acid, butyric acid, camphoric acid, camphorsulfonic acid, carbonic acid, citric acid, cyclopentanepropionic acid, digluconic acid, dodecylsulfic acid, formic acid, glyceric acid, glycerophosphoric acid, glycine, glucoheptanoic acid, gluconic acid, glutamic acid, glutaric acid, glycolic acid, hemisulfic acid, heptanoic acid, hexanoic acid, hippuric acid, hydroiodic acid, hydroxyethanesulfonic acid, malic acid, malonic acid, mandelic acid, mucic acid, naphthylanesulfonic acid, naphthylic acid, nicotinic acid, nitrous acid, oxalic acid, pelargonic, propionic acid, saccharin, sorbic acid, thiocyanic acid, thioglycolic acid, thiosulfuric acid, tosylic acid, undecylenic acid, and naturally and synthetically derived amino acids.

Certain active compounds provided herein have acidic substituents and can exist as pharmaceutically acceptable salts with pharmaceutically acceptable bases. The present disclosure includes such salts. Examples of such salts include metal counterion salts, such as sodium, potassium, lithium, magnesium, calcium, iron, copper, zinc, silver, or aluminum salts, and organic amine salts, such as methylamine, dimethylamine, trimethylamine, diethylamine, triethylamine, n-propylamine, 2 -propylamine, or dimethylisopropylamine salts, and the like.

The term "pharmaceutically acceptable salt" includes mono-salts and compounds in which a plurality of salts is present, e.g. , di-salts and/or tri-salts. Pharmaceutically acceptable salts can be prepared by methods known to those in the art.

In certain embodiments, the neutral forms of the compounds are regenerated by contacting the salt with a base or acid and isolating the parent compound in the conventional manner. In some embodiments, the parent form of the compound differs from the various salt forms in certain physical properties, such as solubility in polar solvents.

Unless otherwise stated, structures depicted herein are also meant to include all isomeric (e.g., enantiomeric, diastereomeric, and geometric (or conformational)) forms of the structure; for example, the R and S configurations for each asymmetric center, Z and E double bond isomers, and Z and E conformational isomers. Therefore, single stereochemical isomers as well as enantiomeric, diastereomeric, and geometric (or conformational) mixtures of the present compounds are within the scope of the disclosure. Unless otherwise stated, all tautomeric forms of the compounds of the disclosure are within the scope of the disclosure. Additionally, unless otherwise stated, structures depicted herein are also meant to include compounds that differ only in the presence of one or more isotopically enriched atoms. For example, compounds having the present structures including the replacement of hydrogen by deuterium or tritium, or the replacement of a carbon by a ¹³ C- or ¹⁴ C-enriched carbon are within the scope of this disclosure. Such compounds are useful, for example, as analytical tools, as probes in biological assays, or as therapeutic agents in accordance with the present disclosure.

The term "oxo," as used herein, means an oxygen that is double bonded to a carbon atom, thereby forming a carbonyl.

One of ordinary skill in the art will appreciate that the synthetic methods, as described herein, utilize a variety of protecting groups. By the term "protecting group," as used herein, it is meant that a particular functional moiety, e.g., O, S, or N, is masked or blocked, permitting, if desired, a reaction to be carried out selectively at another reactive site in a multifunctional compound. Suitable protecting groups are well known in the art and include those described in detail in Protecting Groups in Organic Synthesis , T. W. Greene and P. G. M. Wuts, 3 ^rd edition, John Wiley & Sons, 1999, the entirety of which is incorporated herein by reference. In certain embodiments, a protecting group reacts selectively in good yield to give a protected substrate that is stable to the projected reactions; the protecting group is preferably selectively removable by readily available, preferably non-toxic reagents that do not attack the other functional groups; the protecting group forms a separable derivative (more preferably without the generation of new stereogenic centers); and the protecting group will preferably have a minimum of additional functionality to avoid further sites of reaction. As detailed herein, oxygen, sulfur, nitrogen, and carbon protecting groups may be utilized. Amino-protecting groups include methyl carbamate, 9-fluorenylmethyl carbamate (Fmoc), 9- (2,7-dibromo)fluoroenylmethyl carbamate, 4-methoxyphenacyl carbamate (Phenoc), 2,2,2- trichloroethyl carbamate (Troc), 2-trimethylsilylethyl carbamate (Teoc), 1 -methyl- 1 -(4- biphenylyl)ethyl carbamate (Bpoc), 2-(2'- and 4'-pyridyl)ethyl carbamate (Pyoc), 2-(N,N- dicyclohexylcarboxamido)ethyl carbamate, t-butyl carbamate (BOC), allyl carbamate (Alloc), 4-nitrocinnamyl carbamate (Noc), N-hydroxypiperidinyl carbamate, alkyldithio carbamate, benzyl carbamate (Cbz), p-nitobenzyl carbamate, p-chlorobenzyl carbamate, diphenylmethyl carbamate, 2-methylsulfonylethyl carbamate, 2-(p-toluenesulfonyl)ethyl carbamate, 2,4- dimethylthiophenyl carbamate (Bmpc), 2-triphenylphosphonioisopropyl carbamate (Ppoc), m-chloro-p-acyloxybenzyl carbamate, p-(dihydroxyboryl)benzyl carbamate, m-nitrophenyl carbamate, 3,5-dimethoxybenzyl carbamate, o-nitrobenzyl carbamate, phenyl(o- nitrophenyl)methyl carbamate, N'-p-toluenesulfonylaminocarbonyl derivative, N'- phenylaminothiocarbonyl derivative, t-amyl carbamate, p-cyanobenzyl carbamate, cyclohexyl carbamate, cyclopentyl carbamate, p-decyloxybenzyl carbamate, 2,2- dimethoxycarbonylvinyl carbamate, 2-furanylmethyl carbamate, isoborynl carbamate, isobutyl carbamate, 1 -methyl- 1-phenylethyl carbamate, 1 -methyl- l-(4-pyridyl)ethyl carbamate, phenyl carbamate, formamide, acetamide, chloroacetamide, trichloroacetamide, trifluoroacetamide, phenylacetamide, 3-phenylpropanamide, picolinamide, N- benzoylphenylalanyl derivative, benzamide, p-phenylbenzamide, o-nitrophenoxyacetamide, acetoacetamide, 4-chlorobutanamide, 3 -methyl-3 -nitrobutanamide, o-nitrocinnamide, N- acetylmethionine derivative, o-nitrobenzamide, o-(benzoyloxymethyl)benzamide, 4,5- diphenyl-3-oxazolin-2-one, N-phthalimide, N-2,5-dimethylpyrrole, N-methylamine, N- allylamine, N-[2-(trimethylsilyl)ethoxy]methylamine (SEM), N-3-acetoxypropylamine, N- benzylamine, N-triphenylmethylamine (Tr), N-2-picolylamino N'-oxide, N-1,1- dimethylthiomethyleneamine, N-benzylideneamine, N-p-methoxybenzylideneamine, N — (N',N'-dimethylaminomethylene)amine, N,N'-isopropylidenediamine, N-p- nitrobenzylideneamine, N-(5-chloro-2-hydroxyphenyl)phenylmethyleneamine, N- cyclohexylideneamine, N-(5,5-dimethyl-3-oxo-l-cyclohexenyl)amine, N-borane derivative, N-diphenylborinic acid derivative, N-nitroamine, N-nitrosoamine, amine N-oxide, diphenylphosphinamide (Dpp), dimethylthiophosphinamide (Mpt), dialkyl phosphoramidates, dibenzyl phosphoramidate, diphenyl phosphoramidate, benzenesulfenamide, o- nitrobenzenesulfenamide (Nps), 2,4-dinitrobenzenesulfenamide, pentachlorobenzenesulfenamide, 2-nitro-4-methoxybenzenesulfenamide, triphenylmethylsulfenamide, p-toluenesulfonamide (Ts), benzenesulfonamide, 2,3,6,- trimethyl-4-methoxybenzenesulfonamide (Mtr), 2,4,6-trimethoxybenzenesulfonamide (Mtb), 2,6-dimethyl-4-methoxybenzenesulfonamide (Pme), 2,3,5,6-tetramethyl-4- methoxybenzenesulfonamide (Mte), 4-methoxybenzenesulfonamide (Mbs), 2,4,6- trimethylbenzenesulfonamide (Mts), methanesulfonamide (Ms), b- trimethylsilylethanesulfonamide (SES), benzylsulfonamide, trifluoromethylsulfonamide, and phenacylsulfonamide. Exemplary protecting groups are detailed herein, however, it will be appreciated that the present disclosure is not intended to be limited to these protecting groups; rather, a variety of additional equivalent protecting groups can be readily identified using the above criteria and utilized in the method of the present disclosure. Additionally, a variety of protecting groups are described by Greene and Wuts ( Protecting Groups in Organic Synthesis, T. W. Greene and P. G. M. Wuts, 3rd edition, John Wiley & Sons, 1999). In some embodiments, a compound described herein does not contain a protecting group. In some embodiments, a compound described herein does not contain a Boc protecting group.

The term "radiolabel", as used herein, refers to a moiety comprising a radioactive isotope of at least one element. Exemplary suitable radiolabels include but are not limited to those described herein. In some embodiments, a radiolabel is one used in positron emission tomography (PET). In some embodiments, a radiolabel is one used in single-photon emission computed tomography (SPECT). In some embodiments, the radiolabel is radioiodine. In some embodiments, the radioiodine is selected from I ¹²³ , I ¹²⁴ , or I ¹³¹ .

The symbol except when used as a bond to depict unknown or mixed stereochemistry, denotes the point of attachment of a chemical moiety to the remainder of a molecule or chemical Formula.

The term "good manufacturing practices (GMP) grade compound" refers to a compound produced according to practices that conform to the guidelines recommended by agencies that control the authorization and licensing of the manufacture of the compound for the intended use. As a non-limiting example, a good manufacturing practices (GMP) grade compound is suitable for use based on U.S. Food and Drug Administration guidelines.

Production of Sn-labeled Hsp90 inhibitors

Aspects of the present disclosure provide methods of producing Sn-labeled Hsp90 inhibitors. In some embodiments, the method comprises one or more steps depicted in FIGs. 2A-2C. In some embodiments, the method comprises all of the steps depicted in FIGs. 2A- 2C. As a non-limiting example, Step 1 shown in FIG. 2A allows for a one-step synthesis of a Sn-labeled Hsp90 inhibitor. Step 2 shown in FIG. 2B allows for purification of the synthesized Sn-labeled Hsp90 inhibitor. Purification of an Sn-labeled Hsp90 inhibitor may comprise silica gel chromatography and/or use of solvents for separation of target compound from impurities ( e.g ., dichloromethane and/or toluene). Purification of an Sn-labeled Hsp90 inhibitor may further comprise crystallization (e.g., with dichloromethane and methyl tert- butyl ether (MTBE)). Step 3 shown in FIG. 2B allows for further purification of a synthesized Sn-labeled Hsp90 inhibitor. For example, a synthesized Sn-labeled Hsp90 inhibitor purified via crystallization (e.g., with ethanol and/or heptane). As one of ordinary skill in the art would appreciate one or more purification steps shown in FIGs. 2A-2C may be omitted.

In certain embodiments the present disclosure provides a method of producing a compound of Formula I: comprising reacting in a reaction mixture: a compound of Formula V: (Formula V) with hexamethylditin (Sn ₂ MOe ₆ ) and tris(dibenzylideneacetone)dipalladium(0) (Pd ₂ (dba) ₃ ) in a solution, wherein each of R ¹ , R ² , R ³ , R ⁴ , L, X, Y ¹ , Y ² , Z ¹ , Z ² , and Z ³ is as defined above and described in classes and subclasses herein.

Any substrates and/or products may be good manufacturing practices (GMP) grade compounds.

In some embodiments, X is — CH ₂ — . In some embodiments, X is — S — . In other embodiments, X is — O — .

In certain embodiments, Y ¹ is — CR ^3a — . In certain embodiments, Y ¹ is — N — .

In certain embodiments, Y ² is — CR ^3a — . In certain embodiments, Y ² is — N — .

In some embodiments, R ^3a is hydrogen.

In certain embodiments, Z ¹ is — CH — . In certain embodiments, Z ¹ is — N — . In certain embodiments, Z ² is — CH — . In certain embodiments, Z ² is — N — .

In certain embodiments, Z ³ is — CH — . In certain embodiments, Z ³ is — N — .

In some embodiments, R ¹ is hydrogen. In some embodiments, R ¹ is halogen. In some embodiments, R ¹ is fluro.

In some embodiments, -L-R ² comprises a methylene that is replaced with — NH — to form a secondary amine.

In some embodiments, L is a straight or branched, C _2-14 aliphatic group wherein one or more carbons are independently replaced by — NR — , wherein R is not a -Boc protecting group in L. In some embodiments, -L-R ² does not contain a Boc-protected secondary amine. In some embodiments, -L-R ² does not contain a secondary amine that is protected with an acid-labile protecting group. In some embodiments, -L-R ² does not contain a protected secondary amine.

In some embodiments, L is a straight or branched, optionally substituted C _{2- 14} aliphatic group wherein one, two, or three carbons are optionally and independently replaced by -Cy-, —NR—, — N(R)C(O)— , — C(O)N(R)— , — C(O)N(O)— , — N(R)SO _2— , — SO ₂ N(R)— , — O— , — C(O)— , — OC(O)— , — C(O)O— , — S— , —SO—, or — SO _2— ,

In some embodiments, L is a straight or branched, C _2-14 aliphatic group wherein a methylene of the aliphatic group is replaced with — NH — to form a secondary amine. In some embodiments, L is a straight or branched, C _2-12 aliphatic group wherein a methylene of the aliphatic group is replaced with — NH — to form a secondary amine. In some embodiments, L is a straight or branched, C _2-10 aliphatic group wherein a methylene of the aliphatic group is replaced with — NH — to form a secondary amine. In some embodiments,

L is a straight or branched, C _2-8 aliphatic group wherein a methylene of the aliphatic group is replaced with — NH — to form a secondary amine. In some embodiments, L is a straight or branched, C _2-6 aliphatic group wherein a methylene of the aliphatic group is replaced with — NH — to form a secondary amine. In some embodiments, L is a straight or branched, C _2- 4 aliphatic group wherein a methylene of the aliphatic group is replaced with — NH — to form a secondary amine. In some embodiments, L is a straight or branched, C _6-14 aliphatic group wherein a methylene of the aliphatic group is replaced with — NH — to form a secondary amine. In some embodiments, L is a straight or branched, C _6-12 aliphatic group wherein a methylene of the aliphatic group is replaced with — NH — to form a secondary amine.

In some embodiments, L is a straight or branched, C _2-14 aliphatic group wherein one or more carbons are optionally and independently replaced by -Cy- or — C(O) — . In some embodiments, L is a straight or branched, C _2-8 aliphatic group wherein one or more carbons are optionally and independently replaced by -Cy- or — C(O) — . In certain embodiments, L is a straight or branched, C _2-8 aliphatic group wherein one carbon of L is replaced by -Cy- and wherein -Cy- is a 6-membered saturated ring having one heteroatom selected from nitrogen.

In some embodiments, -Cy- is an optionally substituted 3-8 membered bivalent, saturated, partially unsaturated, aryl ring, or heteroaryl ring having 1-4 heteroatoms independently selected from nitrogen, oxygen, or sulfur. In some embodiments, -Cy- is an optionally substituted 3-8 membered bivalent, saturated ring having 1-2 heteroatoms independently selected from nitrogen, oxygen, or sulfur. In some embodiments, -Cy- is an optionally substituted 5-6 membered bivalent, saturated ring having 1-2 heteroatoms independently selected from nitrogen, oxygen, or sulfur. In some embodiments, -Cy- is bivalent piperidinyl.

In some embodiments, R ² is hydrogen. In other embodiments, R ² is optionally substituted C _1-6 aliphatic. In some embodiments, R ² is optionally substituted C 1-4 aliphatic. In some embodiments, R ² is C1-4 alkyl. In some embodiments, R ² is 3- to 7-membered saturated or partially unsaturated monocyclic heterocyclyl having 1-2 heteroatoms selected from oxygen, nitrogen, or sulfur. In some embodiments, R ² is 5- to 6-membered saturated or partially unsaturated monocyclic heterocyclyl having 1-2 heteroatoms selected from oxygen, nitrogen, or sulfur. In some embodiments, R ² is piperidinyl. In some embodiments, R ² is aziridinyl.

In some embodiments, R ² is 3- to 7-membered saturated or partially unsaturated monocyclic carbocyclyl. In some embodiments, R ² is cyclopropyl.

In some embodiments, -L-R ² forms a primary amino-alkyl group. In some embodiments, -L-R ² forms a secondary alkyl-amino-alkyl group. In some embodiments, -L-R ² is selected from the following:

In some embodiments, -L-R ² is selected from the following:

In some embodiments, each R ³ is independently halogen, — CN, — OR, — SR, — NCR) _! , or optionally substituted C _1-6 aliphatic. In some embodiments, each R ³ is — OR. In some embodiments, one or both of Y ¹ and Y ² is =CR ^3a — , as valency permits and there are two occurrences of R ³ . In some embodiments, one or both of Y ¹ and Y ² is =CR ^3a — , as valency permits and there is one occurrence of R ³ . In some embodiments, both Y ¹ and Y ² are =N — , as valency permits and there are two occurrences of R ³ . In some embodiments, both Y ¹ and Y ² are =N — , as valency permits and there is one occurrence of R ³ .

