MITOTIC KINESIN INHIBITORS AND METHODS OF USE THEREOF

BACKGROUND OF THE INVENTION Priority of Invention

|0001] This application claims priority to United States Provisional Application Number

60/848,915 that was filed on 3 October 2006, which is hereby incorporated herein by reference in its entirety.

Description of the State of the Art

[0002] Among the therapeutic agents used to treat cancer arc the taxancs and vinca alkaloids, which act on microtubules. Microtubules arc the primary structural elements of the mitotic spindle, which is responsible for distribution of replicate copies of the genome to each of the two daughter cells that result from cell division. Il is presumed that disruption of the mitotic spindle by these drugs results in inhibition of cancer cell division and induction of cancer cell death. However, microtubules form other types of cellular structures, including tracks for intracellular transport in nerve processes. Because drugs such as taxancs and vinca alkaloids do not specifically target mitotic spindles, they have side effects that limit their usefulness.

|0003] Improvements in the specificity of agents used to treat cancer is of considerable interest, in part because of the improved therapeutic benefits that would be realized if the side effects associated with administration of these agents could be reduced. Traditionally, dramatic improvements in the treatment of cancer have been associated with identification of therapeutic agents acting tli rough novel mechanisms. Examples include not only the taxancs, but also the camptothccin class of lopoisomerasc I inhibitors. From both of these perspectives, mitotic kincsins arc attractive targets for new anti-cancer agents.

[0004] Mitotic kinesins arc enzymes essential for assembly and function of the mitotic spindle but are not generally part of other microtubule structures such as nerve processes. Mitotic kincsins play essential roles during ail phases of mitosis. These enzymes arc "molecular motors" that transform energy released by hydrolysis of ATP into mechanical force that drives the directional movement of cellular cargoes along microtubules. During mitosis, kinesins organize microtubules into the bipolar structure that is the mitotic spindle. Kincsins mediate movement of chromosomes along spindle microtubules, as well as structural changes in the mitotic spindle associated with specific phases of mitosis. Experimental perturbation of mitotic kincsin function causes malformation or dysfunction of the mitotic spindle, frequently resulting in cell cycle arrest and cell death.

(0005) Among the identified mitotic kincsins is kincsin spindle protein ("KSP"). KSP belongs to an evolutionarily conserved kinesin subfamily of plus end-directed microtubule motors

that assemble into bipolar homotetramers consisting of anliparallel honiodimers. During mitosis,

KSP associates with microtubules of the mitotic spindle. Microinjection of antibodies directed against KSP into human cells prevents spindle pole separation during prometaphase, giving rise to monopolar spindles and causing mitotic arrest and induction of programmed cell death. KSP and related kincsiiis in other non-human organisms bundle antiparallel microtubules and slide them relative to one another, thus forcing the spindle poles apart. KSP may also mediate in anaphase B spindle elongation and focusing of microtubules at the spindle pole.

[0006] Mitotic kinesins arc therefore attractive targets for the discovery and development of novel mitotic chemothcrapeutics.

J0007] Compounds that inhibit mitotic kinesins are known, for example, International Patent

Applications WO 2004/111024, WO 2005/035512, WO 2006/031348, WO 2006/044825, and WO

2006/1 19146.

J0008] Thiadiazolcs arc known, for example, WO 2004/1 11023, WO 2005/061707, WO

2006/101102, WO 2006/101 103, WO 2006/101 104, WO2006/101 105, and US 6,235,762.

SUMMARY OF THE INVENTION

(0009] The invention provides compounds that inhibit mitotic kinesins, in particular the mitotic kincsin KSP. The compounds arc useful as therapeutic agents, for example, for inhibiting the assembly or function of microtubule structures, including the mitotic spindle. [OOIOJ In one embodiment, the invention provides a compound of the invention that is a compound of Formula I:

|0011] or a salt thereof, R'-R ⁴ and X have any of the values defined herein.

[0012] In another embodiment, the invention provides a composition comprising a compound of the invention and a pharmaceutically acceptable carrier.

[0013] In another embodiment, the invention provides a method for inhibiting the proliferation of cells, comprising contacting said cells with an effective amount of a compound of the invention.

[0014] In another embodiment, the invention provides a method for inhibiting the proliferation of cells in an animal, comprising administering an effective amount of a compound of the invention to the animal.

[0015] In another embodiment, the invention provides a method for inhibiting abnormal cell growth, comprising contacting the abnormal ceils with an effective amount of a compound of the invention.

[0016] Tn another embodiment, the invention provides a method for inhibiting abnormal cell growth in an animal, comprising administering an effective amount of a compound of the invention to the animal.

|0017] In another embodiment, the invention provides a method for inhibiting one or more kincsins, comprising contacting the one or more kincsins with an effective amount of a compound of the invention.

[0018] In another embodiment, the invention provides a method for inhibiting one or more kincsins in an animal, comprising administering an effective amount of a compound of the invention to the animal.

[0019] In another embodiment, the invention provides a method for treating a microtuble- mcdiatcd condition in an animal, comprising administering an effective amount of a compound of die invention to the animal.

[0020] In another embodiment, the invention provides a method for inhibiting mitotic spindle formation in an animal, comprising administering an effective amount of a compound of the invention to the animal.

[0021] In another embodiment, the invention provides a method of treating a fungal or oϋicr cukaryotc infection in an animal, comprising administering an effective amount of a compound of the invention to the animal.

(0022] In another embodiment, the invention provides a kit for treating an abnormal cell growth condition, wherein said kit comprises:

[0023] a) a compound of the invention; and

[0024J b) instructions for use.

[0025] In another embodiment, the invention provides a compound of the invention for use in therapy.

[0026] In another embodiment, the invention provides the use of a compound of the invention in the manufacture of a medicament for inhibiting the proliferation of cells in an animal.

[0027] In another embodiment, the invention provides the use of a compound of the invention in the manufacture of a medicament for inhibiting abnormal cell growth in an animal.

[0028] In another embodiment, the invention provides the use of a compound of the invention in the manufacture of a medicament for inhibiting one or more kincsins in an animal.

|0029] In another embodiment, the invention provides the use of a compound of the invention in the manufacture of a medicament for treating a microtublc-mediated condition in an animal.

|0030] In another embodiment, the invention provides the use of a compound of the invention in the manufacture of a medicament for inhibiting mitotic spindle formation in an animal.

(0031] In another embodiment, the invention provides the use of a compound of the invention in the manufacture of a medicament for treating a fungal or other eukaryotc infection in an animal.

[0032] Additional advantages, other embodiments, and novel features of this invention arc set forth in part in the description that follows.