In some embodiments, a compound of Formula V comprises Compound 6:

In some embodiments, a compound of Formula V comprises Compound 7:

In some embodiments, there is at least one substituent on the ring bearing a trialkyltin group, and one of such substituents is located at the 5' position, wherein the ring numbering is as depicted below:

In some embodiments, there are two substituents on the ring bearing the trialkyltin group, located at the 4' and 5' positions. In some embodiments, these two substituents are taken together with their intervening atoms to form Ring A. In certain embodiments wherein R ³ is — OR, R is C _1-6 aliphatic. In certain embodiments wherein R ³ is — OR, R is methyl.

In some embodiments, two R ³ groups are taken together with their intervening atoms to form Ring A, wherein Ring A is an optionally substituted 5- to 6-membered partially unsaturated monocyclic heterocyclyl having 1-2 heteroatoms selected from oxygen, nitrogen, or sulfur, an optionally substituted 5- to 6-membered heteroaryl having 1-4 heteroatoms selected from oxygen, nitrogen, or sulfur, or 6-membered aryl. In certain embodiments, Ring A is a 5-membered partially unsaturated monocyclic heterocyclyl having 2 heteroatoms selected from oxygen. In certain embodiments, Ring A is a 5-membered partially unsaturated monocyclic heterocyclyl having 1 heteroatom selected from oxygen. In certain embodiments, Ring A is a 6-membered partially unsaturated monocyclic heterocyclyl having 2 heteroatoms selected from oxygen. In some embodiments, Ring A is phenyl.

In some embodiments, two R ³ groups are taken together with their intervening atoms to form Ring A, wherein Ring A is an optionally substituted 3- to 7-membered partially unsaturated carbocyclyl. In some embodiments, Ring A is an optionally substituted 5- to 6- membered partially unsaturated carbocyclyl.

In some embodiments, R ⁴ is methyl. In some embodiments, R ⁴ is ethyl. In some embodiments, R ⁴ is butyl.

In certain embodiments, a compound of the present disclosure is other than: wherein each of Ring A, R ¹ , R ² , R ⁴ , L, Y ¹ , Y ² , Z ¹ , Z ² , Z ³ , and X is as defined above and described in classes and subclasses herein, both singly and in combination.

In some embodiments, a compound provided herein is of Formula I-a:

I-a wherein each of R ¹ , R ² , L, and X is as defined above and described in classes and subclasses herein, both singly and in combination. In certain embodiments, a compound is a compound of Formula I-a and:

X is — CH ₂ — or — S— ;

R ¹ is hydrogen or halogen; and

L is a straight or branched, C _2-14 aliphatic group wherein one or more carbons are independently replaced by — NR — , wherein R is not a -Boc protecting group in L.

In some embodiments, a compound provided herein is a compound of Formula I-b, I- c, I-d, I-e, I-f, I-g, I-h, or I-j:

wherein each of R ¹ , R ² , R ⁴ , L, X, Y ¹ , Y ² , Z ¹ , Z ² , Z ³ , and R is as defined above and described in classes and subclasses herein, both singly and in combination.

In some embodiments, a compound provided herein is a compound of Formula I-i: I-i wherein each of R ¹ , R ² , R ⁴ , L, and X is as defined above and described in classes and subclasses herein, both singly and in combination. In certain embodiments, a compound of Formula I is selected from those depicted in

Table 1.

Table 1. Non-limiting exemplary compounds of Formula I

In some embodiments, the method comprises reacting a compound of Formula V: (Formula V) with hexamethylditin (Sn ₂ Me ₆ ) and tris(dibenzylideneacetone)dipalladium(0) (Pd ₂ (dba) ₃ ) in a solution between about 60 °C to about 80 °C ( e.g between about 60°C to about 65°C, between about 65°C to about 70°C, between about 70°C to about 75°C, or between about 75°C to about 80°C, between about 65°C to about 75°C, between about 60°C to about 70°C, or between about 70°C to about 80°C). In some embodiments, the temperature is about 65°C and about 75°C, or about 70°C.

In some embodiments, use of tris(dibenzylideneacetone)dipalladium(0) (Pd ₂ (dba) ₃ ) as a catalyst reduces reaction stalling by at least 1%, 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, or 100% as compared to a control. In some embodiments, use of tris(dibenzylideneacetone)dipalladium(0) (Pd ₂ (dba) ₃ ) as a catalyst reduces reaction stalling by at most 1%, 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, or 100% as compared to a control. In some embodiments, use of tris(dibenzylideneacetone)dipalladium(0) (Pd ₂ (dba) ₃ ) as a catalyst reduces reaction stalling by about 1%, about 5%, about 10%, about 15%, about 20%, about 25%, about 30%, about 35%, about 40%, about 45%, about 50%, about 55%, about 60%, about 65%, about 70%, about 75%, about 80%, about 85%, about 90%, about 95%, or about 100% as compared to a control. In some embodiments, use of tris(dibenzylideneacetone)dipalladium(0) (Pd ₂ (dba) ₃ ) as a catalyst reduces reaction stalling about 1% to about 10%, about 1% to about 50%, about 50% to about 100%, about 10% to about 20%, about 20% to about 30%, 30% to about 40%, 40% to about 50%, 50% to about 60%, 70% to about 80%, 80% to about 90%, 90% to about 100% as compared to a control. In some embodiments, a control is performed using the same reaction but with a different catalyst, e.g., Pd(PPh ₃ ) ₄ in place of Pd ₂ (dba) ₃ . In some embodiments, reaction stalling is measured by the time it takes to produce a certain amount (mass) of product (i.e., the product yield), and the reduction in reaction stalling may be measured by comparison with the reaction time when another catalyst is used, including for example Pd(PPh3)4. In some embodiments, reaction stalling time is measured from when the substrates are initially combined. In some embodiments, the amount of substrate and the amount of product are measured for a reaction, and reaction stalling occurs when the conversion of the substrate to the product does not change for a particular amount of time (e.g., for about 1 minute, 2 minutes, 3 minutes, 4 minutes, 5 minutes, 6 minutes, 7 minutes, 8 minutes, 9 minutes, 10, minutes, 15 minutes, 20 minutes, 25 minutes, 30 minutes, 50 minutes, or an hour). In some embodiments, additional catalyst is added to the reaction following the stalling of a reaction.

In some embodiments, a reaction is stopped when the product (e.g., the Sn-labeled form of the Hsp90 inhibitor) represents greater than 70% of the combined amount of the product and substrate (e.g., the Sn-labeled form and the iodine-labeled form of the Hsp90 inhibitor) present in the reaction mixture ( e.g ., between 70% to 80%, between 80% to 90%, or between 90% to 100% (e.g., about 70%, about 75%, about 80%, about 85%, about 90%, or about 95%).

In some embodiments, use of tris(dibenzylideneacetone)dipalladium(0) (Pd ₂ (dba) ₃ ) as a catalyst improves the product yield. Improved product yield may be measured by the increased amount (mass) of product produced when Pd ₂ (dba) ₃ is used as a catalyst compared to when another catalyst (e.g., Pd(PPh3)4) is used. The yield may be improved by at least 1%, 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, 100%, 200%, 300%, 400%, 500%, 600%, 700%, 800%, 900%, or 1000% when using tris(dibenzylideneacetone)dipalladium(0) (Pd ₂ (dba) ₃ ) as compared to a control that uses another catalyst. The yield may be improved by at most 1%, 5%, 10%, 15%,

20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, 100%, 200%, 300%, 400%, 500%, 600%, 700%, 800%, 900%, or 1000% when using tris(dibenzylideneacetone)dipalladium(0) (Pd ₂ (dba) ₃ ) as compared to a control that uses another catalyst. The yield may be improved by 1% to 50%, 50 to 100%, 100% to 200%, 200% to 300%, 300% to 400%, 400% to 500%, 500% to 600%, 600% to 700%, 700% to 800%, 800% to 900%, 900% to 1000% when using tris(dibenzylideneacetone)dipalladium(0) (Pd ₂ (dba) ₃ ) as compared to a control that uses another catalyst.

In some embodiments, the control uses Pd(PPh3)4 as the catalyst.

In some embodiments, the method further comprises purifying an Sn-labeled Hsp90 inhibitor by mixing the Sn-labeled Hsp90 inhibitor with dichloromethane (DCM) and stirring the mixture to form a substantially clear solution. A substantially clear solution may be determined by eye. In some embodiments, the method comprises adding water to the substantially clear solution, stirring the solution for at least 5 minutes (e.g., at least 6 minutes, at least 7 minutes, at least 8 minutes, at least 10 minutes, at least 15 minutes, at least 20 minutes, at least 25 minutes, at least 30 minutes, at least 35 minutes, at least 40 minutes, at least 45 minutes, at least 50 minutes, or at least 60 minutes, but typically no longer than 90 minutes (e.g., about 5 to about 90 minutes, about 6 to about 90 minutes, about 7 to about 90 minutes, about 8 to about 90 minutes, about 9 to about 90 minutes, about 10 to about 90 minutes, about 15 to about 90 minutes, about 20 to about 90 minutes, about 25 to about 90 minutes, about 30 to about 90 minutes, about 35 to about 90 minutes, about 40 to about 90 minutes, about 45 to about 90 minutes, about 50 to about 90 minutes, about 55 to about 90 minutes, about 60 to about 90 minutes), and allowing or causing the solution to separate into an organic layer and an aqueous layer. In some embodiments, the water is purified water. In some embodiments, the method comprises performing these steps one or more times. For example, a cycle comprising the steps of adding water to the solution, stirring the solution for at least 5 minutes, and allowing or causing the solution to separate into an organic layer and an aqueous layer, may be performed at least 1 time, at least 2 times, at least 3 times, at least 4 times, at least 5 times, at least 6 times, at least 7 times, at least 8 times, at least 9 times, or at least 10 times, but typically no more than 12 times. In some embodiments, the water is purified water. In some embodiments, the solution is stirred for the same length of time in all of the cycles performed. In some embodiments, the solution is stirred for different lengths of time when the cycle is repeated.

In some embodiments, a method comprises filtering the organic layer, washing the reaction vessel with DCM, and concentrating the filtrate and the wash. In some embodiments, the concentrating occurs at no more than 50 °C (e.g., no more than 45 °C, 40 °C, 35 °C, 30 °C, 25 °C, 20 °C, 15 °C, or 10 °C) to distill the product. In some embodiments, the concentrating occurs at no less than 25 °C (e.g., no less than 45 °C, 40 °C, 35 °C, 30 °C, or 25 °C)) to distill the product. In some embodiments, the product is dried under vacuum at no more than 70 °C (e.g., no more than 65 °C, 60 °C, 55 °C, 50 °C, 45 °C, 40 °C, 35 °C, 30 °C, 25 °C, 20 °C, 15 °C, or 10 °C). In some embodiments, the product is dried under vacuum at no less than 10 °C (e.g., no less than 65 °C, 60 °C, 55 °C, 50 °C, 45 °C, 40 °C, 35 °C, 30 °C, 25 °C, 20 °C, or 15 °C).

In some embodiments, a method comprises adding ethanol (EtOH)-Heptane to the product, which may be useful to precipitate the product.

In some embodiments, the product comprises a compound of Formula I.

Production of Radiolabeled Hsp90 inhibitors

Further aspects of the disclosure provide methods of producing radiolabeled Hsp90 inhibitors. The methods of producing a radiolabeled Hsp90 inhibitor disclosed herein comprise producing a compound of Formula II: (Formula II), reacting, as substrates, a radioiodine and a compound of Formula I: (Formula I), wherein:

W is radioiodine; X is — CH ₂ — , — O— , or — S— ;

Y ¹ and Y ² are independently =CR ^3a — or =N — , as valency permits;

Z ¹ , Z ² , and Z ³ are independently — CH= or — N=, as valency permits;

R ¹ is hydrogen or halogen;

L is a straight or branched, C2-14 aliphatic group wherein one or more carbons are optionally and independently replaced by -Cy-, — N(R)C(O) — , — C(O)N(R) — , —

C(O)N(O) — , — N(R)SO _2— , — SO ₂ N(R)— , — O— , — C(O)— , — OC(O)— , — C(O)O— , — S — , — SO — , or — SO _{2 —} , or wherein one or more carbons are independently replaced by — NR — , wherein R is other than a -Boc protecting group; each -Cy- is independently an optionally substituted 3-8 membered bivalent, saturated, partially unsaturated, aryl ring, or heteroaryl ring having 1-4 heteroatoms independently selected from nitrogen, oxygen, or sulfur, or an optionally substituted 8-10 membered bivalent saturated, partially unsaturated, , aryl bicyclic ring, or heteroaryl bicyclic ring having 1-5 heteroatoms independently selected from nitrogen, oxygen, or sulfur;

R ² is hydrogen or an optionally substituted group selected from the group consisting of C _1-6 aliphatic, phenyl, 3- to 7-membered saturated or partially unsaturated monocyclic carbocyclyl, 3- to 7-membered saturated or partially unsaturated monocyclic heterocyclyl having 1-2 heteroatoms selected from oxygen, nitrogen, or sulfur, 5- to 6-membered heteroaryl having 1-4 heteroatoms selected from oxygen, nitrogen, or sulfur, 7- to 10- membered saturated or partially unsaturated bicyclic carbocyclyl, 7- to 10-membered saturated or partially unsaturated bicyclic heterocyclyl having 1-4 heteroatoms selected from oxygen, nitrogen, or sulfur, 7- to 10-membered bicyclic heteroaryl having 1-4 heteroatoms selected from oxygen, nitrogen, or sulfur, or 8- to 10-membered bicyclic aryl; each R ³ is independently halogen, — NO ₂ , — CN, — OR, — SR, — N(R) ₂ , — C(O)R,

— CO ₂ R, — C(O)C(O)R, — C(O)CH ₂ C(O)R, — S(O)R, — S(O) ₂ R, — C(O)N(R) ₂ , — SO ₂ N(R) ₂ , —OC(O)R, — N(R)C(O)R, — N(R)N(R) ₂ , or optionally substituted C _1-6 aliphatic or pyrrolyl; or two R ³ groups are taken together with their intervening atoms to form Ring A, wherein Ring A is an optionally substituted 3- to 7-membered partially unsaturated carbocyclyl, optionally substituted phenyl, an optionally substituted 5- to 6-membered partially unsaturated monocyclic heterocyclyl having 1-2 heteroatoms selected from oxygen, nitrogen, or sulfur; or an optionally substituted 5- to 6-membered heteroaryl having 1-4 heteroatoms selected from oxygen, nitrogen, or sulfur, or 6-membered aryl;

R ^3a is R ³ or hydrogen;

R ⁴ is C _1-4 alkyl; each R is independently hydrogen or an optionally substituted group selected from C _{1- 6} aliphatic, phenyl, 3- to 7-membered saturated or partially unsaturated carbocyclyl, 3- to 7- membered saturated or partially unsaturated monocyclic heterocyclyl having 1-2 heteroatoms selected from oxygen, nitrogen, or sulfur, or 5- to 6-membered heteroaryl having 1-4 heteroatoms selected from oxygen, nitrogen, or sulfur, or: two R groups on the same nitrogen are taken together with their intervening atoms to form an optionally substituted ring selected from 3- to 7-membered saturated or partially unsaturated monocyclic heterocyclyl having 1-2 heteroatoms selected from oxygen, nitrogen, or sulfur, or 5- to 6-membered heteroaryl having 1-4 heteroatoms selected from oxygen, nitrogen, or sulfur.

In some embodiments, the compound of Formula II comprises: (Formula III); or

(Formula IV), wherein W is a radioiodine.

In some embodiments, the compound of Formula I comprises:

In some embodiments, the compound of Formula I is provided as a free base. In some embodiments, the compound of Formula I is provided as a hydrogen iodide salt (HI). In some embodiments, the compound of Formula I is reacted with a radioiodine sodium salt. In some embodiments, the radioiodine in Formula I is selected from I ¹²³ , I ¹²⁴ , or I ¹³¹ . In some embodiments, the radioiodine salt is selected from a I ¹²³ , I ¹²⁴ , or I ¹³¹ salt. In some embodiments, a radioiodine or a pharmaceutically acceptable salt thereof is not I ¹²⁷ or a pharmaceutically acceptable salt thereof.

In some embodiments, the amount of radioiodine salt is at least 0.1 mCi ( e.g ., at least 0.5 mCi, at least 1 mCi, at least 1.5 mCi, at least 2 mCi, at least 2.5 mCi, at least 3 mCi, at least 3.5 mCi, at least 4 mCi, at least 4.5 mCi, at least 5 mCi, at least 6 m mCi, at least 7 mCi, at least 8 mCi, at least 9 mCi, at least 10 mCi, at least 11 mCi, at least 12 mCi, at least 13 mCi, at least 14 mCi, or at least 15 mCi). In some embodiments, the amount of radioiodine salt is at most 15 mCi (e.g., at most 0.5 mCi, at most 1 mCi, at most 1.5 mCi, at most 2 mCi, at most 2.5 mCi, at most 3 mCi, at most 3.5 mCi, at most 4 mCi, at most 4.5 mCi, at most 5 mCi, at most 6 m mCi, at most 7 mCi, at most 8 mCi, at most 9 mCi, at most 10 mCi, at most 11 mCi, at most 12 mCi, at most 13 mCi, at most 14 mCi, or at most 15 mCi). In some embodiments, the amount of radioiodine salt is between 1 mCi and 5 mCi, between 5 mCi and 10 mCi, or between 10 mCi and 15 mCi. In some embodiments, the amount of radioiodine salt is about 10 mCi, about 11 mCi, about 12 mCi, about 13 mCi, about 14 mCi, or about 15 mCi. In some embodiments, the amount of radioiodine salt is between 3 and 3.5 mCi (e.g., about 3 mCi, about 3.1 mCi, about 3.2 mCi, about 3.3 mCi, about 3.4 mCi, about 3.5 mCi).

Aspects of the present disclosure provide methods of producing a radiolabeled Hsp90 inhibitor comprising reacting substrates in the presence of peracetic acid. In some embodiments, the method of producing a compound of Formula II: comprises reacting a compound of Formula (Formula

I) with a radioiodine salt in the presence of peracetic acid, in a solution at a pH between 2-5 (e.g., at a pH between 2-3, between 3-4, between 4-5, or between 3-5). In some embodiments, the solution is at a pH of about 2, about 3, about 4, or about 5.

In some embodiments, the peracetic acid is about 3% to about 10% (e.g., 4-10%, 5- 10%, 6-10%, 7-10%, 8-10%, 9-10%, 3-4%, 3-5%, 3-6%, 3-7%, 3-8%, 3-9%, 4-5%, 4-6%, 4- 7%, 4-8%, 4-9%, 5-6%, 5-7%, 5-8%, 5-9%, 6-7%, 6-8%, 6-9%, 7-8%, 7-9%, or 8-9%) peracetic acid. In some embodiments, the peracetic acid is about 6%, 6.1%, 6.2%, 6.3%, 6.4%, 6.5%, 6.6%, 6.7%, 6.8%, 6.9%, or 7% peracetic acid. In some embodiments, the peracetic acid is 6-6.5% peracetic acid. In some embodiments, the peracetic acid is about 6.4% peracetic acid.

In some embodiments, the solution comprises phosphoric acid (H ₃ PO ₄ ) or sulfuric acid. In some embodiments, the solution comprises about 0.1- about 1 M (e.g., about 0.1 to about 0.2 M, about 0.1 to about 0.3 M, about 0.1 to about 0.4 M, about 0.1 to about 0.5 M, about 0.1 to about 0.6 M, about 0.1 to about 0.7 M, about 0.1 to about 0.8 M, about 0.1 to about 0.9 M, about 0.2 to about 0.3 M, about 0.2 to about 0.4 M, about 0.2 to about 0.5 M, about 0.2 to about 0.6 M, about 0.2 to about 0.7 M, about 0.2 to about 0.8 M, about 0.2 to about 0.9 M, about 0.2 to about 1 M, about 0.3 to about 0.4 M, about 0.3 to about 0.5 M, about 0.3 to about 0.6 M, about 0.3 to about 0.7 M, about 0.3 to about 0.8 M, about 0.3 to about 0.9 M, about or 0.3 to about 1 M, about 0.4 to about 0.5 M, about 0.4 to about 0.6 M, about 0.4 to about 0.7 M, about 0.4 to about 0.8 M, about 0.4 to about 0.9 M, about 0.4 to about 1 M, about 0.5 to about 0.6 M, about 0.5 to about 0.7 M, about 0.5 to about 0.8 M, about 0.5 to about 0.9 M, about 0.5 to about 1 M, about 0.6 to about 0.7 M, about 0.6 to about 0.8 M, about 0.6 to about 0.9 M, about 0.6 to about 1 M, about 0.7 to about 0.8 M, about 0.7 to about 0.9 M, about 0.7 to about 1 M, about 0.8 to about 0.9 M, about 0.8 to about 1 M, about or 0.9 to about 1 M) phosphoric acid (H ₃ PO ₄ ). In some embodiments, the solution comprises 0.1-lM (e.g., 0.1-0.2 M, 0.1-0.3 M, 0.1-0.4 M, 0.1-0.5 M, 0.1-0.6 M, 0.1-0.7 M, 0.1-0.8 M, 0.1-0.9 M, 0.2-0.3 M, 0.2-0.4 M, 0.2-0.5 M, 0.2-0.6 M, 0.2-0.7 M, 0.2-0.8 M, 0.2- 0.9 M, 0.2-1 M, 0.3-0.4 M, 0.3-0.5 M, 0.3-0.6 M, 0.3-0.7 M, 0.3-0.8 M, 0.3-0.9 M, or 0.3-1 M, 0.4-0.5 M, 0.4-0.6 M, 0.4-0.7 M, 0.4-0.8 M, 0.4-0.9 M, 0.4-1 M, 0.5-0.6 M, 0.5-0.7 M, 0.5-0.8 M, 0.5-0.9 M, 0.5-1 M, 0.6-0.7 M, 0.6-0.8 M, 0.6-0.9 M, 0.6- 1 M, 0.7-0.8 M, 0.7-0.9 M, 0.7-1 M, 0.8-0.9 M, 0.8-1 M, or 0.9-1 M) phosphoric acid (H ₃ PO ₄ ).

In some embodiments, the solution comprises 0.8 M H ₃ PO ₄ . In some embodiments, the solution comprises about 0.1 to about 1 M ( e.g ., (e.g., about 0.1 to about 0.2 M, about 0.1 to about 0.3 M, about 0.1 to about 0.4 M, about 0.1 to about 0.5 M, about 0.1 to about 0.6 M, about 0.1 to about 0.7 M, about 0.1 to about 0.8 M, about 0.1 to about 0.9 M, about 0.2 to about 0.3 M, about 0.2 to about 0.4 M, about 0.2 to about 0.5 M, about 0.2 to about 0.6 M, about 0.2 to about 0.7 M, about 0.2 to about 0.8 M, about 0.2 to about 0.9 M, about 0.2 to about 1 M, about 0.3 to about 0.4 M, about 0.3 to about 0.5 M, about 0.3 to about 0.6 M, about 0.3 to about 0.7 M, about 0.3 to about 0.8 M, about 0.3 to about 0.9 M, about or 0.3 to about 1 M, about 0.4 to about 0.5 M, about 0.4 to about 0.6 M, about 0.4 to about 0.7 M, about 0.4 to about 0.8 M, about 0.4 to about 0.9 M, about 0.4 to about 1 M, about 0.5 to about 0.6 M, about 0.5 to about 0.7 M, about 0.5 to about 0.8 M, about 0.5 to about 0.9 M, about 0.5 to about 1 M, about 0.6 to about 0.7 M, about 0.6 to about 0.8 M, about 0.6 to about 0.9 M, about 0.6 to about 1 M, about 0.7 to about 0.8 M, about 0.7 to about 0.9 M, about 0.7 to about 1 M, about 0.8 to about 0.9 M, about 0.8 to about 1 M, about or 0.9 to about 1 M)) sulfuric acid. In some embodiments, the solution comprises 0.8 M H ₃ PO ₄ . In some embodiments, the solution comprises 0.1-1 M (e.g., 0.1-0.2 M, 0.1-0.3 M, 0.1-0.4 M, 0.1-0.5 M, 0.1-0.6 M, 0.1-0.7 M, 0.1-0.8 M, 0.1-0.9 M, 0.2-0.3 M, 0.2-0.4 M, 0.2-0.5 M, 0.2-0.6 M, 0.2-0.7 M, 0.2-0.8 M, 0.2-0.9 M, 0.2-1 M, 0.3-0.4 M, 0.3-0.5 M, 0.3-0.6 M, 0.3-0.7 M, 0.3- 0.8 M, 0.3-0.9 M, or 0.3-1 M, 0.4-0.5 M, 0.4-0.6 M, 0.4-0.7 M, 0.4-0.8 M, 0.4-0.9 M, 0.4-1 M, 0.5-0.6 M, 0.5-0.7 M, 0.5-0.8 M, 0.5-0.9 M, 0.5-1 M, 0.6-0.7 M, 0.6-0.8 M, 0.6-0.9 M, 0.6- 1 M, 0.7-0.8 M, 0.7-0.9 M, 0.7-1 M, 0.8-0.9 M, 0.8-1 M, or 0.9-1 M) sulfuric acid.

In some embodiments, the solution comprises water.

In some embodiments, the reaction in the presence of peracetic acid occurs at a temperature between about 15 to about 30 °C (e.g., between about 15 to about 20 °C, between about 20 °C to about 30 °C, between about 20 °C to about 25 °C, between about 25 °C to about 30 °C, between about 21 °C to about 30 °C, between about 22 °C to about 30 °C, between about 23 °C to about 30 °C, between about 24 °C to about 30 °C, between about 26 °C to about 30 °C, between about 27 °C to about 30 °C, between about 28 °C to about 30 °C, or between about 29 °C to about 30 °C). In some embodiments, the reaction in the presence of peracetic acid occurs at a temperature between 15°C and 30 °C (e.g., between 15°C and 20 °C, between 20°C and 30 °C, between 20°C and 25 °C, between 25°C and 30 °C, between 21°C and 30 °C, between 22°C and 30 °C, between 23°C and 30 °C, between 24°C and 30 °C, between 26°C and 30 °C, between 27°C and 30 °C, between 28°C and 30 °C, or between 29°C and 30 °C).

In some embodiments, about the reaction occurs for about 0.5 to about 1.5 minutes (e.g., about 0.6 to about 1.5 minutes, about 0.7 to about 1.5 minutes, about 0.8 to about 1.5 minutes, about 0.9 to about 1.5 minutes, about 1 to about 1.5 minutes, about 1.1 to about 1.5 minutes, about 1.2 to about 1.5 minutes, about 1.3 to about 1.5 minutes, about 1.4 to about

1.5 minutes, about 0.5 to about 1 minute, about 0.5 to about 1.5 minutes, about or 1 to about

1.5 minutes). In some embodiments, the reaction occurs for 0.5-1.5 minutes (e.g., 0.6-1.5 minutes, 0.7-1.5 minutes, 0.8-1.5 minutes, 0.9-1.5 minutes, 1-1.5 minutes, 1.1-1.5 minutes, 1.2-1.5 minutes, 1.3-1.5 minutes, 1.4-1.5 minutes, 0.5-1 minute, or 1-1.5 minutes).

In some embodiments, the method further adding, to the reaction mixture, sodium metabisulfite in saturated sodium bicarbonate (NaHCO,) following the reaction (e.g., following about 0.5 to about 1.5 minutes (e.g., about 0.6 to about 1.5 minutes, about 0.7 to about 1.5 minutes, about 0.8 to about 1.5 minutes, about 0.9 to about 1.5 minutes, about 1 to about 1.5 minutes, about 1.1 to about 1.5 minutes, about 1.2 to about 1.5 minutes, about 1.3 to about 1.5 minutes, about 1.4 to about 1.5 minutes, about 0.5 to about 1 minute, about or 1 to about 1.5 minutes) of incubating the substrates). In some embodiments, the method further comprises adding, to the reaction mixture, sodium metabisulfite in saturated sodium bicarbonate (NaHCO ¹ ,) following the reaction (e.g., following 0.5 to 1.5 minutes (e.g., 0.6 to

1.5 minutes, 0.7 to 1.5 minutes, 0.8 to 1.5 minutes, 0.9 to 1.5 minutes, 1 to 1.5 minutes, 1.1 to 1.5 minutes, 1.2 to 1.5 minutes, 1.3 to 1.5 minutes, 1.4 to 1.5 minutes, 0.5 to 1 minute, or 1 to 1.5 minutes) of incubating the substrates).

Any of the methods of producing a radiolabeled Hsp90 inhibitor disclosed herein may further comprise purifying the compound of Formula II from the reaction mixture. In some embodiments, the compound of Formula II is recovered at about 5%, 10%, 15%, 20%, 25%, 30%, 40%, 50%, 60%, 70%, 75%, 80%, 85%, 90%, or 95% yield. In some embodiments, the compound of Formula II is recovered at a particular percentage (e.g., least 5%, at least 10%, at least 15%, at least 20%, at least 25%, at least 30%, at least 40%, at least 50%, at least 60%, at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, or at least 95% yield). In some embodiments, the percentage yield is determined by measuring the mass of a product ( e.g ., a radiolabeled Hsp90 inhibitor) relative to the mass of the starting materials (e.g., a tin- labeled Hsp90 inhibitor).

In some embodiments, the specific activity of the compound of Formula II is at least 10 mCi/mg (e.g., at least 15 mCi/mg, at least 20 mCi/mg, at least 25 mCi/mg, at least 30 mCi/mg, at least 35 mCi/mg, or at least 40 mCi/mg). In some embodiments, the specific activity of the compound of Formula II is at most 50 mCi/mg (e.g., at most 15 mCi/mg, at most 20 mCi/mg, at most 25 mCi/mg, at most 30 mCi/mg, at most 35 mCi/mg, or at most 40 mCi/mg).

In some embodiments, the method of producing a compound of: (Formula II), comprises reacting:

(a) a compound of Formula I: (Formula I);

(b) chloramine-T; and

(c) a radioiodine salt, wherein the ratio of the mass of chloramine-T to the mass of the compound of Formula I in the reaction is about 3 to about 5, thereby forming a reaction mixture. For example, 25 μg of a compound of Formula I may be used with 15 pg chloramine-T.

In some embodiments, the reaction further comprises a phosphate buffer, optionally at a pH of about 7.

In some embodiments, the compound of Formula II is recovered at about 5%, 10%, 15%, 20%, 25%, 30%, 40%, 50%, 60%, 70%, 75%, 80%, 85%, 90%, or 95% yield. In some embodiments, the compound of Formula II is recovered at least 5%, at least 10%, at least 15%, at least 20%, at least 25%, at least 30%, at least 40%, at least 50%, at least 60%, at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, or at least 95% yield. In some embodiments, the compound of Formula II is recovered at most 5%, at most 10%, at most 15%, at most 20%, at most 25%, at most 30%, at most 40%, at most 50%, at most 60%, at most 70%, at most 75%, at most 80%, at most 85%, at most 90%, or at most 95% yield. In some embodiments, the percentage yield is determined by measuring the mass of a product ( e.g ., a radiolabeled Hsp90 inhibitor) relative to the mass of the starting materials (e.g., a tin- labeled Hsp90 inhibitor). In some embodiments, the yield of Formula II using a method described herein is increased by at least 5% (e.g., at least 10%, at least 15%, at least 20%, at least 25%, at least 30%, at least 35%, at least 40%, at least 45%, at least 50%, at least 55%, at least 60%, at least 65%, at least 70%, at least 80%, at least 90%, at least 95%, at least 100%, at least 200%, at least 300%, at least 400%, at least 500%, at least 600%, at least 700%, at least 800%, at least 900%, or at least 1,000%) as compared to a control. In some embodiments, a control is performed using the same reaction but with a different ratio of the mass of chloramine-T to the mass of Formula I in the reaction (e.g., a ratio that is not 3:5).

In some embodiments, the compound of Formula I is provided in ethanol.

In some embodiments, the compound of Formula I and chloramine-T are provided in a pre-mixed solution. In some embodiments, the pre-mixed solution further comprises acetic acid. In some embodiments, the compound of Formula I and chloramine-T are not provided in a pre-mixed solution.

In some embodiments, the method further comprises passing the reaction mixture through a column (e.g., a Sep-Pak) and eluting the product with less than 3 mL (e.g., less than 2.9 m., less than 2.8 ml, less than 2.7 ml, less than 2.6 ml, less than 2.7 ml, less than 2.6 ml, less than 2.5 ml, less than 2.4 ml, less than 2.3 ml, less than 2.2 ml, less than 2.1 ml, less than 2 ml, less than 1.5 ml, less than 1 ml, or less than 0.5 ml) of pure ethanol. In some embodiments, the product comprises a compound of Formula II.

In some embodiments, the radioiodine salt is provided in about 0.01 M NaOH. In some embodiments, the radioiodine salt is provided in about 0.005 to about 0.05 M NaOH.

Additional Methods

Additional examples of compounds of Hsp90 inhibitors that may be used for Sn- labeling and/or radiolabeling are provided in US published application US 2009/0298857 Al, International Application Publication No. WO 2018/200534 Al, and in US Patent No. 7834181, the entire disclosures of which as they relate to such Hsp90 inhibitors and classes thereof are incorporated by reference herein.