DETAILED DESCRIPTION OF THE INVENTION Definitions

(0033] The term "alkyl" as used herein refers to a saturated linear or branchcd-chain monovalent hydrocarbon radical having one to ten carbon atoms, wherein the alkyl radical may be optionally substituted with one or more subslilucnts. Examples of alkyl groups include, but arc not limited to, methyl, ethyl, n-propyl. isopropyl. butyl, isobutyl, sec-butyl, tcrt-butyl, pentyl. isopentyl, neopentyl, tert-pentyl, hexyl, 2-hexyl. 3-hexyl, 3-melhylpenlyl, heptyl, octyl and the like. (0034] The term "alkylenc" as used herein refers to a linear or branched saturated divalent hydrocarbon radical of one to ten carbon atoms, wherein the alkylene radical may be optionally substituted with one or more substitucnts. Examples of alkylene groups include, but arc not limited to, methylene, ethylene, propylene, 2-mcthylpropylcnc, pcntylcne and the like. (0035] The teπn "alkenyl" refers to a linear or branched-chain monovalent hydrocarbon radical having two to ten carbon atoms and at least one double bond, and includes, but is not limited to, ethenyl, propcnyl, l-but-3-cnyl, l-pcnt-3-enyl, l-hex-5-cnyl and the like, wherein the alkenyl radical may be optionally substituted with one or more substilucnts. The term includes radicals having "cis" and "trans" orientations, or alternatively, "E" and "Z" orientations. (0036] The teπn "alkcnylcne" refers to a linear or branched divalent hydrocarbon radical of two to ten carbons containing at least one double bond, wherein the alkcnylcne radical may be optionally substituted with one or more substitucnts. Examples include, but are not limited to, cthcnylcnc, propcnylenc and the like.

[0037] The term "alkynyl" refers to a linear or branched monovalent hydrocarbon radical of two to ten carbon atoms containing at least one triple bond. Examples include, but are not limited to, ethynyi, propynyl, butynyl, pentyn-2-yl and the like, wherein the alkynyl radical may be optionally substituted with one or more substitucnts.

[0038] The term "aikynylene" refers to a linear or branched divalent hydrocarbon radical of two to ten carbons containing at least one triple bond, wherein the αlkynylcnc radical may be optionally substituted with one or more substitucnts.

[0039] The term '"animal" includes birds and mammals (c.g, domestic mammals and humans).

(0040] The term "cycloalkyl" refers to a saturated or partially unsaturated monocyclic monovalent hydrocarbon radical having from three to ten carbon atoms, as well as to a polycyclic (e.g., bicyclic or tricyclic) monovalent hydrocarbon radical, such as a saturated or partially unsaturated monocyclic hydrocarbon radical fused to one or more other saturated or partially unsaturated monocyclic radicals. Examples of cycloalkyl groups include, but are not limited to. cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl and the like. The cycloalkyl may be optionally substituted at one or more substitutable positions with one or more substituents. Bicyclic cycloalkyls include those having 7 to 12 ring atoms arranged, for example, as a bicyclo [4,5]. [5,5], [5,6] or [6.6] system, or as bridged systems such as bicyclo[2.2.1]heptano. bicyclo[2.2.2]octanc, and bicyclo[3.2.2 hionane.

[0041] The term '"heterocyclc ^" ' refers to a 3 to 8 mcmbcred saturated or partially unsaturated monocyclic ring comprising one or more hetcroatoms selected from N(R ^X ), O, or S; or an ortho- fused bicyclic ring of about eight to twelve ring atoms derived therefrom, particularly a bcnz- derivative or one derived by fusing a propylene, trimcthylene, or tetramethylcne diradical thereto; wherein each R" is independently absent or is H. O, (Ci-COalkj l, -C(=θχCι-G»)alkyI, phenyl or benzyl. Examples of heterocycles include, but are not limited to, pyrrolidinyl, totrahydrofuranyl, dihydrofuranyl, tcirahydrothicnyl, tetrahydropyranyl, dihydropyranyl, tctrahydrothiopyranyl, pipcridino, morpholino, thiomorpholino, thioxanyl, pipcraκinyl, homopipcrazinyl, azctidinyl, oxctanyl, thietanyl, homopiperidinyl. oxepanyl, thicpanyl, oxazepinyl, diazepinyl, thiazepinyl, 1,2,3,6-telrahydropyridinyl, 2-pyrrolinyl, 3-pyrrolinyl, indolinyl, 2H-pyranyl, 4H-pyranyl, dioxanyl, 1.3-dioxolanyl, pyrazolinyl, dithianyl, dithiolanvl, dihydropyranyl, dihydrothienyl, dihydrofuranyl. pyrazolidinylimidazolinyl, and imidazolidinyl.

[0042] The tcnn "hctcroaryl" refers to a monocyclic aromatic ring containing five or six ring atoms consisting of carbon and one to four hcteroatoins each selected from the group consisting of non-peroxide oxygen, sulfur, and N(R ^X ), or an ortho-fused bicyclic heterocyclc of about eight to ten ring atoms derived therefrom, particularly a benz-dcrivative or one derived by fusing a propylene, trimethylcnc, or tetramethylcne diradical thereto; wherein each R ^x is independently absent or is H, O, (CrC,)aIkyl, phenyl or benzyl. Examples of hctcroaryl groups include, but are not limited to, pyridinyl, imidazolyl. pyrimidinyl, pyrazolyl. triazolyl, pyrazinyl, telrazolyl, fuiyl, thienyl, isoxazolyl, thiazolyl, oxazolyl, isothiazolyl. pyrrolyl, quinolinyl, isoquinolinyl, indolyl,

beiiziniida/.olyl. benzofuranyl. cinnolinyl. indazolyl, indolizinyl, phthalazinyl, pyridaziiryl, triazinyl, isoindolyl. ptcridinyl, purinyl, oxadiazolyl, Iriazolyl, Ihiadiazolyl, thiadiazolyl, furazanyl, bcnzofurazanyl, bcnzothiophcnyl, bcnzothiazolyl, bcnzoxazolyl, quinazolinyl, quinoxalinyl, naphthyridinyl, and furopyridinyl.

[0043] The term "aryl" refers to a phenyl ring or an ortho-fused bicyclic carbocycle having aboul nine to ten ring atoms wherein at least one ring is aromatic, particularly a benz-derivative or one derived by fusing a propylene, trinicthylenc, or tctramclhylcnc diradical thereto. Examples of aryl include phenyl, naplUhyl, dihydronaphthyl, and tetrahydronaphthyl. [0044] The term "halo" refers to fluoro, bromo, chloro. or iodo.

[0045] The term "microtuble-mcdialcd condition" includes, but is not limited to, cellular proliferative diseases, for example cancer, hyperplasias, restenosis, cardiac hypertrophy, immune disorders, infectious disease, fungal or other cukaryotc infections, and inflammatory disease.

(0046) The term "abnormal cell growth" refers to cell growth that is independent of normal regulatory mechanisms (e.g., loss of contact inhibition). This includes, but is not limited to. the abnormal growth of: (1) tumor cells (tumors) that proliferate by expressing a mutated tyrosine kinase or ovcrcxpression of a receptor tyrosine kinase; (2) benign and malignant cells of other proliferative diseases in which aberrant tyrosine kinase activation occurs; (3) any tumors that proliferate by receptor tyrosine kinases; (4) any tumors that proliferate by aberrant serine/threonine kinase activation; and (5) benign and malignant cells of other proliferative diseases in which aberrant serine/threonine kinase activation occurs.