Reference can also be made to PCT Publication No. WO2011/044394 (Application No. PCT/US2010/051872) and US Patent No. 9,994,573 for additional compounds that can be used as Hsp90 inhibitors and that are contemplated as part of this disclosure. The teachings of such reference are incorporated by reference herein.

Any of the methods described herein may comprise purifying a compound of interest. In some embodiments, purifying a compound comprises distillation, chromatography, crystallization, filtration, or any combination thereof. Chromatography may comprise a normal phase, reverse phase, or ion-exchange elution over a cartridge comprising suitable sorbent media. In some embodiments, chromatography comprises high performance liquid chromatography (HPLC). A chromatography method may use one or more solvents, e.g., one or more known solvents or one or more solvents determined by routine experimentation. Non-limiting examples of solvents that are suitable for use with HPLC include acetonitrile (MeCN), ethanol (EtOH), methanol (MeOH), and trifluoroacetic acid (TFA). Any of the solvents may be prepared in a solution, e.g., TFA in deionized, Milli-Q or HPLC grade water. In some embodiments, HPLC comprises two mobile phases (see, e.g., Example 1 below).

Any of the methods described herein may result in a product purity of at least 1%, at least 15%, at least 10%, at least 15%, at least 20%, at least 25%, at least 30%, at least 35%, at least 40%, at least 45%, at least 50%, at least 55%, at least 60%, at least 65%, at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 95%, or 100%. Product purity may be measured using known methods including HPLC. Product purity may be measured as the mass of the compound of interest relative to the entire mass of the product produced. See, e.g., the methods described in Example 1 below.

Kits

Also encompassed by the disclosure are kits (e.g., pharmaceutical packs). The kits provided may comprise a pharmaceutical composition (i.e., pharmaceutical formulation) or compound described herein and a container (e.g., a vial, ampule, bottle, syringe, and/or dispenser package, or other suitable container). In some embodiments, provided kits may optionally further include a second container comprising a pharmaceutical excipient for dilution or suspension of a pharmaceutical composition or compound described herein. In some embodiments, the pharmaceutical composition or compound described herein provided in the first container and the second container are combined to form one unit dosage form.

In certain embodiments, the kits are useful for producing a Sn-labeled Hsp90 inhibitor and/or a radiolabeled Hsp90 inhibitor. In some embodiments, a kit further comprises instructions for producing a Sn-labeled Hsp90 inhibitor and/or radiolabeled Hsp90 inhibitor using a method described herein. In some embodiments, a kit further comprises instructions for use of a compound disclosed herein (e.g., a radiolabeled Hsp90 inhibitor disclosed herein).

In some embodiments, a kit comprises a compound of Formula V: (Formula V) and hexamethylditin (Sn ₂ Me ₆ ) and tris(dibenzylideneacetone)dipalladium(0) (Pd ₂ (dba) ₃ ).

In some embodiments, a kit comprises a compound of Formula I as defined herein, phosphoric acid (H ₃ PO ₄ ), and peracetic acid. In some embodiments, the kit further comprises a radioiodine salt. In some embodiments, the kit does not comprise a radioiodine salt. In some embodiments, the radioiodine salt is sodium radioiodine. In some embodiments, the kit comprises about 0.1 to about 1 M ( e.g ., (e.g., about 0.1 to about 0.2 M, about 0.1 to about 0.3 M, about 0.1 to about 0.4 M, about 0.1 to about 0.5 M, about 0.1 to about 0.6 M, about 0.1 to about 0.7 M, about 0.1 to about 0.8 M, about 0.1 to about 0.9 M, about 0.2 to about 0.3 M, about 0.2 to about 0.4 M, about 0.2 to about 0.5 M, about 0.2 to about 0.6 M, about 0.2 to about 0.7 M, about 0.2 to about 0.8 M, about 0.2 to about 0.9 M, about 0.2 to about 1 M, about 0.3 to about 0.4 M, about 0.3 to about 0.5 M, about 0.3 to about 0.6 M, about 0.3 to about 0.7 M, about 0.3 to about 0.8 M, about 0.3 to about 0.9 M, about or 0.3 to about 1 M, about 0.4 to about 0.5 M, about 0.4 to about 0.6 M, about 0.4 to about 0.7 M, about 0.4 to about 0.8 M, about 0.4 to about 0.9 M, about 0.4 to about 1 M, about 0.5 to about 0.6 M, about 0.5 to about 0.7 M, about 0.5 to about 0.8 M, about 0.5 to about 0.9 M, about 0.5 to about 1 M, about 0.6 to about 0.7 M, about 0.6 to about 0.8 M, about 0.6 to about 0.9 M, about 0.6 to about 1 M, about 0.7 to about 0.8 M, about 0.7 to about 0.9 M, about 0.7 to about 1 M, about 0.8 to about 0.9 M, about 0.8 to about 1 M, about or 0.9 to about 1 M)) sulfuric acid. In some embodiments, the solution comprises 0.8 M H ₃ PO ₄ . In some embodiments, the solution comprises 0.1-1 M ( e.g ., 0.1-0.2 M, 0.1-0.3 M, 0.1-0.4 M, 0.1-0.5 M, 0.1-0.6 M, 0.1-0.7 M, 0.1-0.8 M, 0.1-0.9 M, 0.2-0.3 M, 0.2-0.4 M, 0.2-0.5 M, 0.2-0.6 M, 0.2-0.7 M, 0.2-0.8 M, 0.2-0.9 M, 0.2-1 M, 0.3-0.4 M, 0.3-0.5 M, 0.3-0.6 M, 0.3-0.7 M, 0.3- 0.8 M, 0.3-0.9 M, or 0.3-1 M, 0.4-0.5 M, 0.4-0.6 M, 0.4-0.7 M, 0.4-0.8 M, 0.4-0.9 M, 0.4-1 M, 0.5-0.6 M, 0.5-0.7 M, 0.5-0.8 M, 0.5-0.9 M, 0.5-1 M, 0.6-0.7 M, 0.6-0.8 M, 0.6-0.9 M, 0.6- 1 M, 0.7-0.8 M, 0.7-0.9 M, 0.7-1 M, 0.8-0.9 M, 0.8-1 M, or 0.9-1 M) sulfuric acid. In some embodiments, the kit comprises 0.8 M phosphoric acid (H ₃ PO ₄ ). In some embodiments, the kit further comprises sodium metabisulfite. In some embodiments, the sodium metabisulfite is in saturated sodium bicarbonate (NaHCO ₃ ).

In some embodiments, the peracetic acid is about 3% to about 10% (e.g., 4-10%, 5- 10%, 6-10%, 7-10%, 8-10%, 9-10%, 3-4%, 3-5%, 3-6%, 3-7%, 3-8%, 3-9%, 4-5%, 4-6%, 4- 7%, 4-8%, 4-9%, 5-6%, 5-7%, 5-8%, 5-9%, 6-7%, 6-8%, 6-9%, 7-8%, 7-9%, or 8-9%) peracetic acid. In some embodiments, the peracetic acid is about 6%, about 6.1%, about 6.2%, about 6.3%, about 6.4%, about 6.5%, about 6.6%, about 6.7%, about 6.8%, about 6.9%, or about 7% peracetic acid. In some embodiments, the peracetic acid is 6-6.5% peracetic acid. In some embodiments, the peracetic acid is about 6.4% peracetic acid.

In some embodiments, the kit further comprises a syringe, Sep-Pak, and/or ethanol.

In some embodiments, the radioiodine salt is a salt of I ¹²³ , I ¹²⁴ , or I ¹³¹ .

In some embodiments, a kit comprises a compound of Formula I as defined herein and chloramine-T, in which the ratio of the mass of chloramine-T to the mass of Formula I in the reaction is about 3 to about 5. In some embodiments, the kit further comprises phosphate buffer at about pH 7. The compound of Formula I and chloramine-T may be provided in the same container or in separate containers. In some embodiments, the compound of Formula I and chloramine-T are provided in the same container that also comprises acetic acid. In some embodiments, the compound of Formula I is provided in ethanol in a container that is different from the container comprising chloramine-T. In some embodiments, the kit further comprises: i) ethanol; ii) water; iii) a reaction container; iv) a waste container; v) a product container; vi) a Sep-Pak; vii) one or more syringes; and/or viii) one or more stopcocks. In some embodiments, the kit further comprises a radioiodine salt. In some embodiments, the radioiodine salt is sodium radioiodine. In some embodiments, the radioiodine salt is a salt of I ¹²³ , I ¹²⁴ , or I ¹³¹ . Thus, in one aspect, provided are kits including a first container comprising a compound or pharmaceutical composition described herein. In certain embodiments, the kits are useful for treating a disease ( e.g ., cancer, neurodegenerative disorder, inflammation or inflammatory condition, autoimmune disease) in a subject in need thereof. In certain embodiments, the kits are useful for preventing a disease (e.g., cancer, neurodegenerative disorder, inflammation or inflammatory condition, autoimmune disease) in a subject in need thereof. In certain embodiments, the kits are useful for reducing the risk of developing a disease (e.g., cancer, neurodegenerative disorder, inflammation or inflammatory condition, autoimmune disease) in a subject in need thereof. In certain embodiments, the kits are useful for inhibiting the activity (e.g., aberrant activity, such as increased activity) of a Hsp90 protein in a subject or cell.

In certain embodiments, a kit described herein further includes instructions for using the kit. A kit described herein may also include information as required by a regulatory agency such as the U.S. Food and Drug Administration (FDA). In certain embodiments, the information included in the kits is prescribing information. In certain embodiments, the kits and instructions provide for treating a disease (e.g., cancer, neurodegenerative disorder, inflammation or inflammatory condition, autoimmune disease) in a subject in need thereof. In certain embodiments, the kits and instructions provide for preventing a disease (e.g., cancer, neurodegenerative disorder, inflammation or inflammatory condition, autoimmune disease) in a subject in need thereof. In certain embodiments, the kits and instructions provide for reducing the risk of developing a disease (e.g., cancer, neurodegenerative disorder, inflammation or inflammatory condition, autoimmune disease) in a subject in need thereof. In certain embodiments, the kits and instructions provide for inhibiting the activity (e.g., aberrant activity, such as increased activity) of a Hsp90 protein in a subject or cell. In some instances, the kits and instructions provide for assessment of epichaperome levels and/or to identify subjects that may be sensitive (and thus responsive) to treatment with an epichaperone inhibitor. For example, the kits and instructions may provide for determination of epichaperome levels and identification patients that would respond to treatment with epichaperome inhibitors (e.g., Hsp90 inhibitors) and can be used to follow and evaluate treatment effects by PET scans to assess the epichaperome level, or size of a tumor, or extent of neurodegenerative diseases. A kit described herein may include one or more additional pharmaceutical agents described herein as a separate composition. Subjects and Indications

The subjects to be administered a radiolabeled Hsp90 produced by a method provided herein include mammals such as humans and animals such as non-human primates, agricultural animals (e.g., cow, pig, sheep, goat, horse, rabbit, etc.), companion animals (e.g., dog, cat, etc.), and rodents (e.g., rat, mouse, etc.). Preferred subjects are human subjects. Subjects may be referred to herein as patients in some instances.

In some embodiments, the active compounds and formulations provided herein are intended for use in subjects in need of Hsp90 inhibition. Such subjects may have or may be at risk of developing a condition characterized by the presence of epichaperomes or the elevated (compared to normal cells) presence of Hsp90 or which may benefit from inhibition of Hsp90 activity. Such conditions may be characterized by the presence of misfolded proteins. Such conditions include without limitation cancer, neurodegenerative disorder, inflammation (or inflammatory conditions) such as but not limited to cardiovascular diseases (e.g., atherosclerosis), autoimmune diseases, and the like.

The compounds and formulations provided herein may be administered via any standard route of administration including but not limited to intraveous administration.

As a non-limiting example, a radiolabeled Hsp90 inhibitor may be used to treat cancer. In some instances, the radiolabeled Hsp90 inhibitor is administered locally to treat glioblastoma. In some instances, the radiolabeled Hsp90 inhibitor is ¹³¹ I.

A therapeutically effective amount of one or more active compounds disclosed herein may be provided in a formulation. The term "therapeutically effective amount" refers to an amount of an active compound or a combination of two or more compounds that inhibits, totally or partially, the progression of the condition being treated or alleviates, at least partially, one or more symptoms of the condition. For example, the compounds may be an Hsp90 inhibitor and a second therapeutic agent, and in some embodiments the therapeutically effective amount is the amount of these two classes of agents when used together (including for example the amount of each class of agent). A therapeutically effective amount can also be an amount which is prophylactically effective when given, for example, to a subject at risk of developing the condition or a subject who has been successfully treated but may be at risk of a recurrence. The amount which is therapeutically effective depends on the patient's gender and size, the condition to be treated, the condition's severity, and the result sought.

For a given patient, a therapeutically effective amount can be determined by methods known to those in the art. Dosage strength, as used herein, refers to the amount of active compound in a single dose formulation (e.g., a single capsule, intravenous dose, or a single tablet, etc.). Dosages may range from about 0.001 to about 1000 mg, including about 0.01 mg to about 1000 mg, including 0.01 mg to about 1000 mg, including about 1 mg to about 1000 mg of Hsp90 inhibitor. Exemplary dosage strengths include at least 0.001, at least 0.005, at least 0.01, at least 0.05, at least 0.1, at least 0.5, at least 1 mg, at least 2 mg, at least 3 mg, at least 4 mg, at least 5 mg, at least 10 mg, at least 15 mg, at least 20 mg, at least 25 mg, at least 30 mg, at least 35 mg, at least 40 mg, at least 45 mg, at least 50 mg, at least 55 mg, at least 60 mg, at least 65 mg, at least 70 mg, at least 75 mg, at least 80 mg, at least 85 mg, at least 90 mg, at least 95 mg, at least 100 mg, at least 125 mg, at least 150 mg, at least 175 mg, at least 200 mg, at least 300 mg, at least 400 mg, at least 500 mg or more of Hsp90 inhibitor. Exemplary dosage strengths include 0.001 mg, 0.005 mg, 0.01 mg, 0.05 mg, 0.1 mg, 0.5 mg, 1 mg, 2 mg, 3 mg, 4 mg, 5 mg, 10 mg, 15 mg, 20 mg, 25 mg, 30 mg, 35 mg, 40 mg, 45 mg, 50 mg, 55 mg, 60 mg, 65 mg, 70 mg, 75 mg, 80 mg, 85 mg, 90 mg, 95 mg, 100 mg, 125 mg, 150 mg, 175 mg, 200 mg, 300 mg, 400 mg, 500 mg, or more, of Hsp90 inhibitor, including all doses therebetween as is explicitly recited herein. In some instances, when a large dose is required, several of a smaller dosage form may be administered or a single larger dosage form may be administered.

The formulations may be administered daily, every 2 days, every 3 days, every 4 days, every 5 days, every 6 days, every week, every 2 weeks, every 3 weeks, every 4 weeks, every month, every 2 months, every 3 months, every 4 months, every 6 months, or every year.

The formulations provided herein may be administered for a period of time (referred to as a treatment period) followed by a period of time in which the formulations are not administered to the subjects (referred to herein as a non-treatment period). The treatment period may be 1, 2, 3, 4, 5, 6 or 7 days and the non-treatment period may be 1, 2, 3, 4, 5, 6, or 7 or more days. Alternatively, the treatment period may be 1, 2, 3 or 4 weeks and the nontreatment period may be 1, 2, 3, 4 or more weeks. The non-treatment period may be as long as or 2, 3, 4, 5, 6, 7, 8, 9 or 10 times as long as the treatment period. The treatment and nontreatment periods may be repeated 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10 or more times. In some embodiments, the treatment period is 1 week and the non-treatment period is 3 weeks, and these are repeated 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10 or more times. The formulations provided herein may be administered once a day, twice a day, or thrice a day. The formulations provided herein may be administered every 3 hours, every 4 hours, every 6 hours, every 12 hours, or every 24 hours.

Cancer

The term "cancer" or "neoplastic disorder" refers to a tumor resulting from abnormal or uncontrolled cellular growth. Examples of cancers include but are not limited to breast cancers (e.g., ER+/HER2- breast cancer, ER+/HER2+ breast cancer, ER-/HER2+ breast cancer, triple negative breast cancer, etc.) , colon cancers, colorectal cancers, prostate cancers, ovarian cancers, pancreatic cancers, lung cancers, gastric cancers, esophageal cancers, glioma cancers, and hematologic malignancies. In some instances, the cancer is glioblastoma. Examples of neoplastic disorders include but are not limited to hematopoietic disorders, such as the myeloproliferative disorders, essential thrombocytosis, thrombocythemia, angiogenic myeloid metaplasia, polycythemia vera, myelofibrosis, myelofibrosis with myeloid metaplasia, chronic idiopathic myelofibrosis, the cytopenias, and pre-malignant myelodysplastic syndromes. In some instances, the indication to be treated is pancreatic cancer, breast cancer, prostate cancer, skin cancer (e.g., melanoma, basal cell carcinoma), B cell lymphoma, Hodgkin's lymphoma, and non-Hodgkin's lymphoma. In some instances, the indication to be treated is pancreatic cancer. In some instances, the indication to be treated is breast cancer. The cancer to be treated may be a primary cancer (without indication of metastasis) or a metastatic stage cancer.