(0047) The tcπn "treating," includes reversing, alleviating, inhibiting the progress of, or preventing the disorder or condition to which such term applies, or one or more symptoms of such disorder or condition. The term "treatment," as used herein, unless otherwise indicated, refers to the act of "treating" as defined immediately above.

Compounds of the Invention

[0048] In general, the invention relates to compounds of Formula I:

(0049] and to salts thereof, wherein:

[0050] X is O or S;

[0051] R ^! and R ³ are each independently aryl or hctcroaryl, wherein said aryl and hctcroaryl arc each optionally substituted with one or more groups independently selected from halo, cyano,

nitro, fluoroniethyl, diiluoromclhyl, trifluoronictliyl, difluoromethoxy, triπuoromcthoxy, azido, - OR ^a , -NR ¹ R", -C(=0)R ³ , -C(=0)0R ^a . -NR"C(=0)0R ^d , -Q=O)NR ⁰ R", (C-Cιo)alkyl, (C3- Ci _o )cycloalkyl, (C ₂ -Cι,.)alkcnyl. and (C ₂ -Cio)alkynyl;

[0052] R ² is (Ci-Co)alkyl, (C ₂ -C,o)alkcnyl, (C _r Cκ.)aIkynyi, (C ₃ -C, ₀ )cycloalkyl, NR ^j R\ aryl. heterocycle, or hetcroaiyl, wherein each (Cι-Cιo)alkyl. (CrCio)alkcnyl, (C ₂ -Cιo)alkynyl. (C ₃ - Cio)c>cloalk)'l, C(=NR ^h )R', aryl, and heteroaryl of R ² is optionally substituted with one or more R ⁰ ; (0053] R ⁴ is Z-NR ⁸ -C(=NR ^h )R ^! , Z-NR ⁸ -C(=NR ^h )NR ⁱ R ^k , Z-C(-NR ^h )NR ^j R ^L , Z-O-

NR ^ε C(=NR ^h )NR ^J R ^k , Z-O-NR ⁸ -C(=NR ^h )R', Z-NR ^m -NR ⁿ -C(=NR ^h )R', Z-0-NR'R ^k , Z-O-Z- C(=NR ^h )NR ^J R ^k . Z-O-N=C(R^:, Z-NR ^B -C(=CHR ^q )NR ^J R\ or Z-NR ^m -NR"-C{=NR ^h )NR ^J R ^k . provided that when R ⁴ is Z-O-NR ^e C(=NR ^h )NR ^J R\ Z-0-NR ⁸ -C(=NR ^h )R', or Z-0-NR ^J R ^k . then R ^J and R ⁸ arc not OR";

J0054] Z is (Ci-Cιo)alkylene, (CrCιo)alkenylene, or (C ₂ -C io)alkynylene, each optionally substituted with one or more halo;

(0055] R", R ^b , and R ^c are each independently selected from H, (Ci-Co)alkyL (C ₂ -

Cιo)alkenyl, (C2-Ciυ)alkynyl, aryl, hclcroaryl. heterocycle and aiyl(Ci-C3)alkyl, wherein each R ^a and R ¹ ' is optionally substituted with one or more groups independently selected from oxo (with the proviso that it is not on an aromatic ring), halo, cyano, nitro. -OR ^e , -NRTl^ difluoromethyl, trifluoromethyl, difluoromcthoxy, trifluoromcthoxy, azido, (Ci-Cio)alkyl, and (C ₃ - Cιo)cycloalkyl; or any NR ^a R ^b taken together form a lieterocyclc, wherein said heterocyclc is optionally substituted with one or more groups independently selected from (with the proviso that it is not on an aromatic ring), halo, cyano, nitro, OR ^C , -NR ^c R ^f , difluoromethyl, trifluoromethyl, difluoromethoxy, trifluoromcthoxy, azido. (Cι-Cιo)alkyl. and (C ₃ -Cιo)cycloalkyl; or any NR ^b R ^c taken together form a heterocyclic ring, wherein said hctcrocyclc ring is optionally substituted with one or more oxo (with the proviso that it is not on an aromatic ring), halo, cyano, nitro, OR', -NR ^c R ^r , difluoromethyl, trifluoromethyl, difluoromethoxy, trifluoromethoxy, azido, (Ci-Cio)alkyl, and (C ₃ - Cιo)cycloalkyl; or R" and R ^u together with the atoms to which they arc attached form a hctcrocyclc; or R ^a and R ⁸ together with the atoms to which they arc attached form a hctcrocyclc; (0056] R ^d is (Ci-Ciu)alkyl, (C _r Ci ₀ )alkcnyl, (C ₃ -Cio)cycloalkyl, aryl, hotcroaryl, heterocyclc or aryl(Cι-C ₃ )alkyl, wherein each R ^d is optionally substituted with one or more groups independently selected from oxo (with the proviso that it is not on an aromatic ring), halo, cyano, nilro, OR ^C , - NR ⁴ R ¹ I difluoromethyl, trifluoromethyl. difluoromethoxy, trifluoromethoxy, azido, (Cι-Cιo)alkyl, and (C3-Cιo)cycloalkyl; or R ^a and R ^d together with the atoms to which they are attached form a hctcrocyclc;

[0057] R ^c and R' are independently selected from H, (Cι-Cio)alkyl, (C _; -Cιo)alkcnyL (C ₂ -

Cio)alkynyl, and (C ₃ -Cιo)cycloalkyl; or NR ^c R ^f taken together form a heterocycle;

|00581 R ^E , R ^ra and R" are independently H, OR ^P , or (Ci-Cio)alkyl.; or R ¹ and R ^m together with the atoms to which they are attached form a hcterocyclc; or R ⁸ and R ^J together with the atoms to which they are attached form a hcterocyclc; or R ^a and R ⁸ together with the atoms to which they arc attached form a hcterocycle; or R' and R" together with the atoms to which they arc attached form a heterocycle; or R" ¹ and R ⁿ together with the atoms to which they are attached form a heterocycle; or R> and R ^ra together with the atoms to which they are attached form a heterocycle; or R' and R" together with the atoms to which they arc attached form a helcrocyclc;

[0059] R ^h is H, -OR ^P , cyano, -C(=O)N(R ^P ) ₂ , -C(=O)R ^P , or alky! optionally substituted with one or more groups independently selected from halo, cyano, -OR ^P , -N(R ^p )j, and aryl; or R ^h and R ^j together with the atoms to which they arc attached form a hctcrocyclc; or R ^h and R' together with the atoms to which they arc attached form a heterocyclc;

(0060] R' is H or (Cι-Cιo)alkyl optionally substituted with one or more groups independently selected from halo, nitro, cyano, -OR ^P , -N(R^, and aryl; or R' and R ^ra together with the atoms to which they are attached form a heterocycle; or R ^h and R ¹ together with the atoms to which they arc attached form a heterocycle; or R' and R" together with the atoms to which they are attached form a hcterocycle;

10061] R ^j and R ^k arc independently H, -OR ^P , C(=O)R ^P , hcterocycle, aryl, hctcroaryl, (Cr

COcycloalkyl or (Ci-Cjo)alkyl optionally substituted with one or more groups independently selected from halo, cyano, -OR ^P , -N(R ^p )i, and aryl; or -NR ^J R ^k together form a heterocycle; or R ⁸ and R' together with the atoms to which they arc attached form a helcrocyclc; or R ^h and R' together with the atoms to which they are attached form a heterocyclo; or R" and R ^k together with the atoms to which they arc attached form a hclcrocycle; or R> and R ^m together with the atoms to which they arc attached form a hetcrocyclc; or R ^j and R ⁿ together with the atoms to which they arc attached form a heterocycle;

[0062] each R ⁰ is independently oxo (provided it is not on a nitrogen, oxygen or an unsaturated carbon), halo, cyano, nitro, azido, -NR ^a R ^b , -Ct=O)R", -C(O)OR ⁰ . -OC(O)R", -NR*C(O)0R ^d , -C(=0)NR ^a R ^b , -NR°C(O)NR ^b (0R ^c ), -NR°C(=0)NR ^b R ^c , -NR°C(NCN)NR ^b R ^c , -OR ³ , (Ci-Cio)alkyl. (C ₃ -C io)cycloalkyl, (CrCicύaLkenyl, (C ₂ -Cio)alkynyl, aryl, hclcroaryl, aryl(C _r COalkyl, hctcroaryl(Ci-C.Oalkyl ₃ heterocycle, hcterocycle(Cι-C ₃ )alky], or -0P(O)(0R") ₂ , wherein said (Ci-Cιo)alkyl. (C ₃ -Cιo)cycloalkyl, (C2-Cιo)alkcnyl, (CrCιo)aikynyl, aryl, hctcroaryl, aryl(Cι- COalkyl, hetcroaryl(Ci-C ₃ )alkyL heterocycle and hoterocycle(Ci-C ₃ )alkyi are optionally substituted with one or more groups independently selected from oxo (with the proviso that it is not on an aromatic ring), halo, cyano, nitro, hydroxy, -OR ⁰ , NR°R ^b , difluoromcthyl, trifluoromcthyl, difluoromethoxy, trifluoromcthoxy. azido.. -C(O)R ⁰ , -C(O)OR", -OC(O)R", -NR"C(O)0R ^b , -C(O)NR"R ^b , -NR ^a C(O)NR ^b R ^c _; and -NR"C(NCN)NR ^b R ^c ;

(0063) eacli R ^p is independently H, (Ci-Cιo)alkyl, -P(=0)(0H) ₂ , acetyl, 2-aminopropanoyl, aininoacctyl. or mcthoxycarbonyl;

[0064] each R ^q is independently (Cι-Cio)alkyl, (C ₂ -Cio)aikcnyl, (C ₂ -Ci ₀ )aikynyl, (Cr

Cιo)cycloalkyl, halo, cyano, nitro, -NR"R ^h , -C(=O)R ^P , or OR ^P ; and

(0065] each R ^r is independently (Ci-Cιo)alkyl, (C ₂ -Cio)alkcnyl, (C ₂ -Ci o)alkynyl, (C ₃ -

Cιo)c>cloalkyl. aryl, or Or -C(R^ ₂ together form a (Cj-Ciojcycloalkyl. (0066] Compounds of Formula I include compounds wherein R ¹ and R ³ are each independently aryl or hetcroaryl, wherein said aryl and hclcroaryl arc each optionally substituted with one or more groups independently selected from halo, cyano, nitro, difluoromcthyl, Irifluoronicthyl, difluoromcthoxy, trifluoromcthoxy, azido, -OR", -NR°R ^b , -C(=O)R", -C(=O)OR", -NR°C(=0)0R ^d , -C(=O)NR ^a R\ (C ₁ -Co) ₃ IkS l, (C3-C ₁₍ ,)cycloalkyl, (C ₂ -C, ₀ )alkcnyl ₅ and (C ₂ - Cio)alkynyl.

|0067] Certain compounds of the invention can exist as two or more tautomeric forms. A

"taulomcr" is one of two or more structural isomers that exist in equilibrium and arc readily converted from one isomeric form to another, such as structures formed by the movement of a hydrogen from one site to another within the same molecule. Other tautomeric forms of the compounds may interchange, for example, via enolization/de-enolization and the like. Accordingly, the present invention includes all tautomeric forms of compounds of Formula I. (0068] The compounds of the invention may also possess one or more asymmetric centers; such compounds can therefore be produced as individual (R)- or (S)-stercoisomcrs or as mixtures thereof. Unless indicated otherwise, the description or naming of a particular compound in the specification and claims is intended to include both individual cnantiomers, diastereomers mixtures, raceniic or otherwise, thereof. Accordingly, this invention also includes all such isomers, including diaslcrcomcric mixtures and pure cnantiomers of the compounds. Diastcrcomcric mixtures can be separated into their individual diastereomers on the basis of their physical chemical differences by methods known to those skilled in the art, for example, by chromatography or fractional crystallization. Enantiomcr mixtures be separated by any suitable method, e.g.. by converting the cnantiomers into a diastcrcomcric mixture by reaction with an appropriate optically active compound (e.g., alcohol), separating the diastereomers. and converting (e.g., hydrolyzing) the individual diastereomers to the corresponding pure cnantiomers. The methods for the determination of stereochemistry and the separation of stereoisomers are well known in the art (see discussion in Chapter 4 of "Advanced Organic Chemistry", 4th edition, J. March, John Wiley and Sons, New York, 1992). [0069] In one embodiment of the invention. X is S.

|0070] In one embodiment of the invention, R' is aiyl that is optionally substituted with one or more groups independently selected from halo, cyano, difluoroπiethyl, trifluoromelhyl, difluoromethox>, trifluoromclhoxy, -OR", -NR ^a R ^b , -Q=O)R", -Q=O)OR", -NR ⁴ C(=0)0R ^d , -C(=O)NR ^a R ^b . (Cι-C ₁₁ ))alkyl, (C _r C, ₀ )cycloalkyl, (C ₂ -C,,,)alkcnyl, and (C ₂ -C, ₀ )alkynyl. (0071] In one embodiment of the invention, R ¹ is phenyl that is optionally substituted with one or more groups independently selected from halo, cyano, difluoroniethyl, trifluoromethyl, difluoromcthoxy, trifluoromethoxy, -OR", -NR ^a R ^b , -C(=O)R°, -C(=O)OR ^a , -NR"C(=O)OR ^d , (C ₃ -Cιo)cycloalkyl, (C ₃ -Cio)alkcnyl, and (C _r Cio)alkynyl. (0072] In one embodiment of the invention, R ¹ is phenyl that is optionally substituted with one or more groups independently selected from halo, cyano, difluoromcthyl, trifluoromethyl. difluoromethoxy, trifluoromethoxy. -OR ^a . -NR'R ¹ ', -C(=O)R\ -C(=0)0R ^a , and (Ci-Co)alkyl. (0073) In one embodiment of the invention, R ¹ is phenyl that is optionally substituted with one or more halo.