The term "hematologic malignancy" refers to cancer of the bone marrow and lymphatic tissue -body's blood-forming and immune system. Examples of hematological malignancies include but are not limited to myelodysplasia, lymphomas, leukemias, lymphomas (non-Hodgkin's lymphoma), Hodgkin's disease (also known as Hodgkin's lymphoma), and myeloma, such as acute lymphocytic leukemia (ALL), adult T-cell ALL, acute myeloid leukemia (AML), AML with trilineage myelodysplasia, acute promyelocytic leukemia, acute undifferentiated leukemia, anaplastic large-cell lymphoma, chronic lymphocytic leukemia, chronic myeloid leukemia, chronic neutrophilic leukemia, juvenile myelomonocyctic leukemia, mixed lineage leukemia, myeloproliferative disorders, myelodysplastic syndromes, multiple myeloma, and prolymphocytic leukemia.

Neurodegenerative disorder The term "neurodegenerative disorder" refers to a disorder in which progressive loss of neurons occurs either in the peripheral nervous system or in the central nervous system. Examples of neurodegenerative disorders include but are not limited to chronic neurodegenerative diseases such as diabetic peripheral neuropathy, Alzheimer's disease,

Pick's disease, diffuse Lewy body disease, progressive supranuclear palsy (Steel-Richardson syndrome), multisystem degeneration (Shy-Drager syndrome), motor neuron diseases including amyotrophic lateral sclerosis ("ALS"), degenerative ataxias, cortical basal degeneration, ALS-Parkinson's-Dementia complex of Guam, subacute sclerosing panencephalitis, Huntington's disease, Parkinson's disease, multiple sclerosis, synucleinopathies, primary progressive aphasia, striatonigral degeneration, Machado- Joseph disease/spinocerebellar ataxia type 3 and olivopontocerebellar degenerations, Gilles De La Tourette's disease, bulbar and pseudobulbar palsy, spinal and spinobulbar muscular atrophy (Kennedy's disease), primary lateral sclerosis, familial spastic paraplegia, Wemicke- Korsakoff s related dementia (alcohol induced dementia), Werdnig-Hoffmann disease, Kugelberg-Welander disease, Tay-Sach's disease, Sandhoff disease, familial spastic disease, Wohifart-Kugelberg-Welander disease, spastic paraparesis, progressive multifocal leukoencephalopathy, and prion diseases (including Creutzfeldt- Jakob, Gerstmann- Straussler-Scheinker disease, Kuru and fatal familial insomnia).

Other conditions also included within the methods of the present disclosure include age-related dementia and other dementias, tauopathies, and conditions with memory loss including vascular dementia, diffuse white matter disease (Binswanger's disease), dementia of endocrine or metabolic origin, dementia of head trauma, chronic traumatic encephalopathy, and diffuse brain damage, dementia pugilistica, and frontal lobe dementia. Also other neurodegenerative disorders resulting from cerebral ischemia or infarction including embolic occlusion and thrombotic occlusion as well as intracranial hemorrhage of any type (including but not limited to epidural, subdural, subarachnoid, and intracerebral), and intracranial and intravertebral lesions (including but not limited to contusion, penetration, shear, compression, and laceration).

Thus, the term "neurodegenerative disorder" also encompasses acute neurodegenerative disorders such as those involving stroke, traumatic brain injury, chronic traumatic encephalopathy, schizophrenia, peripheral nerve damage, hypoglycemia, spinal cord injury, epilepsy, anoxia, and hypoxia.

In certain embodiments, the neurodegenerative disorder is selected from Alzheimer's disease, Parkinson's disease, Huntington disease, amyotrophic lateral sclerosis, complete androgen insensitivity syndrome (CAIS), spinal and bulbar muscular atrophy (SBMA or Kennedy's disease), sporadic frontotemporal dementia with parkinsonism (FTDP), familial FTDP-17 syndromes, age-related memory loss, senility, and age-related dementia. In another embodiment, the neurodegenerative disorder is Alzheimer's disease, also characterized as an amyloidosis. Thus, other embodiments of the disclosure relate to the treatment or prevention of other amyloidosis disorders which share features, including, but not limited to, hereditary cerebral angiopathy, normeuropathic hereditary amyloid, Down's syndrome, macroglobulinemia, secondary familial Mediterranean fever, Muckle- Wells syndrome, multiple myeloma, pancreatic- and cardiac-related amyloidosis, chronic hemodialysis arthropathy, Finnish amyloidosis, and Iowa amyloidosis.

Inflammation (or Inflammatory conditions)

The Hsp90 inhibitors of this disclosure may be used in the treatment of inflammation (or inflammatory conditions). Examples of inflammatory conditions include cardiovascular diseases and autoimmune diseases.

Non-autoimmune inflammatory disorders are inflammatory disorders that are not autoimmune disorders. Examples include atherosclerosis, myocarditis, myocardial infarction, ischemic stroke, abscess, asthma, some inflammatory bowel diseases, chronic obstructive pulmonary disease (COPD), allergic rhinitis, non-autoimmune vasculitis (e.g. polyarteritis nodosa), age related macular degeneration, alcoholic liver disease, allergy, allergic asthma, anorexia, aneurism, aortic aneurism, atopic dermatitis, cachexia, calcium pyrophosphate dihydrate deposition disease, cardiovascular effects, chronic fatigue syndrome, congestive heart failure, comeal ulceration, enteropathic arthropathy, Felty's syndrome, fever, fibromyalgia syndrome, fibrotic disease, gingivitis, glucocorticoid withdrawal syndrome, gout, hemorrhage, viral (e.g., influenza) infections, chronic viral (e.g., Epstein-Barr, cytomegalovirus, herpes simplex virus) infection, hyperoxic alveolar injury, infectious arthritis, intermittent hydrarthrosis, Lyme disease, meningitis, mycobacterial infection, neovascular glaucoma, osteoarthritis, pelvic inflammatory disease, periodontitis, polymyositis/dermatomyositis, post-ischaemic reperfusion injury, post-radiation asthenia, pulmonary emphysema, pydoderma gangrenosum, relapsing polychondritis, Reiter's syndrome, sepsis syndrome, Still's disease, shock, Sjogren's syndrome, skin inflammatory diseases, stroke, non-autoimmune ulcerative colitis, bursitis, uveitis, osteoporosis,

Alzheimer's disease, ataxia telangiectasia, non-autoimmune vasculitis, non-autoimmune arthritis, bone diseases associated with increased bone resorption, ileitis, Barrett's syndrome, inflammatory lung disorders, adult respiratory distress syndrome, and chronic obstructive airway disease, inflammatory disorders of the eye including corneal dystrophy, trachoma, onchocerciasis, sympathetic ophthalmitis and endophthalmitis, chronic inflammatory disorders of the gums such as gingivitis, tuberculosis, leprosy, inflammatory diseases of the kidney including uremic complications, glomerulonephritis and nephrosis, inflammatory disorders of the skin including sclerodermatitis and eczema, inflammatory diseases of the central nervous system, including chronic demyelinating diseases of the nervous system, AIDS-related neurodegeneration and Alzheimer's disease, infectious meningitis, encephalomyelitis, Parkinson's disease, Huntington's disease, amyotrophic lateral sclerosis and viral or autoimmune encephalitis, immune-complex vasculitis, erythematodes, and inflammatory diseases of the heart such as cardiomyopathy, ischemic heart disease, hypercholesterolemia, as well as various other diseases with significant inflammatory components, including preeclampsia, chronic liver failure, septic shock, haemodynamic shock, sepsis syndrome, malaria, diseases involving angiogenesis, skin inflammatory diseases, radiation damage, hyperoxic alveolar injury, periodontal disease, non-insulin dependent diabetes mellitus, and brain and spinal cord trauma.

Cardiovascular diseases

The Hsp90 inhibitors of this disclosure may be used in the treatment of cardiovascular diseases. Examples of cardiovascular diseases (or conditions) include atherosclerosis, elevated blood pressure, heart failure or a cardiovascular event such as acute coronary syndrome, myocardial infarction, myocardial ischemia, chronic stable angina pectoris, unstable angina pectoris, angioplasty, stroke, transient ischemic attack, claudication(s), or vascular occlusion(s).

Autoimmune diseases

The Hsp90 inhibitors of this disclosure may be used in the treatment of autoimmune diseases. Examples of autoimmune diseases include but are not limited to multiple sclerosis, inflammatory bowel disease including Crohn's Disease and ulcerative colitis, rheumatoid arthritis, psoriasis, type I diabetes, uveitis, Celiac disease, pernicious anemia, Srojen's syndrome, Hashimoto's thyroiditis, Graves' disease, systemic lupus erythamatosis, acute disseminated encephalomyelitis, Addison's disease, Ankylosing spondylitis, antiphospholipid antibody syndrome, Guillain-Barre syndrome, idiopathic thrombocytopenic purpura, Goodpasture's syndrome, Myasthenia gravis, Pemphigus, giant cell arteritis, aplastic anemia, autoimmune hepatitis, Kawaski's disease, mixed connective tissue disease, Ord throiditis, polyarthritis, primary biliary sclerosis, Reiter's syndrome, Takaysu's arteritis, vitiligo, warm autoimmune hemolytic anemia, Wegener's granulomatosis, Chagas' disease, chronic obstructive pulmonary disease, and sarcoidosis.

Secondary therapeutic agents

The Hsp90 inhibitors of this disclosure may be used in combination with one or more other therapeutic agents, referred to herein as secondary therapeutic agents. The Hsp90 inhibitors and secondary therapeutic agents may have an additive effect or a synergistic (i.e., greater than additive) effect on the targeted indication.

Examples of secondary therapeutic agents include angiogenesis inhibitors, pro- apoptotic agents, cell cycle arrest agents, kinase inhibitors, AKT inhibitors, BTK inhibitors, Bcl2 inhibitors, SYK inhibitors, CD40 inhibitors, CD28 pathway inhibitors, MHC class II inhibitors, PI3K inhibitors, mTOR inhibitors, JAK inhibitors, IKK inhibitors, Raf inhibitors, SRC inhibitors, phosphodiesterase inhibitors, ERK-MAPK pathway inhibitors, and the like.

Examples of AKT inhibitors include PF-04691502, Triciribine phosphate (NSC- 280594), A-674563, CCT128930, AT7867, PHT-427, GSK690693, MK-2206 dihydrochloride.

Examples of BTK inhibitors include PCI-32765.

Examples of Bcl2 inhibitors include ABT-737, Obatoclax (GX15-070), ABT-263.

TW-37 Examples of SYK inhibitors include R-406, R406, R935788 (Fostamatinib disodium).

Examples of CD40 inhibitors include SGN-40 (anti-huCD40 mAb).

Examples of inhibitors of the CD28 pathway include abatacept, belatacept, blinatumomab, muromonab-CD3, visilizumab.

Examples of inhibitors of major histocompatibility complex, class II include apolizumab.

Examples of PI3K inhibitors include 2-(lH-indazol-4-yl)-6-(4- methanesulfonylpiperazin-l-ylmethyl)-4-morpholin-4-ylthieno( 3,2-d)pyrimidine, BKM120, NVP-BEZ235, PX-866, SF 1126, XL147.

Example of mTOR inhibitors include deforolimus, everolimus, NVP-BEZ235, OST 027, tacrolimus, temsirolimus, Ku-0063794, WYE-354, PP242, OSI-027, GSK2126458, WAY-600, WYE- 125132. Examples of JAK inhibitors include Tofacitinib citrate (CP-690550), AT9283, AG- 490, INCBO 18424 (Ruxolitinib), AZD1480, LY2784544, NVP-BSK805, TGI 01209, TG- 101348.

Examples of IkK inhibitors include SC-514, PF 184.

Examples of inhibitors of Raf include sorafenib, vemurafenib, GDC-0879, PLX-4720, PLX4032 (Vemura/enib), NVP-BHG712, SB590885, AZ628, ZM 336372.

Examples of inhibitors of SRC include AZM-475271, dasatinib, saracatinib.

Examples of inhibitors of phosphodiesterases include aminophylline, anagrelide, arofylline, caffeine, cilomilast, dipyridamole, dyphylline, L 869298, L-826,141, milrinone, nitroglycerin, pentoxifylline, roflumilast, rolipram, tetomilast, theophylline, tolbutamide, amrinone, anagrelide, arofylline, caffeine, cilomilast, L 869298, L-826,141, milrinone, pentoxifylline, roflumilast, rolipram, tetomilast.

Other secondary therapeutic agents that can be used in combination with the Hsp90 inhibitors of this disclosure include AQ4N, becatecarin, BN 80927, CPI-0004Na, daunombicin, dexrazoxane, doxorubicin, elsamitrucin, epirubicin, etoposide, gatifloxacin, gemifloxacin, mitoxantrone, nalidixic acid, nemorubicin, norfloxacin, novobiocin, pixantrone, tafluposide, TAS-103, tirapazamine, valrubicin, XK469, BI2536.

Still other secondary therapeutic agents are nucleoside analogs. Examples include (1) deoxyadenosine analogues such as didanosine (ddl) and vidarabine; (2) adenosine analogues such as BCX4430; (3) deoxycytidine analogues such as cytarabine, gemcitabine, emtricitabine (FTC), lamivudine (3TC), and zalcitabine (ddC); (4) guanosine and deoxyguanosine analogues such as abacavir, acyclovir, and entecavir; (5) thymidine and deoxythymidine analogues such as stavudine (d4T), telbivudine, zidovudine (azidothymidine, or AZT); and (6) deoxyuridine analogues such as idoxuridine and trifluridine.

Other secondary therapeutic agents include taxanes such as paclitaxel, dicetaxel, cabazitaxel. Other secondary therapeutic agents include inhibitors of other heatshock proteins such as of Hsp70, Hsp60, and Hsp26.

Still other secondary therapeutic agents that can be used in combination with the Hsp90 inhibitors of this disclosure are disclosed in published PCT Application No. WO ₂ 012/149493, the entire disclosure of which as it relates to such secondary therapeutic agents and classes thereof is incorporated by reference herein.

The Hsp90 inhibitors and the secondary therapeutic agents may be co-administered. Co-administered includes administering substantially simultaneously, concomitantly, sequentially or adjunctively. The Hsp90 inhibitors and the secondary therapeutic agents may be administered at different times. For example, the Hsp90 inhibitors may be administered before or after the secondary therapeutic agent including one or more hours before, one or more day before, or one or more week before the secondary therapeutic agents. One or more secondary therapeutic agents may be used. Each of the therapeutic agents may be administered at their predetermined optimal frequency and dose. In some instances, the Hsp90 inhibitors and the secondary therapeutic agents are administered in combination in a therapeutically effective amount.

EXAMPLES

Example 1.

This Example describes production of Compound 2, a non-limiting example of an Sn- labeled Hsp90 inhibitor, using Pd ₂ (dba) ₃ as a catalyst. A schematic of the synthesis is shown in FIG. 1. Compound 2 was prepared in three steps from Compound 7 including one synthetic step and two purification steps. Compound 7 was coupled with hexamethylditin via a Stille reaction using Pd2(dba)3 as a catalyst to afford Compound 2, which was then purified via silica gel chromatography. Compound 2 was further purified with dichloromethane and toluene via silica gel chromatography followed by crystallization with dichloromethane and MTBE. The purified Compound 2 was then purified via crystallization with ethanol and heptane to afford Compound 2. The product was then assessed using HPLC.

Materials and Methods

Step 1. Synthesis of 9-[2-( ₂ ,2-Dimethyl-propylamino)-ethyl]-8-(6- trimethylstannanyl- benzo[l,3]dioxol-5-ylsulfanyl)-9H-purin-6-ylamine ( Compound 2).

A schematic of Step 1 is shown in FIG. 2A. A 12 L glass reactor was assembled with a magnetic stirrer, condenser, thermocouple, addition funnel, and a nitrogen inlet and the apparatus was purged with nitrogen. Compound 7 (121 g), Pd ₂ (dba) ₃ (20.9 g), and toluene (2.4 L) were charged sequentially to the reactor. The reaction mixture was stirred for about 7 minutes until a suspension was formed. Nitrogen gas was bubbled through the reaction mixture for about 23 minutes. Hexamethylditin (302 g) was then charged to the reactor. The reaction mixture was heated to about 66 °C and stirred for about 41.5 hours at about 78 °C when a PCT by HPLC failed. Additional Pd2(dba)3 (20.9 g) was charged to the reactor and the reaction mixture was stirred at about 76 °C for an additional 19 hours until a PCT by HPLC passed. The reaction mixture was then cooled to about 44 °C and filtered through celite (596 g). The filter cake was washed with toluene (0.6 L) and the filtrate was collected. The filtrate was then transferred to the rotavapor and distilled under vacuum at 60 °C until distillation stopped, and the residue was weighed (382 g). A clean, dry column with nitrogen inlet was then assembled. Dichloromethane (6.0 L) and silica gel (1922 g) were charged onto the column and thoroughly mixed. The column was eluted to the upper surface of the silica gel and the eluent was collected in a clean container. Sea sand (996 g) was loaded onto the top of the column. The crude Compound 2 (382 g) and dichloromethane (0.6 L) were mixed thoroughly in a clean container until a solution was formed. The solution was carefully loaded onto the column, the container rinsed with dichloromethane (0.3 L) and the rinse charged to the column. The column was eluted with the collected eluent (1.8 L) and additional dichloromethane (3.6 L). The column was then eluted with 300:10:0.05 (v/v/v) DCM : MeOH : Et3N, prepared separately from dichloromethane (18 L), methanol (0.60 L), and triethylamine (0.030 L). The fractions were checked by TLC. The desired fractions were collected, transferred to the rotavapor, and distilled under vacuum at 44 °C until distillation stopped to afford Compound 2 (86 g).