(0074] In one embodiment of the invention, R ¹ is 2,5-difluorophcnyl.

[0075] In one embodiment of the invention, R ^: is (CrCio)alkyl, optionally substituted with one or more R".

(0076] In one embodiment of the invention, each R" is independently oxo, -NR ^* R ^b , -OR",

(C ₃ -Cιo)cycloalkyl, aryl, or -OP(O)(OR"):.

|0077] In one embodiment of the invention, R ² is 1-methoxycthyl, 1-hydroxyelhyl, isopropyl, lert-bulyl, ethyl, propyl, 1-methylpropyl, 1-cthylρropyl, 1 -hydroxypropyl, l-hydroxy-2- mcthylpropyl, 1 -hydroxy-2,2-dimctln lpropyl, α-hydroxycyclopropylmcthyl, α- aminocyclopropylmcthyl, α-(N-methylamino)cyclopropylmcthyl _s 1-ethoxyethyl, 1- trifluoromethoxyelhyl, 1 -(cyclopropyloxy)ethyl, l-methoxy-2-methylpropyl, 1-hydroxy-l- mcthylcth> l, l-nicthox\-l-inethylethyl. 1-mcthoxypropyl, l-mcthoxy-2,2-din»cthylρropyl, l-(2- mcthylρropoxy)cthyl, I -(isopropoxy)ethyl. l-(/er/-butoxy)cthyl, I -(2-mcthoxyclhoxy)cthyl, I- (phenoxy)ethyl. l-(2-pyridyloxy)ethyl, l -(3-pyridyloxy)ethyl, l-(benz\'loxy)ethyl, α- methoxybcnzv'l, 2-mcthox>'etliyl. I -(N-acetylamino)-2-mcthylpropyl, l-amino-2-niethylpropyl, acetyl, 3-aminoprop> 1, 2-amino-l.l-dimcthylcthyl. l-amino-2-methylpropyl, l-amino-2,2- dinicthylpropyl.. l-methoxycyclopropylmethyl, 1-methoxycthyl, or

(0078] In one embodiment of the invention, R ^: is NR ^J R ^k .

(0079] In one embodiment of the invention, R" is λ'-incthoxy-λ'-methylaniino, N-mcthoxy-

/V-cthylaιnino, λ'-cthoxy-/V-incthylamino. yV-t-butoxλ'-λ'-methylaniino, N-

isopropoxy-N-cthylamino, //-cthoxy-λMsopropylamino, tf-elhoxy-λM-butylamino, NJJ- dimcthylamino, M-hydroxy-iV-mcthylamino, methylamino, λ'-(4-pipcridyl)-λ ^r -nicthylamino, /V-(I- acctylpipcrid-4-yl)-iv ^* -mcthylamino, λf-(3-aminopropyl)-/V-mcthylamino, iV-hydroxymcthyl-M- nicthylamino, N-phosphorylmethyl-iV-nicthylainino, /V-hydroxymcthyl-λ''-ethylamino, JV-(2- hydroxyethyl)-/V-cthylamino. λλ^3-hydroxypropyl)-M-ethylaτnino, iV-(4-hydrox>'butyl)-λ ^r - cthylamino, λ^-(2-aminoct!iyl)-λ ^r -cthylamino, /V-(3-nminopropyl)-/V-cthylamino, N-(4-aminobutyl)- #-cthylaniino, 1-azctidinyl, 1 -pyrrol idinyl, 1-pipcridino, or 4-moφholino.

[0080J In one embodiment of the invention, R ² is (C3-Cio)cycloalkyl optionally substituted with one or more R°.

[0081] In one embodiment of the invention, R" is cyclobutyl, cyclopcntyl, I- mctliylcyclopropyl, l-trifluoromethylcyclopropyl, 1-hydroxycyciopropyl, 1-methoxycyclopropyl or 2-fluorocyclohexyl.

[0082] In one embodiment of the invention, R ² is Q=NR^)R*.

J0083] In one embodiment of the invention, R ² is I-hydroxyiminoclhyl or 1- niethoxyiininoethyl.

[0084] In one embodiment of the invention, R ² is hctcrocyclc, aryi, or hctcroaryl, wherein each R" is optionally substituted with one or more R°.

|0085] In one embodiment of the invention, R ² is 3-pyridyl, 2-pyridyl, 3-mcthyl-2-fur\ l, 2- melhyl-5-thiazolyl, 3-aminophenyl, 5-methyl-2-lliienyl, or tetraliydrofuranyl. (0086] In one embodiment of the invention, R ² is 1-incthoxy ethyl, l-hydroxycthyl, or N- mcthoxy-λ'-methylamino.

(0087] In one embodiment of the invention. -C(=O)R ² is (S)-2-methoxypropanoyl or (S)-2- hydroxypropanoyl.

(0088] In one embodiment of the invention, R ³ is aryl that is optionally substituted with one or more groups independently selected from halo, cyano, nitro, difluoromcthyl, trifluoromcthyl, diπuoromcthoxy, triπuoromcthoxy, azido, -OR", -NR ^a R ^b , -C(=O)R ^a , -C(=O)OR°, -NR"C(=O)OR ^d , -C(=O)NR ⁿ R ^b , (Ci-Cι,))alkyl, (C ₃ -C ₁₍₎ )cycloalkyl, (C ₂ -C| _ft )alkenyl, and (C ₂ -C, ₀ )alkynyl. (0089] In one embodiment of the invention, R ^λ is phenyl that is optionally substituted with one or more groups independently selected from halo, cyano, nitro, difluoromcthyl, trifluoromethyl. difluoromethoxy, trifluoromethoxy, azido, -OR ^a , -NR ^a R ^b , -C(=O)R ^a , -C(=O)OR ^a , -NR ^a C(=O)OR ^d , -C(=O)NR"R ^b , (Cι-Cii))alkyl, (Cj-C ₎₀ )cycloalkyl, (C ₂ -Cι _υ )alkcnyl, and (C ₂ -Ci u)alkynyl. (0090] In one embodiment of the invention, R ³ is phenyl.

(0091] In one embodiment of the invention, R ⁴ is Z-NR ⁸ -C(=NR ^h )R ⁱ ,

Z-NR ^B" C(=NR ^h )NR ^j R ^k , Z-NR"'-NR"-C(=NR ^h )R ⁱ , Z-NR ⁸ -C(=CHR ^<l )NR ^j R ^k , or Z-NR ^m -NR ⁿ - C(=NR ^h )NR'R ^k .

[0092] In one embodiment or the invention, R ⁴ is Z-C(=NR ^h )NR ^J R ^k .