A summary of the Compound 2 produced in step 1 is presented in Table 2 below. Table 2. Synthesis of Compound 2

Step 2. Purification of 9-[2-( ₂ ,2-Dimethyl-propylamino)-ethyl]-8-(6- trimethylstannanyl- benzo[ 1,3 ]dioxol-5-ylsulfanyl)-9H-purin-6-ylamine ( Purified Compound 2).

A schematic of Step 2 is shown in FIG. 2B. A 12 L glass reactor was assembled with a magnetic stirrer, condenser, thermocouple, addition funnel, and a nitrogen inlet and the apparatus was purged with nitrogen. Sn-PU- AD (83 g), dichloromethane (0.12 L), and toluene (1.2 L) were charged to the reactor. The reaction mixture was heated to about 91 °C and the distillate was collected (105 mL). The reaction mixture was then stirred at about 107 °C for about 5 hours. The batch was cooled to about 45 °C, transferred to the rotavapor, and distilled under vacuum at 56 °C until distillation stopped, and the residue was weighed (86 g). A clean, dry column with nitrogen inlet was then assembled. Dichloromethane (7.0 L) and silica gel (1744 g) were charged onto the column and thoroughly mixed. The column was eluted to the upper surface of the silica gel. Sea sand (999 g) was loaded onto the top of the column. Eluting solvent, 300:10:0.5 (v/v/v) DCM: MeOH: Et3N, was prepared separately from dichloromethane (17 L), methanol (0.55 L), and triethylamine (0.028 L). The crude Compound 2 (86 g) and eluting solvent (0.5 L) were mixed thoroughly in a clean container until a solution was formed. The solution was carefully loaded onto the column, the container rinsed with eluting solvent (0.3 L) and the rinse charged to the column. The column was then eluted with the remainder of the eluting solvent (16.5 L), the fractions checked by TLC. The desired fractions were collected, transferred to the rotavapor, and distilled under vacuum at 38 °C until distillation stopped, and the residue was weighed (70 g). A 12 L glass reactor was assembled with a magnetic stirrer, condenser, thermocouple, addition funnel, and a nitrogen inlet and the apparatus was purged with nitrogen. The distillation residue (70 g) and dichloromethane (0.25 L) were charged to the reactor, using dichloromethane to assist the transfer. The batch was heated to about 36°C and stirred for about 30 minutes at about 37 °C. The batch was filtered, the filter cake washed with dichloromethane (0.12 L) and the filtrate collected. The batch was then transferred to the rotavapor and distilled under vacuum at 34 °C until distillation stopped, and the residue was weighed (69 g). A 12 L glass reactor was assembled with a magnetic stirrer, condenser, thermocouple, addition funnel, and a nitrogen inlet and the apparatus was purged with nitrogen. Dichloromethane (0.8 L) was filtered through an in-line filter into a clean container. The distillation residue (69 g) and a portion of the filtered dichloromethane (0.08 L) were charged to the reactor, using dichloromethane to assist the transfer. The batch was then heated to about 39 °C. MTBE (0.83 L) was filtered through an in-line filter into a clean container. A portion of the filtered MTBE (0.21 L) was then charged to the reactor while maintaining a temperature of about 39 °C. The batch was stirred at about 38 °C for about 1 hour. The batch was cooled to about 6 °C and stirred for about 1 hour at about 6 °C. The batch was then filtered, the filter cake washed with polish filtered MTBE (0.12 L) and the filtrate collected. The filter cake was dried on a filter by pulling nitrogen for about 1 hour. The product was then transferred to drying trays and further dried under vacuum at about 40 °C for about 6.5 days to afford the purified Compound 2 (54.76 g).

A schematic of Step 3 is shown in FIG. 2C. A summary of the purified Compound 2 produced in step 2 is presented in Table 3 below.

Table 3. Purification of Compound 2

Step 3. Purification of purified 9-[2-( ₂ , 2-Dimethyl-propylamino)-ethyl]-8-(6- trimethylstannanyl-benzo[l,3]dioxol-5-ylsulfanyl)-9H-purin-6 -ylamine ( Compound 2).

A 12 L glass reactor was assembled with a magnetic stirrer, condenser, thermocouple, addition funnel, and a nitrogen inlet and the apparatus was purged with nitrogen. Ethanol (1.1 L) was filtered through an in-line filter into a clean container. Purified Compound 2 (53.23 g) and a portion of the filtered ethanol (0.85 L) were charged to the reactor. The batch was heated to about 61 °C and stirred at about 62 °C until a clear solution was obtained. Heptane (5.3 L) was then filtered through an in-line filter into a clean container. A portion of the filtered heptane (1.6 L) was charged to the reactor in small portions over about 1 hour at about 58 °C until a suspension was formed. The batch was then stirred at about 41 °C for about 1 hour. The batch was then transferred to the rotavapor and distilled under vacuum at 49 °C until the remaining volume was about 1.2 L. A portion of the filtered heptane (1.6 L) was charged to the rotavapor flask in small portions over about 18 minutes while maintaining a temperature of 49 °C. The batch was then distilled under vacuum at 45 °C until the remaining volume was about 1.2 L. A 12 L glass reactor was assembled with a magnetic stirrer, condenser, thermocouple, addition funnel, and a nitrogen inlet and the apparatus was purged with nitrogen. The distillation residue (1.2 L) and a portion of the filtered heptane (0.53 L) were charged to the reactor, using heptane to assist the transfer. The batch was cooled to about 3 °C and stirred for about 1 hour at about 4 °C. The batch was then filtered, the filter cake washed with polish filtered heptane (0.5 L) and the filtrate collected. The filter cake was dried on a filter by pulling nitrogen for about 1 hour. The product was then transferred to drying trays and further dried under vacuum at about 70 °C for about 22 hours to afford Compound 2 (52.40 g).

A summary of the Compound 2 produced in step 3 is presented in Table 4 below.

Table 4. Purification of purified Compound 2 Analytical methods included HPLC analysis using the following preparation of solutions:

1. Mobile Phase A (0.1% TFA in DI Water): Example preparation: add 1.0 mL of TFA into 1000 mL of degassed DI Water. Mix well.

2. Mobile Phase B (0.1% in MeCN): Example preparation: added 1.0 mL of TFA into 1000 mL of degassed MeCN. Mix well.

3. Diluent: Pure Methanol (MeOH).

The following calculations were used:

For Area% Purity:

Total Impurity (TI) = sum of all average percent impurities greater than or equal to the reporting threshold (0 .05%).

Report the average for each individual impurity >. 0.05% to the nearest 0.01%. Report total impurities (TI) to the nearest 0.01%.

Compound 2 purity = 100.0 - TI

Report the Compound 2 purity to the nearest 0.1%

For Assay (w/w%) of Compound 2:

Where:

A _s = Area of the Compound 2 peak in the sample injection

A _st = Average area of the Compound 2 peaks in the bracketing standard injections

C _s = Sample concentration (mg/mL; based on sample corrected for moisture and residual solvents)

C _st , = Standard concentration (mg/mL)

P = Standard purity

Results In prior studies, when Pd(PPh3)4 was used as a catalyst with Compound 6 to produce Compound 1 in a Stannylation reaction, the reaction stalled and additional charges of Pd(PPh3)4 were needed to mitigate the impact of the stalling (data not shown).

In contrast, as shown in Tables 5-6 below, reactions using Pd ₂ (dba) ₃ as a catalyst resulted in production of Compound 2 with high chemical purity. For example, the chemical purity of the product in each batch was greater than 98%. Therefore, this Example shows that Pd ₂ (dba) ₃ may be used as an efficient catalyst for production of Sn-labeled Hsp90 inhibitors. Such efficiency may be manifested by reduced stalling and/or reduced dependence on additional charges of the catalyst.

Table 5. Analysis results of a batch of Compound 2 produced using the methods described in this Example. 3 Water Content 4) 3 a: ND = Below the limit of detection (LOD). For HPLC, LOD is ~ 0.02%; For GC, LOD is 100 ppm. Table 6. Analysis results of another batch of Compound 2 produced using the methods described in this Example. a: ND = Below the limit of detection (LOO). For HPLC, LOD is -0.02%; For GC, LOD is 100 ppm. Example 2.

This Example describes production of a compound of Formula III: ents were conducted with Compound 2 as either a free base or as a hydrogen iodide salt (HI) and radioactivity of the product was assessed.

Materials and Methods

The following procedure was used in a 1 mCi reaction:

1. Charge Eppendorf with 25 μL Compound 2 as a free base or Compound 2· HI

2. Add 10 μL NaI-131

3. Add 100 μL water for injection

4. Add 25 μL 0.8 M H ₃ PO ₄

5. Add 10 μL 6.4% peracetic acid

6. Incubate 1 min at room T 7. Add 50 μL sodium metabisulfite in saturated NaHC0 ₃

8. Invert 10-mL syringe containing 8 mL water. Inject reaction solution onto top of liquid.

9. Pass through Sep-Pak to waste

10. Elute with 3 mL ethanol to product

Results

The results described below were obtained using the methods described in this example. When using Compound 2 as a free base, 595 μCi product and 30 μCi waste were detected. 7 μCi remained in the Sep-Pak, while 62 μCi remained in the reaction vial and syringe. The method resulted in an 86% recovered yield with a specific activity of 24 mCi/mg.

When using Compound 2 as a hydrogen iodide salt, 573 μCi product and 34 μCi waste were detected. 3 μCi remained in the Sep-Pak and 63 μCi remained in the reaction vial and syringe. The method resulted in an 85% recovered yield with a specific activity of 23 mCi/mg.

Example 3.

This Example describes production of a compound of Formula III: (Formula III) in which W is I ¹³¹ , using: 1) chloramine-T in which the ratio of the mass of chloramine-T to the mass of the compound of Formula III in the reaction was 3:5, and 2) Compound 2: (Compound 2) as a substrate. Experiments were conducted with Compound 2 as a free base and radioactivity of the product was assessed.

Experiment 1

Materials and Methods

The following methods and materials were used in Experiment 1:

1. Combine 25 μL 1 mg/mL Compound 2 free base (in ethanol), 10 μL Nal- 131 (—3-3.5 mCi) in 0.01 M NaOH, 10 μL 1.5 mg/mL chloramine-T, and 10 μL 1 M phosphate buffer pH 7;

2. Incubate at ambient temperature for 5 minutes;

3. Push incubated reaction through Sep-Pak with 10 mL DI water to waste; and

4. Elute product with 3 mL ethanol.

Results

Table 7 shows the results when eluting the product in a single 3 mL fraction. Excluding the activity in the syringe and vial, which didn't get transferred to the Sep-Pak, conversion to product was 3270/3321 = 98.5%.

Table 7. Results of Experiment 1 Experiment 2

Materials and Methods For experiment 2, the same methods and materials were used as in Experiment 1, except in step (4), three, 1-mL ethanol fractions were removed, rather than a single 3-mL fraction. Results

Table 8 shows the results when eluting with three, 1-mL ethanol fractions. Total product conversion was 3118/3173 = 98.3%. Of the product, 89.5% was in the first mL fraction, 9.4% in the second fraction, and 1.1% in the third fraction. The results suggest that the elution volume may be reduced to 2 mL or even 1.5 ml. Without being bound by a particular theory, less ethanol in the product may be desirable as the product may have to be diluted with less buffer when formulating an injectable product. The maximum allowable ethanol in injectable products is often 10%.

Table 8. Results of Experiment 2

Experiment 3

Materials and Methods

For experiment 3, a pre-mixed solution of Compound 2 free base and chloramine-T in acetic acid were tested. A solution of 1 mg/mL Sn-PUAD and 0.6 mg/mL chloramine-T in acetic acid was prepared, so that 25 μL of the solution would contain the appropriate amounts of both reagents. 25 μL of the mixed solution, 10 μL of NaI-131, and 10 μL of P04 buffer were combined. Incubation ran ~ 7.5 minutes. The full 3 mL ethanol was used to elute the product. Results

Table 9 shows the results with pre-mixed Compound 2 free base and chloramine-T in acetic acid. Recovery was comparable to experiments using unmixed Compound 2 free base and chloramine-T. Recover was 3290/3380 = 97.3% in this experiment.

Table 9. Results of Experiment 3

Experiment 4

Materials and Methods

For experiment 4, a refrigerated pre-mixed solution comprising Compound 2, chloramine-T and acetic acid was tested. The solution from Experiment 3 was incubated overnight and used the next day (about 17 hours later). The acetic in the solution froze during the refrigeration and was thawed prior to use. The methods described in Experiment 3 were used.

Results As shown in Table 10, overnight refrigeration of the pre-mixed solution comprising

Compound 2, chloramine-T and acetic acid did not significantly affect the recovered yield, suggesting a pre-mixed solution comprising Compound 2 is stable when refrigerated overnight. Recovery was 3050/3104 = 98.3% Table 10. Results of Experiment 4

Example 4.

This Example describes production of a compound of Formula III: (Formula III) in which W is I ¹³¹ , using 1) chloramine-T in which the ratio of the mass of chloramine-T to the mass of the compound of Formula III in the reaction was 3:5, and 2) Compound 2: (Compound 2) free base as a substrate, using the device shown in FIG. 3. Radioactivity of the product was assessed.

Materials and Methods

Experiment 1

The device in FIG. 3 was used and the following protocol was used in Experiment 1:

1. In FIG. 3, R is the source vial. Inject pre-mixed Sn-PU-AD, chloramine-T and Buffer (not shown). The pre-mixed solution was prepared as indicated in Example 3, Experiment 4 above. 2-mL vial was used and injected a mixture of 25 μl Compound 2, chloramine-T, and Acetic acid, 10 μL NaI-131, and 100 μL 0.1 M PO ₄ buffer. (A greater volume of diluted PO ₄ buffer was used to ensure all mixture would transfer by a 0.3-mL syringe.)

2. Fill S 1 with 10 mL H ₂ O, 10 mL air, flush reaction mixture from R through SP (SCI in proper orientation); SC3 oriented to deliver to W.

3. Reverse SCI and SC3 orientations, orient SC2 to deliver 3 mL EtOH from S3 through SP and 0.2 pm filter to P.

4. Reverse SC2 orientation to deliver make-up water (i.e., water to bring the solution to a particular volume and/or concentration) or buffer from S2 through SP and filter to P. a. In this experiment, air in S2 was used to push all Product through without use of a filter

Results Table 11 shows the results of this experiment. Notably, product conversion was 2850/2891 = 98.6%. Even including losses in the system, the total recovery was 2850/2974 = 95.8%. Therefore, Compound 2 was produced with a high yield using the device in FIG. 3 and the methods described in this example.

Table 11. Results using the device in FIG. 3

Experiment 2

Materials and Methods The device in FIG. 3 was used with re-thawed solution comprising Compound 2, chloramine-T, and acetic acid that was refrigerated for 6 days. The materials and methods are otherwise the same as indicated in Experiment 1 of this Example.

Results

Table 12 shows the results that were obtained using the re-thawed solution that was refrigerated for six days. Excluding the amounts left in the vial and device, the conversion was 33.1%, with 62.2% in Waste and 4.7% in the Sep-Pak.

Decomposition of Compound 2 did occur in the frozen acetic acid over the course of six days as compared to the results with one day of refrigeration (Experiment 1 of this Example). However, despite the decomposition, 33% recovery was achieved.

Table 12. Results using the device in FIG.3 along with refrigerated pre-mixed reagents. Experiment 3

Materials and Methods The device in FIG. 3 was used with the reagents: 25 μL 1 mg/mL Compound 2, 10 μL NaI-131, 10 μL 1.5 mg/mL chloramine-T, 10 μL 1 M PO4 buffer, 3 mL EtOH elution). Compound 2 was stored in ethanol and was refrigerated for 6 days. Results

Table 13 shows the results using Compound 2 stored in ethanol. The conversion was 98.6%. Therefore, this Experiment demonstrates that Compound 2 is stable in ethanol at 2-8 °C for about a week at minimum. Table 13. Results using the device in FIG.3 along with Compound 2 stored in ethanol.

Experiment 4

Materials and Methods The materials and methods were the same as in Experiment 3 of this Example, but 3 mL 50% ethanol (in water) was used for elution.

Results

As shown in Table 14, elution in 50% ethanol resulted in a recovery of 80.3%. These results suggest that elution in pure ethanol may result in a higher recovery rate than in diluted ethanol.

Table 14. Results using the device in FIG.3 along with elution in 50% ethanol.

Example 5.

This example describes production of a compound of Formula III: (Formula III) in which W is I ¹²⁴ , using: 1) chloramine-T in which the ratio of the mass of chloramine-T to the mass of the compound of Formula III in the reaction was 3:5, and 2) Compound 2: (Compound 2) free base as a substrate, using the device shown in FIG. 3. Experiments were conducted with Compound 2 as a free base and using the device shown in FIG. 3. Radioactivity of the product is assessed.

Materials and Methods

The device of FIG. 3 is used with all vials (and the Sep-Pak) shielded. Reaction vial ® is source 1-124 vial. The following protocol is used:

1. Inject pre-mixed Sn-PU-AD, Chloramine-T and Buffer (not shown).

2. With SI, push reaction mixture from RV to SP (SCI in proper orientation)

3. Remove SI, fill with 10 mL H2O, 10 mL air, reattach.

4. Flush RV and SP with contents of SI (H20 first, then air); SC3 oriented to deliver to W. 5. Reverse SCI and SC3 orientations, orient SC2 to deliver 3 mL EtOH, 5 mL air from S3 (through SP and 0.2u filter to P).

6. Reverse SC2 orientation to deliver makeup water or buffer through SP and filter to P. Radioactivity is assessed.

Aspects and Embodiments

Various aspects and embodiments provided by this disclosure are listed below. Clause 1. A method of producing a compound of Formula II: (Formula II) or a pharmaceutically acceptable salt thereof, comprising reacting: a compound of Formula I: (Formula I) or a pharmaceutically acceptable salt thereof with a radioiodine salt in the presence of peracetic acid in a solution at a pH between 2-5, thereby forming a reaction mixture, wherein:

W is a radioiodine; X is — C¾ — , — O — , or — S — ;

Y ¹ and Y ² are independently =CR ^3a — or =N — , as valency permits;

Z ¹ , Z ² , and Z ³ are independently — CH= or — N=, as valency permits;

R ¹ is hydrogen or halogen; L is a straight or branched, C _2-14 aliphatic group wherein one or more carbons are optionally and independently replaced by -Cy-, — N(R)C(O) — , — C(O)N(R) — , —

C(O)N(O) — , — N(R)SO _2— , — SO ₂ N(R)— , — O— , — C(O)— , — OC(O)— , — C(O)O— , — S — , — SO — , or — SO ₂ — , or wherein one or more carbons are independently replaced by — NR — , wherein R is not a -Boc protecting group in L; each -Cy- is independently an optionally substituted 3-8 membered bivalent, saturated, partially unsaturated, aryl ring, or heteroaryl ring having 1-4 heteroatoms independently selected from nitrogen, oxygen, or sulfur, or an optionally substituted 8-10 membered bivalent saturated, partially unsaturated, aryl bicyclic ring, or heteroaryl bicyclic ring having 1-5 heteroatoms independently selected from nitrogen, oxygen, or sulfur;

R ² is hydrogen or an optionally substituted group selected from the group consisting of C _1-6 aliphatic, phenyl, 3- to 7-membered saturated or partially unsaturated monocyclic carbocyclyl, 3- to 7-membered saturated or partially unsaturated monocyclic heterocyclyl having 1-2 heteroatoms selected from oxygen, nitrogen, or sulfur, 5- to 6-membered heteroaryl having 1-4 heteroatoms selected from oxygen, nitrogen, or sulfur, 7- to 10- membered saturated or partially unsaturated bicyclic carbocyclyl, 7- to 10-membered saturated or partially unsaturated bicyclic heterocyclyl having 1-4 heteroatoms selected from oxygen, nitrogen, or sulfur, 7- to 10-membered bicyclic heteroaryl having 1-4 heteroatoms selected from oxygen, nitrogen, or sulfur, or 8- to 10-membered bicyclic aryl; each R ³ is independently halogen, — NO ₂ , — CN, — OR, — SR, — N(R) ₂ , — C(O)R,

— CO ₂ R, — C(O)C(O)R, — C(O)CH ₂ C(O)R, — S(O)R, — S(O) ₂ R, — C(O)N(R) ₂ , — SO ₂ N(R) ₂ , — OC(O)R, — N(R)C(O)R, — N(R)N(R) ₂ , or optionally substituted C _1-6 aliphatic or pyrrolyl; or two R ³ groups are taken together with their intervening atoms to form Ring A, wherein Ring A is an optionally substituted 3- to 7-membered partially unsaturated carbocyclyl, optionally substituted phenyl, an optionally substituted 5- to 6-membered partially unsaturated monocyclic heterocyclyl having 1-2 heteroatoms selected from oxygen, nitrogen, or sulfur; or an optionally substituted 5- to 6-membered heteroaryl having 1-4 heteroatoms selected from oxygen, nitrogen, or sulfur, or 6-membered aryl;

R ^3a is R ³ or hydrogen;

R ⁴ is C _1-4 alkyl; each R is independently hydrogen or an optionally substituted group selected from C _{1- 6} aliphatic, phenyl, 3- to 7-membered saturated or partially unsaturated carbocyclyl, 3- to 7- membered saturated or partially unsaturated monocyclic heterocyclyl having 1-2 heteroatoms selected from oxygen, nitrogen, or sulfur, or 5- to 6-membered heteroaryl having 1-4 heteroatoms selected from oxygen, nitrogen, or sulfur, or: two R groups on the same nitrogen are taken together with their intervening atoms to form an optionally substituted ring selected from 3- to 7-membered saturated or partially unsaturated monocyclic heterocyclyl having 1-2 heteroatoms selected from oxygen, nitrogen, or sulfur, or 5- to 6-membered heteroaryl having 1-4 heteroatoms selected from oxygen, nitrogen, or sulfur, thereby producing a compound of Formula II or a pharmaceutically acceptable salt thereof.

Clause 2. The method of clause 1, wherein the compound of Formula II or the pharmaceutically acceptable salt thereof is a compound of Formula III or a pharmaceutically acceptable salt thereof, or Formula IV or a pharmaceutically acceptable salt thereof: (Formula III) or a pharmaceutically acceptable salt thereof; or

(Formula IV) or a pharmaceutically acceptable salt thereof. Clause 3. The method of any one of clauses 1-2, wherein the compound of Formula I or the pharmaceutically acceptable salt thereof comprises Compound 1 or a pharmaceutically acceptable salt thereof or Compound 2 or a pharmaceutically acceptable salt thereof: (Compound 2) or a pharmaceutically acceptable salt (Compound 1) or a pharmaceutically acceptable salt thereof.

Clause 4. The method of any one of clauses 1-3, wherein the compound of Formula I is provided as a free base or as a hydrogen iodide salt (HI).

Clause 5. The method of any one of clauses 1-4, wherein the compound of Formula I or the pharmaceutically acceptable salt thereof is reacted with a radioiodine sodium salt.

Clause 6. The method of any one of clauses 1-5, wherein the compound of Formula I is provided as a free base. Clause 7. The method of any one of clauses 1-6, wherein the radioiodine or salt thereof is selected from I ¹²³ , I ¹²⁴ , or I ¹³¹ or a salt thereof.

Clause 8. The method of any one of clauses 1-7, wherein the compound of Formula II or a pharmaceutically acceptable salt thereof and/or the compound of Formula I or the pharmaceutically acceptable salt thereof is a good manufacturing practices (GMP) grade compound.

Clause 9. The method of any one of clauses 1-8, wherein the solution comprises about 0.1 to about 1 M phosphoric acid (H ₃ PO ₄ ) or sulfuric acid and water and the reaction occurs between about 15 to about 30 °C for about 0.5 to about 1.5 minutes, optionally about 1 minute.

Clause 10. The method of clause 9, wherein the solution comprises about 0.8 M phosphoric acid (H ₃ PO ₄ ) and water.

Clause 11. The method of clause 10, wherein the reaction occurs between about 20 °C to about 30 °C for about 0.5 to about 1.5 minutes, optionally about 1 minute.

Clause 12. The method of any one of clauses 1-11, wherein the method further comprises adding, to the reaction mixture, sodium metabisulfite in saturated sodium bicarbonate (NaHCO ₃ ) following the reaction.

Clause 13. The method of any one of clauses 1-12, wherein the peracetic acid is about 3% to about 10% peracetic acid.

Clause 14. The method of clause 13, wherein the peracetic acid is about 6% to about 7% peracetic acid, optionally about 6.3%, about 6.4% or about 6.5% peracetic acid.

Clause 15. The method of any one of clauses 1-14, further comprising purifying the compound of Formula II or a pharmaceutically acceptable salt thereof from the reaction mixture. Clause 16. The method of any one of clauses 1-15, wherein the compound of Formula II or a pharmaceutically acceptable salt thereof is recovered at about 80%, about 85%, about 90%, or about 95% yield. Clause 17. The method of any one of clauses 1-16, wherein the specific activity of the compound of Formula II or a pharmaceutically acceptable salt thereof is at least 10 mCi/mg, at least 20 mCi/mg, at least 30 mCi/mg, or at least 40 mCi/mg.

Clause 18. A method of producing a compound of Formula II: (Formula II) or a pharmaceutically acceptable salt thereof, comprising reacting:

(a) a compound of Formula I: (Formula I) or a pharmaceutically acceptable salt thereof;

(b) chloramine-T; and

(c) a radioiodine salt, wherein the ratio of the mass of chloramine-T to the mass of the compound of Formula I or the pharmaceutically acceptable salt thereof in the reaction is about 3 to about 5, thereby forming a reaction mixture, wherein:

W is a radioiodine;

X is — CH ₂ — , — O— , or — S— ; Y 1 and Y2 are independently =CR3a — or =N — , as valency permits;

Zl, Z2, and Z3 are independently — CH= or — N=, as valency permits;

R ¹ is hydrogen or halogen;

L is a straight or branched, C _2-14 aliphatic group wherein one or more carbons are optionally and independently replaced by -Cy-, — N(R)C(O) — , — C(O)N(R) — , — C(O)N(O) — , — N(R)SO _2— , — SO ₂ N(R)— , — O— , — C(O)— , — OC(O)— , — C(O)O— , — S — , — SO — , or — SO ₂ — , or wherein one or more carbons are independently replaced by — NR — , wherein R is not a -Boc protecting group in L; each -Cy- is independently an optionally substituted 3-8 membered bivalent, saturated, partially unsaturated, aryl ring, or heteroaryl ring having 1-4 heteroatoms independently selected from nitrogen, oxygen, or sulfur, or an optionally substituted 8-10 membered bivalent saturated, partially unsaturated, aryl bicyclic ring, or heteroaryl bicyclic ring having 1-5 heteroatoms independently selected from nitrogen, oxygen, or sulfur;

R ² is hydrogen or an optionally substituted group selected from the group consisting of C _1-6 aliphatic, phenyl, 3- to 7-membered saturated or partially unsaturated monocyclic carbocyclyl, 3- to 7-membered saturated or partially unsaturated monocyclic heterocyclyl having 1-2 heteroatoms selected from oxygen, nitrogen, or sulfur, 5- to 6-membered heteroaryl having 1-4 heteroatoms selected from oxygen, nitrogen, or sulfur, 7- to 10- membered saturated or partially unsaturated bicyclic carbocyclyl, 7- to 10-membered saturated or partially unsaturated bicyclic heterocyclyl having 1-4 heteroatoms selected from oxygen, nitrogen, or sulfur, 7- to 10-membered bicyclic heteroaryl having 1-4 heteroatoms selected from oxygen, nitrogen, or sulfur, or 8- to 10-membered bicyclic aryl; each R ³ is independently halogen, — NO ₂ , — CN, — OR, — SR, — N(R) ₂ , — C(O)R, — CO ₂ R, — C(O)C(O)R, — C(O)CH ₂ C(O)R, — S(O)R, — S(O) ₂ R, — C(O)N(R) ₂ , — SO ₂ N(R) ₂ , — OC(O)R, — N(R)C(O)R, — N(R)N(R) ₂ , or optionally substituted C _1-6 aliphatic or pyrrolyl; or two R ³ groups are taken together with their intervening atoms to form Ring A, wherein Ring A is an optionally substituted 3- to 7-membered partially unsaturated carbocyclyl, optionally substituted phenyl, an optionally substituted 5- to 6-membered partially unsaturated monocyclic heterocyclyl having 1-2 heteroatoms selected from oxygen, nitrogen, or sulfur; or an optionally substituted 5- to 6-membered heteroaryl having 1-4 heteroatoms selected from oxygen, nitrogen, or sulfur, or 6-membered aryl;

R ^3a is R ³ or hydrogen;

R ⁴ is C _1-4 alkyl; each R is independently hydrogen or an optionally substituted group selected from C _{1- 6} aliphatic, phenyl, 3- to 7-membered saturated or partially unsaturated carbocyclyl, 3- to 7- membered saturated or partially unsaturated monocyclic heterocyclyl having 1-2 heteroatoms selected from oxygen, nitrogen, or sulfur, or 5- to 6-membered heteroaryl having 1-4 heteroatoms selected from oxygen, nitrogen, or sulfur, or: two R groups on the same nitrogen are taken together with their intervening atoms to form an optionally substituted ring selected from 3- to 7-membered saturated or partially unsaturated monocyclic heterocyclyl having 1-2 heteroatoms selected from oxygen, nitrogen, or sulfur, or 5- to 6-membered heteroaryl having 1-4 heteroatoms selected from oxygen, nitrogen, or sulfur, thereby producing a compound of Formula II or a pharmaceutically acceptable salt thereof.

Clause 19. The method of clause 18, wherein the compound of Formula II or the pharmaceutically acceptable salt thereof is a compound of (Formula III) or a pharmaceutically acceptable salt thereof; or a compound of

(Formula IV) or a pharmaceutically acceptable salt thereof.

Clause 20. The method of any one of clauses 18-19, wherein the compound of Formula I or the pharmaceutically acceptable salt thereof comprises: (Compound 2) or a pharmaceutically acceptable salt thereof; or

(Compound 1) or a pharmaceutically acceptable salt thereof. Clause 21. The method of any one of clauses 18-20, wherein the compound of Formula I is provided as a free base.

Clause 22. The method of any one of clauses 18-21, wherein the compound of Formula I or the pharmaceutically acceptable salt thereof is reacted with a radioiodine sodium salt.

Clause 23. The method of any one of clauses 18-22, wherein the reaction further comprises phosphate buffer at about pH 7.

Clause 24. The method of any one of clauses 18-23, the radioiodine or salt thereof is I ¹²³ , I ¹²⁴ , or I ¹³¹ or a salt thereof.

Clause 25. The method of any one of clauses 18-24, wherein the compound of Formula II or a pharmaceutically acceptable salt thereof and/or the compound of Formula I or the pharmaceutically acceptable salt thereof and is a good manufacturing practices (GMP) grade compound.

Clause 26. The method of any one of clauses 18-25, wherein the yield of the compound of Formula II or the pharmaceutically acceptable salt thereof is at least 80%.

Clause 27. The method of any one of clauses 18-26, wherein the compound of Formula I or the pharmaceutically acceptable salt thereof is provided in ethanol.

Clause 28. The method of any one of clauses 18-27, wherein the compound of Formula I or the pharmaceutically acceptable salt thereof and chloramine-T are provided in a pre-mixed solution in acetic acid.

Clause 29. The method of any one of clauses 18-28, further comprising passing the reaction mixture through a Sep-Pak and eluting the compound of Formula II with less than 3 mL of pure ethanol.

Clause 30. The method of any one of clauses 18-29, wherein the radioiodine salt is provided in about 0.01M NaOH. Clause 31. The method of any one of clauses 18-30, wherein the amount of radioiodine salt is between about 3 and about 3.5 mCi.

Clause 32. A method of producing a compound of Formula I: (Formula I) or a pharmaceutically acceptable salt thereof, comprising reacting in a reaction mixture: a compound of Formula V: (Formula V) or a pharmaceutically acceptable salt thereof with hexamethylditin (Sn ₂ Me ₆ ) and tris(dibenzylideneacetone)dipalladium(0) (Pd ₂ (dba) ₃ ) in a solution, thereby producing a compound of Formula I or a pharmaceutically acceptable salt thereof.

Clause 33. The method of clause 32, the reaction occurs between about 60 °C and about 80 °C.

Clause 34. The method of any one of clauses clause 32-33, further comprising purifying the compound of Formula I. Clause 35. The method of clause 34, wherein purifying the purifying the compound of Formula I comprises mixing the compound of Formula I with dichloromethane (DCM) and stirring the mixture to form a substantially clear solution. Clause 36. The method of clause 35, further comprising adding purified water to the substantially clear solution, stirring the solution for at least 5 minutes, and allowing the solution to separate into an organic layer and an aqueous layer. Clause 37. The method of clause 36, further comprising adding purified water, mixing the layers for at least 15 minutes, and allowing the layers to separate, optionally further adding purified water, mixing the layers for at least 15 minutes, and allowing the layers to separate.