(0093] In one embodiment of the invention, R ⁴ is Z-O-NR ⁸ C(=NR ^h )NR ^J R ^k , Z-O-NR ⁸ -

C(=NR ^h )R\ Z-O-NR ^j R ^k , Z-O-Z-C(=NR ^h )NR ^j R ^k , or Z-O-N=C(R^.

[0094] In one embodiment, R ^h is CN, C(O)NH ₂ , C(O)Me, OMc ₅ CH ₃ or H.

10095] In one embodiment, R ⁸ is H.

[0096] In one embodiment, R ^j and R ^k are independently H, CH ₃ or C(O)Me.

[0097] In one embodiment of the invention, R ⁴ is selected from the following structures:

(0098] In one embodiment of lite invention. Ii* has the following structure:

(0099] In one embodiment of the invention, Z is (C|-Cio)alkylcnc optionally substituted with one or more halogens.

(0010O] In one embodiment of the invention, Z is ethylene, propylene, methylene, or

-CH ₂ CH ₂ CF ₂ -. (001011 In another embodiment of the invention., compounds of Formula II are provided:

wherein R ² and R ⁴ arc as defined above.

Salts

(001021 The compounds of the invention include salts of the compounds of Formula I. Such salts may be useful as intermediates for preparing and/or purifying compounds of Formula I and/or for separating enantiomcrs of compounds of Formula I. In one particular embodiment, ihc invention provides a pharmaceutically acceptable salt of a compound of Formula I.

(00103) The term "pharmaceutically acceptable salt," includes salts that arc not biologically or physiologically undesirable. A compound of Formula 1 may posses a sufficiently acidic functional group, a sufficiently basic functional group, or both, so that it can form a salt. Examples of such salts include those prepared by reaction of a compound with an organic or inorganic acid or

base. Since a single compound of Formula I may include more than one acidic or basic moiety, the compounds of the present invention may include mono, di or tri-salts in a single compound. (00104| Salts may be prepared by any suitable method, for example, by treatment of the free acid with an inorganic or organic base, or by ion exchange chromatography. Compound Preparation

[00105] The compounds may be prepared using techniques available in the art using starting materials that arc readily available or that can be synthesized using methods known in the art. For example, the compounds can be prepared the reaction routes illustrated in Schemes I-Vll below. (00106) In the preparation of some analogues such as described in Schemes 1-VIl. the use of appropriate protecting groups for functionality contained within the various substitucnts may be desirable. In these cases, protection and deprotection of said functionality can be accomplished using standard methods known by and available to those skilled in the art. For a general description of protecting groups and their use. sec T. W. Greene, Protective Groups in Organic Synthesis, John Wiley & Sons, New York, 1991.

[00107] For illustrative purposes. Schemes I-VII show general methods for preparing the compounds of the present invention as well as key intermediates. For a more detailed description of the individual reaction steps, see the Examples section below. Those skilled in the art will appreciate that other synthetic routes may be used to synthesize the compounds of the invention. (00108] Although specific starting materials and reagents are depicted in the Schemes and discussed below, other starting materials and reagents can be substituted to provide a variety of derivatives and/or reaction conditions. In addition, many of the compounds prepared by the methods described below can be further modified in light of this disclosure using conventional chemistry well known to those skilled in the art to provide other compounds of Formula I.

[00109| Scheme 1 illustrates a method of preparing compounds of Formulas F-3, 1-4, 1-5, 1-6 and 1-7. 1-1 can be synthesized in a manner similar to that previously described (U.S. Patent Application 60/620,048, published as WO 2006/044825). Nitrile 1-1 can be converted to imidatc 1-2 wherein Q is oxygen by treatment with an anhydrous solution of HCI in methanol, cthanol or other appropriate alcohol at lowered or ambient temperatures, l-l can be converted to thioimidate 1-2 wherein Q is sulfur by treatment with HCI and the appropriate thiol in neat thiol or a suitable solvent such as methanol, cthanol, ether or benzene. In one embodiment, 1-1 is subjected to anhydrous cthanolic HCl at 0 ⁰ C and allowed to waπn to room temperature to afford the hydrochloride salt of I- 2 wherein Q is oxygen and R^ is ethyl. 1-2 can then be converted to amidine 1-3 by treatment with ammonia or the appropriate amine in cthanol, methanol or other appropriate solvent. Preferably, 1-2 is treated with an amine in methanol at room temperature to afford 1-3 or a tautomer thereof. 1-4 can be obtained by subjecting the hydrochloride salt 1-2 to cyanamidc in alcoholic solvent, followed by treatment with tricthylaminc or other suitable base and the appropriate amine. Alternatively, 1-4 can be generated from 1-3 by treatment with cyanogen bromide or cyanogen chloride and triethylamine or other suitable base in an appropriate solvent such as cthanol, acctonitrile, chloroform or DMF. I- S is synthesized from 1-2 by treatment with an alkoxyaminc. hydroxylamine, or a salt thereof in the presence of triethylaminc or other suitable base in cthanol, methanol, or other suitable solvent. Preferably, 1-2, wherein Q is oxygen and Rj is ethyl, is treated with the appropriate alkoxyaminc hydrochloride in cthanol at room temperature to afford 1-5 wherein R ^p is alkyl. 1-6 can be produced from 1-2 by subjecting 1-2 to the appropriate mono-substituted amine at room temperature or elevated temperature in cthanol, methanol, or other appropriate solvent.

Scheme II

|00110| Scheme II illustrates a method of preparing compounds of Formulas 11-2, II-3 and

II— I. Amines of the Formula II-l arc prepared as previously described (U.S. patent application 60/620,048, published as WO 2006/044825). Amine H-I can be com cried to H-2 by treatment with a guanidinylating reagent such as, but not limited to, a substituted or unsubstitutcd S- methylisothiourca, carbodiimide, 3,5-dimcthyl-l//-pyrazolc-l-carboxamidinc or aminoiminomethanesulfonic acid reagent in an appropriate solvent and at elevated temperature if necessary.

|001 U| Alternatively, II-2 can be prepared by subjecting H-I to a iV-protccted guanidinylating reagent such as, but not limited to, di-Boc-S-mcthylisothiourca. di-CBκ- triflylguanidine, or W,W-bis(tørt-butoxγcaώonyl)-l//-pγrazolc-l-carboxamidinc in a suitable solvent followed by subsequent removal of the protecting groups under the appropriate conditions to provide H-2 or a tautomer thereof. In one embodiment, amine II- 1 is treated with N^T-bh(lerl- butoχycarbonyl)-l//-ρyra/olc-l-carboxamidine in letrahydrofuran, followed by treatment wiih hydrochloric acid in dioxanc to remove the fcrf-butoxycarbonyl protecting groups to afford H-2 or a tautomer thereof wherein R ⁸ , R ^h and R ^J are hydrogen. Compound H-3 can be obtained from amine II-l by treatment with the appropriate imidatc or imidate salt in combination with a suitable base, in an alcoholic solvent at elevated temperature. Preferably, amine II-l is treated with the hydrochloride salt of an ethyl imidatc and tπethylaminς in rcfluxing anhydrous cthαnol to afford 11-3 or a tautomer thereof. Compound H-4 is prepared by treatment of amine H-I with the appropriate cyanoimidatc or cyanoiniidatc salt in combination with a suitable base, in an alcoholic solvent. Preferably, amine H-I is treated with an jV-cyano ethyl imidate hydrochloride and tricthylaminc in anhydrous cthanol to afford 11-4 or a tautomer thereof.