Clause 38. The method of any one of clauses 36-37, further comprising filtering the organic layer, washing the reaction vessel with DCM, and concentrating the filtrate and the wash.

Clause 39. The method of clause 38, wherein the concentrating occurs at no more than 50 °C to distill the compound of Formula I.

Clause 40. The method of clause 39, wherein the compound of Formula I is further dried under vacuum at no more than 70 °C.

Clause 41. The method of any one of clauses 32-40, wherein the compound of Formula V or the pharmaceutically acceptable salt thereof and/or the compound of Formula I or the pharmaceutically acceptable salt thereof is a good manufacturing practices (GMP) grade compound.

Clause 42. The method of any one of clauses 32-41, wherein the method further comprises adding ethanol (EtOH) -Heptane to the compound of Formula I.

Clause 43. The method of any one of clauses 32-42, wherein the compound of Formula I or the pharmaceutically acceptable salt thereof comprises :

(Compound 2) or a pharmaceutically acceptable salt

(Compound 1) or a pharmaceutically acceptable salt thereof.

Clause 44. The method of any one of clauses 32-43, wherein the compound of Formula V or the pharmaceutically acceptable salt thereof comprises:

Compound 6: or a pharmaceutically acceptable salt thereof; or Compound 7 : pharmaceutically acceptable salt thereof.

Clause 45. A kit comprising:

(i) a compound of Formula I: (Formula I) or a pharmaceutically acceptable salt thereof;

(ii) phosphoric acid (H ₃ PO ₄ ); and

(iii) peracetic acid, wherein:

X is — CH _2— , — O— , or — S— ;

Y ¹ and Y ² are independently =CR ^3a — or =N — , as valency permits;

Z ¹ , Z ² , and Z ³ are independently — CH= or — N=, as valency permits;

R ¹ is hydrogen or halogen;

L is a straight or branched, C2-14 aliphatic group wherein one or more carbons are optionally and independently replaced by -Cy-, — N(R)C(O) — , — C(O)N(R) — , — C(O)N(O) — , — N(R)SO _2— , — SO ₂ N(R)— , — O— , — C(O)— , — OC(O)— , — C(O)O— , — S — , — SO — , or — SO _{2 —} , or wherein one or more carbons are independently replaced by — NR — , wherein R is not a -Boc protecting group in L; each -Cy- is independently an optionally substituted 3-8 membered bivalent, saturated, partially unsaturated, aryl ring, or heteroaryl ring having 1-4 heteroatoms independently selected from nitrogen, oxygen, or sulfur, or an optionally substituted 8-10 membered bivalent saturated, partially unsaturated, aryl bicyclic ring, or heteroaryl bicyclic ring having 1-5 heteroatoms independently selected from nitrogen, oxygen, or sulfur;

R ² is hydrogen or an optionally substituted group selected from the group consisting of C _1-6 aliphatic, phenyl, 3- to 7-membered saturated or partially unsaturated monocyclic carbocyclyl, 3- to 7-membered saturated or partially unsaturated monocyclic heterocyclyl having 1-2 heteroatoms selected from oxygen, nitrogen, or sulfur, 5- to 6-membered heteroaryl having 1-4 heteroatoms selected from oxygen, nitrogen, or sulfur, 7- to 10- membered saturated or partially unsaturated bicyclic carbocyclyl, 7- to 10-membered saturated or partially unsaturated bicyclic heterocyclyl having 1-4 heteroatoms selected from oxygen, nitrogen, or sulfur, 7- to 10-membered bicyclic heteroaryl having 1-4 heteroatoms selected from oxygen, nitrogen, or sulfur, or 8- to 10-membered bicyclic aryl; each R ³ is independently halogen, — NO ₂ , — CN, — OR, — SR, — N(R) ₂ , — C(O)R,

— CO ₂ R, — C(O)C(O)R, — C(O)CH ₂ C(O)R, — S(O)R, — S(O) ₂ R, — C(O)N(R) ₂ , — SO ₂ N(R) ₂ , — OC(O)R, — N(R)C(O)R, — N(R)N(R) ₂ , or optionally substituted C _1-6 aliphatic or pyrrolyl; or two R ³ groups are taken together with their intervening atoms to form Ring A, wherein Ring A is an optionally substituted 3- to 7-membered partially unsaturated carbocyclyl, optionally substituted phenyl, an optionally substituted 5- to 6-membered partially unsaturated monocyclic heterocyclyl having 1-2 heteroatoms selected from oxygen, nitrogen, or sulfur; or an optionally substituted 5- to 6-membered heteroaryl having 1-4 heteroatoms selected from oxygen, nitrogen, or sulfur, or 6-membered aryl;

R ^3a is R ³ or hydrogen;

R ⁴ is C _1-4 alkyl; each R is independently hydrogen or an optionally substituted group selected from C _{1- 6} aliphatic, phenyl, 3- to 7-membered saturated or partially unsaturated carbocyclyl, 3- to 7- membered saturated or partially unsaturated monocyclic heterocyclyl having 1-2 heteroatoms selected from oxygen, nitrogen, or sulfur, or 5- to 6-membered heteroaryl having 1-4 heteroatoms selected from oxygen, nitrogen, or sulfur, or: two R groups on the same nitrogen are taken together with their intervening atoms to form an optionally substituted ring selected from 3- to 7-membered saturated or partially unsaturated monocyclic heterocyclyl having 1-2 heteroatoms selected from oxygen, nitrogen, or sulfur, or 5- to 6-membered heteroaryl having 1-4 heteroatoms selected from oxygen, nitrogen, or sulfur.

Clause 46. The kit of clause 45, wherein the compound in (i) comprises: (Compound 2) or a pharmaceutically acceptable salt thereof; or

(Compound 1) or a pharmaceutically acceptable salt thereof.

Clause 47. The kit of any one of clauses 45-46, further comprising a radioiodine salt.

Clause 48. The kit of clause 47, wherein the radioiodine salt is sodium radioiodine.

Clause 49. The kit of any one of clauses 45-48, wherein the kit further comprises (iv) about 0.1 to about 1 M phosphoric acid (H ₃ PO ₄ ). Clause 50. The kit of clause 49, wherein the kit further comprises (iv) about 0.8 M phosphoric acid (H ₃ PO ₄ ).

Clause 51. The kit of any one of clauses 45-50, wherein the kit further comprises sodium metabisulfite in saturated sodium bicarbonate (NaHCO ₃ )·

Clause 52. The kit of any one of clauses 45-51, wherein the peracetic acid is about 3% to about 10% peracetic acid. Clause 53. The kit of clause 52, wherein the peracetic acid is about 6% to about 7% peracetic acid, optionally about 6.3%, about 6.4% or about 6.5% peracetic acid.

Clause 54. The kit of any one of clauses 45-53, further comprising a syringe, Sep-Pak, and/or ethanol.

Clause 55. The kit of any one of clauses 47-54, wherein the radioiodine salt is a salt of I ¹²³ , I ¹²⁴ , or I ¹³¹ .

Clause 56. A kit comprising:

(i) a compound of Formula (Formula I) or a pharmaceutically acceptable salt thereof; and

(ii) chloramine-T, wherein the ratio of the mass of chloramine-T to the mass of the compound of Formula I or the pharmaceutically acceptable salt thereof in the reaction is about 3 to about 5 and wherein:

X is — CH _2— , — O— , or — S— ;

Y ¹ and Y ² are independently =CR ^3a — or =N — , as valency permits;

Z ¹ , Z ² , and Z ³ are independently — CH= or — N=, as valency permits; R ¹ is hydrogen or halogen;

L is a straight or branched, C2-14 aliphatic group wherein one or more carbons are optionally and independently replaced by -Cy-, — N(R)C(O) — , — C(O)N(R) — , —

C(O)N(O) — , — N(R)SO _2— , — SO ₂ N(R)— , — O— , — C(O)— , — OC(O)— , — C(O)O— , — S — , — SO — , or — SO ₂ — , or wherein one or more carbons are independently replaced by — NR — , wherein R is not a -Boc protecting group in L; each -Cy- is independently an optionally substituted 3-8 membered bivalent, saturated, partially unsaturated, aryl ring, or heteroaryl ring having 1-4 heteroatoms independently selected from nitrogen, oxygen, or sulfur, or an optionally substituted 8-10 membered bivalent saturated, partially unsaturated, aryl bicyclic ring, or heteroaryl bicyclic ring having 1-5 heteroatoms independently selected from nitrogen, oxygen, or sulfur;

R ² is hydrogen or an optionally substituted group selected from the group consisting of C _1-6 aliphatic, phenyl, 3- to 7-membered saturated or partially unsaturated monocyclic carbocyclyl, 3- to 7-membered saturated or partially unsaturated monocyclic heterocyclyl having 1-2 heteroatoms selected from oxygen, nitrogen, or sulfur, 5- to 6-membered heteroaryl having 1-4 heteroatoms selected from oxygen, nitrogen, or sulfur, 7- to 10- membered saturated or partially unsaturated bicyclic carbocyclyl, 7- to 10-membered saturated or partially unsaturated bicyclic heterocyclyl having 1-4 heteroatoms selected from oxygen, nitrogen, or sulfur, 7- to 10-membered bicyclic heteroaryl having 1-4 heteroatoms selected from oxygen, nitrogen, or sulfur, or 8- to 10-membered bicyclic aryl; each R ³ is independently halogen, — NO ₂ , — CN, — OR, — SR, — N(R) ₂ , — C(O)R,

— CO ₂ R, — C(O)C(O)R, — C(O)CH ₂ C(O)R, — S(O)R, — S(O) ₂ R, — C(O)N(R) ₂ , — SO ₂ N(R) ₂ , — OC(O)R, — N(R)C(O)R, — N(R)N(R) ₂ , or optionally substituted C _1-6 aliphatic or pyrrolyl; or two R ³ groups are taken together with their intervening atoms to form Ring A, wherein Ring A is an optionally substituted 3- to 7-membered partially unsaturated carbocyclyl, optionally substituted phenyl, an optionally substituted 5- to 6-membered partially unsaturated monocyclic heterocyclyl having 1-2 heteroatoms selected from oxygen, nitrogen, or sulfur; or an optionally substituted 5- to 6-membered heteroaryl having 1-4 heteroatoms selected from oxygen, nitrogen, or sulfur, or 6-membered aryl;

R ^3a is R ³ or hydrogen;

R ⁴ is C _1-4 alkyl; each R is independently hydrogen or an optionally substituted group selected from C _{1- 6} aliphatic, phenyl, 3- to 7-membered saturated or partially unsaturated carbocyclyl, 3- to 7- membered saturated or partially unsaturated monocyclic heterocyclyl having 1-2 heteroatoms selected from oxygen, nitrogen, or sulfur, or 5- to 6-membered heteroaryl having 1-4 heteroatoms selected from oxygen, nitrogen, or sulfur, or: two R groups on the same nitrogen are taken together with their intervening atoms to form an optionally substituted ring selected from 3- to 7-membered saturated or partially unsaturated monocyclic heterocyclyl having 1-2 heteroatoms selected from oxygen, nitrogen, or sulfur, or 5- to 6-membered heteroaryl having 1-4 heteroatoms selected from oxygen, nitrogen, or sulfur Clause 57. The kit of clause 56, further comprising phosphate buffer at about pH 7.

Clause 58. The kit of clause 56 or 57, wherein the compound of Formula I or the pharmaceutically acceptable salt thereof and chloramine-T are provided in a single container. Clause 59. The kit of clause 58, wherein the container comprising the compound of

Formula I or the pharmaceutically acceptable salt thereof and chloramine-T further comprises acetic acid.

Clause 60. The kit of clause 56 or 57, wherein the compound of Formula I or the pharmaceutically acceptable salt thereof and chloramine-T are provided in separate containers.

Clause 61. The kit of clause 60, wherein the compound of Formula I or the pharmaceutically acceptable salt thereof is provided in ethanol.

Clause 62. The kit of any one of clauses 56-61, further comprising: i) ethanol; ii) water; ill) a reaction container; iv) a waste container; v) a product container; vi) a Sep-Pak; vii) one or more syringes; and/or viii) one or more stopcocks. Clause 63. The kit of any one of clauses 56-62, wherein the kit further comprises a radioiodine salt.

Clause 64. The kit of clause 63, wherein the radioiodine salt is sodium radioiodine.

Clause 65. The kit of clause 63-64, wherein the radioiodine or salt thereof is I ¹²³ , I ¹²⁴ , or

I ¹³¹ or a salt thereof.

OTHER EMBODIMENTS AND EQUIVALENTS

While several inventive embodiments have been described and illustrated herein, those of ordinary skill in the art will readily envision a variety of other means and/or structures for performing the function and/or obtaining the results and/or one or more of the advantages described herein, and each of such variations and/or modifications is deemed to be within the scope of the inventive embodiments described herein. More generally, those skilled in the art will readily appreciate that all parameters, dimensions, materials, and configurations described herein are meant to be exemplary and that the actual parameters, dimensions, materials, and/or configurations will depend upon the specific application or applications for which the inventive teachings is/are used. Those skilled in the art will recognize, or be able to ascertain using no more than routine experimentation, many equivalents to the specific inventive embodiments described herein. It is, therefore, to be understood that the foregoing embodiments are presented by way of example only and that, within the scope of the appended claims and equivalents thereto, inventive embodiments may be practiced otherwise than as specifically described and claimed. Inventive embodiments of the present disclosure are directed to each individual feature, system, article, material, kit, and/or method described herein. In addition, any combination of two or more such features, systems, articles, materials, kits, and/or methods, if such features, systems, articles, materials, kits, and/or methods are not mutually inconsistent, is included within the inventive scope of the present disclosure.

All definitions, as defined and used herein, should be understood to control over dictionary definitions, definitions in documents incorporated by reference, and/or ordinary meanings of the defined terms. All references, patents and patent applications disclosed herein are incorporated by reference with respect to the subject matter for which each is cited, which in some cases may encompass the entirety of the document.

The indefinite articles "a" and "an," as used herein in the specification and in the claims, unless clearly indicated to the contrary, should be understood to mean "at least one."

The phrase "and/or," as used herein in the specification and in the claims, should be understood to mean "either or both" of the elements so conjoined, i.e., elements that are conjunctively present in some cases and disjunctively present in other cases. Multiple elements listed with "and/or" should be construed in the same fashion, i.e., "one or more" of the elements so conjoined. Other elements may optionally be present other than the elements specifically identified by the "and/or" clause, whether related or unrelated to those elements specifically identified. Thus, as a non-limiting example, a reference to "A and/or B", when used in conjunction with open-ended language such as "comprising" can refer, in one embodiment, to A only (optionally including elements other than B); in another embodiment, to B only (optionally including elements other than A); in yet another embodiment, to both A and B (optionally including other elements); etc.

As used herein in the specification and in the claims, "or" should be understood to have the same meaning as "and/or" as defined above. For example, when separating items in a list, "or" or "and/or" shall be interpreted as being inclusive, i.e., the inclusion of at least one, but also including more than one, of a number or list of elements, and, optionally, additional unlisted items. Only terms clearly indicated to the contrary, such as "only one of' or "exactly one of," or, when used in the claims, "consisting of," will refer to the inclusion of exactly one element of a number or list of elements. In general, the term "or" as used herein shall only be interpreted as indicating exclusive alternatives (i.e. "one or the other but not both") when preceded by terms of exclusivity, such as "either," "one of," "only one of," or "exactly one of." "Consisting essentially of," when used in the claims, shall have its ordinary meaning as used in the field of patent law.

As used herein in the specification and in the claims, the phrase "at least one," in reference to a list of one or more elements, should be understood to mean at least one element selected from any one or more of the elements in the list of elements, but not necessarily including at least one of each and every element specifically listed within the list of elements and not excluding any combinations of elements in the list of elements. This definition also allows that elements may optionally be present other than the elements specifically identified within the list of elements to which the phrase "at least one" refers, whether related or unrelated to those elements specifically identified. Thus, as a non-limiting example, "at least one of A and B" (or, equivalently, "at least one of A or B," or, equivalently "at least one of A and/or B") can refer, in one embodiment, to at least one, optionally including more than one, A, with no B present (and optionally including elements other than B); in another embodiment, to at least one, optionally including more than one, B, with no A present (and optionally including elements other than A); in yet another embodiment, to at least one, optionally including more than one, A, and at least one, optionally including more than one,

B (and optionally including other elements); etc.

It should also be understood that, unless clearly indicated to the contrary, in any methods claimed herein that include more than one step or act, the order of the steps or acts of the method is not necessarily limited to the order in which the steps or acts of the method are recited.

In the claims, as well as in the specification above, all transitional phrases such as "comprising," "including," "carrying," "having," "containing," "involving," "holding," "composed of," and the like are to be understood to be open-ended, i.e., to mean including but not limited to. Only the transitional phrases "consisting of' and "consisting essentially of' shall be closed or semi-closed transitional phrases, respectively, as set forth in the United States Patent Office Manual of Patent Examining Procedures, Section 2111.03.