Scheme III

|00112j Scheme 111 illustrates a method of preparing compounds of Formula III-2. Amine

H-I can be converted to compound IH-I by treatment with cyanogen bromide or cyanogen chloride in the presence of a suitable base and appropriate solvent. In one embodiment, amine II-l is treated with cyanogen bromide and trielhylaminc in methylene chloride. Compound IH-2 can be prepared by treatment of compound HI-I with excess of an alkoxyamine or alkoxyaminc salt in the presence of an appropriate base in a suitable solvent optionally at elevated temperatures. Preferably, IH-I is

treated with excess alkoxyainine hydrochloride salt and trielhylamine in ethanol at reflux temperature to provide 111-2 or a tautomer thereof.

V o "- ^{1 N R} V o "v- ^N 1 ^R V I ιv- ^N 2

Scheme IV

(00113| Scheme IV illustrates a method of preparing compounds of Formulas IV-I and 1V-2.

Compound IV-I can be prepared in one step from amine H-I by treatment with a cyano- guanidinylating reagent such as, but not limited to, an N-cyanocarbamimidate, an .S'-alkyl-#- cyanocarbamimidothioatc, or dicyanamide salt. Alternatively, compound IV-I can be synthesized in a two-step procedure from H-I by initial treatment with a reagent including, but not limited to. an N- cyanocarbonimidatc or an /V-cyanocarbonimidodithioatc, optionally in the presence of a suitable base, followed by subsequent treatment with ammonia or the appropriate amine. In one embodiment, the hydrochloride salt of amine H-I is subjected to diphcnylcyanocarbonimidatc and triethylamine in isopropanol at room temperature, followed by treatment with ammonia or the appropriate amine in methanol at reflux temperature. Compound IV-2 can be prepared by treatment of compound IV-I with acid and walcr in a suitable solvent. Preferably, compound IV-I is treated with hydrochloric acid in methanol and water to provide compound IV-2 or a tautomer thereof.

Scheme V

|00114| Scheme V illustrates a method of preparing compounds of Formulas V-2 and V-3.

Alkoxyaniincs of the Formula V-I can be prepared by a similar route to the preparation of amines of the Formula H-I using the appropriate W-prolccted ketone precursor. Compound V-2 can be prepared by treatment of alkoxy amine V-I with the appropriate iinidatc or imidatc salt in combination with a suitable base, in an alcoholic solvent at elevated temperature. Preferably, alkoxyaniine V-I is treated with the hydrochloride salt of an ethyl imidate and triethylamine in rcfluxing absolute cthanol to afford V-2 or a tautomcr thereof. Compound V-3 can be prepared by treatment of alkoxyaniine V-I with a guanidinylating reagent such as, but not limited to, a substituted or unsubstitutcd S-nieϋiyHsolhiourcα, carbodiimide, 3.5-dimethyl-IW-pyrazole-l- carboxamidine or aminoiminomethanesulfonic acid reagent in the appropriate solvent and at elevated temperature if necessary. Alternatively, V-3 can be prepared by subjecting V-I to a N- protcctcd guanidinylating reagent such as, but not limited to, di-Bco-S'-mcthylisothiourca, di-CBz- trifylguanidinc, or λW-bis(/t'r^butoxycartκ>nyl)-lA ^r -ρyrazole-l-carboxamidinc in a suitable solvent followed by removal of the protecting groups under the appropriate conditions to provide V-3 or a tautomer thereof. In one embodiment alkoxyaminc V-I is treated with NJf-bis(iert- butoxycarbonyl)-l//-pyrazolc-I-carboxamidine in tetrahydrofuran, followed by treatment with hydrochloric acid in dioxanc to remove the fcτ/-butoxycarbonyl protecting groups to afford V-3 or a tautomer thereof wherein R ^h , R ^J and R ^k are hydrogen,

Scheme VI

(00115| Scheme Vl illustrates a method of preparing compounds of Formulas VI-2 and VI-3.

Alkoxyaniincs of the Formula Vl-I can be prepared by a similar route to the preparation of amines of the Formula IM using the appropriate /V-prolected ketone precursor. Compound VI-2 can be

prepared by treatment of alkoxyamine VI-I with the appropriate iniidatc or imidale salt in combination with a suitable base, in an alcoholic solvent at elevated temperature. In one embodiment, alkoxyamine VI-I is treated with the hydrochloride salt of an ethyl iniidatc and tricthylaminc in refluxing absolute cthanol to afford VI-2 or a tautonicr thereof. Compound VI-3 can be prepared by treatment of alkoxyamine VI-I with a guanidinylating reagent such as, but not limited to, a substituted or unsubstitutcd S-mcthylisothiourca, carbodiimidc, 3,5-dimcthyI-l//- pyrazole-1-carbo.vamidinc or aminoiminonicthancsulfonic acid reagent in the appropriate solvent and at elevated temperature if necessary. Alternatively, Vl-3 can be prepared by subjecting VI-I to a /V-protectcd guanidinylating reagent such as, but not limited to, di-Boc-S-methylisolhiourca, di- CBz-trifylguanidinc, or /V^V-bis(/er/-butoxycarbonyl)-l//-pyrazole-l-carboxaniidine in a suitable solvent followed by removal of the protecting groups under the appropriate conditions to provide VI-3 or a tautoincr thereof, in one embodiment, alkoxyamine VI-I is treated with Nfi*-bis((ert- butoxycarbonyl)-lW-pyrazoIc-l-carboxamidinc in tctrahydrofuran, followed by treatment with hydrochloric acid in dioxanc to remove the /irf-butoxycarbonyl protecting groups to afford VI-3 wherein R ^h , R ¹ and W are hydrogen.

Scheme VII

[00116] Scheme VII illustrates a method of preparing compounds of the Formulas VII-2 and

VII-3. Hydrazines of the Formula VIM can be prepared by a similar route to the preparation of amines of the Formula II-l using the appropriate λ'-protcctcd ketone precursor. Compound VII-2 can be prepared by treatment of hydrazine VII-I with the appropriate iniidatc or iniidatc salt in combination with a suitable base, in an alcoholic solvent at elevated temperature. Preferably,

hydrazine VII-I is treated with the hydrochloride salt of an ethyl imidate mid tricthylainine in refluxing absolute elhanol to aiTord VII-2 or a tautomer thereof. Compound VI1-3 can be prepared by treatment of hydrazine VIf-I with a guanidinylaling reagent such as, but not limited to, a substituted or unsubstitυted S-mcthylisothiourea, carbodiiinide, 3,5-dimethyl-l//-pyrazole-l- carboxamidiiic or aminoiminoπicthanesulfonic acid reagent in the appropriate solvent and at elevated temperature if necessary. Alternatively, VII-3 can be prepared by subjecting VII-I to a N- protectcd guanidinylating reagent such as, but not limited to, di-Boc-S-mcthylisothiourca, di-CBz- trifylguanidine, or /VJV'-bis(/frt-butoxycarbonyl)-l//-pyrazole-l-carboxainidine in a suitable solvent followed by removal of the protecting groups under the appropriate conditions to provide VII-3 or a taulomer thereof. In one embodiment, hydrazine VIl-I is treated with N^F-bis{ιerl- butoxycarbonyl)-l/r ^' -pyrazole-l -carboxaniidine in tetrahydrofuran, followed by treatment with hydrochloric acid in dioxane to remove the /e/7-butoxycarbonyl protecting groups to afford VII-3 wherein R ^h , R' and R" are hydrogen.

(00117) In one embodiment, the invention provides a method for preparing a compound of

Formula 1 or a salt thereof comprising:

(00118] a) deprotccting a corresponding compound that comprises one or more protecting groups;

(00119) b) for a salt of a compound of Formula I, fonning a salt from a corresponding compound of Formula I;

[00120] c) for a compound of Foπnula I, wherein R ⁴ is Z-CC=NH)N^R ¹ , by reacting a corresponding compound wherein R ⁴ is Z-CC=NH)OR _d , wherein R _d is (Cι-Cio)alkyl with a corresponding amine HNR ^J R ^k ;

(00121) d) for a compound of Formula I, wherein R ⁴ is Z-C(=NCN)NR ^j R ^t , reacting a corresponding compound wherein R ⁴ is Z-CC=NH)ORd, wherein R^ is (Cι-C]o)alkyl with cyanamidc followed by treatment with a corresponding amine HNR ^J R ^k ;

(00122] e) for a compound of Foπnula I, wherein R ⁴ is Z-C(=NOR ^P )NH;, reacting a corresponding compound wherein R ⁴ is wherein Rj is (Cι-Cio)alkyl with a corresponding amine NH ₂ (OR ^P ):

(00123] 0 for a compound of Formula I, wherein R ⁴ is Z-NR ^β -C(=NR ^h )NR ^J R ^k , reacting a corresponding compound wherein R ⁴ is Z-NHR ⁸ with a guanidinylating reagent; (00124] g) for a compound of Formula I, wherein R ⁴ is Z-NR ⁸ -CC=NR ^h )NR ^J R ^k , reacting a corresponding compound wherein R ⁴ is Z-NHR ⁸ with an yV-protectcd guanidinylating reagent, followed by deprotection;

(00125] h) for a compound of Formula I, wherein R ⁴ is Z-NR ⁸ -C(=NR ^h )R', reacting a corresponding compound wherein R ⁴ is Z-NHR ⁸ with a corresponding imidate or imidate salt;

(001261 i) for a compound of Formula I, wherein R ⁴ is Z-NR ^e -C(=NCN)R', reacting a corresponding compound wherein R* is Z-NHR ⁸ with a corresponding cyanoimidntc or cyanoimidatc salt:

ϊ00127J j) for a compound of Formula I, wherein R ⁴ is Z-NR ^S -C(=NH)NR ^J (OR ^P ), treating a corresponding compound wherein R ⁴ is Z-NR ⁸ -CN with a corresponding alkoxyamine or alkoxyamine salt;

(00128) k) for a compound of Formula I, wherein R ⁴ is Z-NR ⁸ -C(=NR ^h )NR ^J R ^k , wherein R ^h is aminocarbonyl, treating a corresponding compound wherein R ^h is cyano with acid in an aqueous solvent;

(00129| 1) for a compound of Formula I, wherein R ⁴ is Z-0-NR ⁸ -C(=NR ^h )R', treating a corresponding compound wherein R ⁴ is Z-O-NHR ⁸ with with a corresponding iniidatc or imidatc salt;

(00130) m) for a compound of Foπnula 1, wherein R ⁴ is Z-O-NR ⁸ C(=NR ^h )NR ^J R ^k , treating a corresponding compound wherein R ⁴ is Z-O-NHR ⁸ with with a corresponding guanidinylating reagent;

[001311 n) for a compound of Formula I, wherein R ⁴ is Z-O-NR ⁸ C(=NR ^h )NR ^J R\ treating a corresponding compound wherein R ⁴ is Z-O-NHR ⁸ with with an //-protected guanidinylating reagent, followed by deprotection;

(00132] o) for a compound of Formula I ₅ wherein R ⁴ is Z-N(OR ^p )C(=NR ^h )R', treating a corresponding compound wherein R ⁴ is Z-NH(OR ^P ) wilh a corresponding imidaic or imidaic salt:

[001331 P) for a compound of Formula I, wherein R ⁴ is Z-N(OR ^p )C(=NR ^h )NR ^J R ^k , treating a corresponding compound wherein R ⁴ is Z-NH(OR ^P ) with a corresponding guanidinylating reagent;

(00134| q) for a compound of Formula I, wherein R ⁴ is Z-N(OR ^p )C(=NR ^h )NR ^J R\ treating a corresponding compound wherein R ⁴ is Z-NH(OR ^P ) with a corresponding N-protected guanidinylating reagent, followed by doprotection;

(00135| r) for a compound of Formula I, wherein R ⁴ is Z-NR ^m -NR ⁿ -C(=NR ^h )R', treating a corresponding compound wherein R ⁴ is Z-NR ^m -NR ⁿ -H with a corresponding iniidate or iniidatc salt;

[001361 s) for a compound of Formula I ₅ wherein R ⁴ is treating a corresponding compound wherein R ⁴ is Z-NR ^m -NR"η with a corresponding guanidinylating reagent; or

[00137J t) for a compound of Formula I, wherein R ⁴ is Z-NR ^m -NR ⁿ -C(=NR ^h )NR ^J R ^k , treating a corresponding compound wherein R ⁴ is Z-NR ^m -NR ⁿ -H with a corresponding ^-protected guanidinylating reagent, followed by deprotection.

USE

(00138) The compounds of the ύwention find use in a variety of applications. As will be appreciated by those skilled in the art, mitosis may be altered in a varict) of ways. That is, one can affect mitosis cither by increasing or decreasing the activity of a component in the mitotic pathway. Stated differently, mitosis may be affected (e.g., disrupted) by disturbing equilibrium, either by inhibiting or activating certain components. Similar approaches may be used to alter meiosis. (00139| In one embodiment, the compounds of the invention arc used to modulate mitotic spindle formation, thus causing prolonged cell cycle arrest in mitosis. The lcnn "modulate mitotic spindle formation" means altering mitotic spindle formation, including increasing and decreasing spindle formation. The term "mitotic spindle formation" refers to organization of microtubules into bipolar structures by mitotic kinesins. "Mitotic spindle dysfunction" refers to mitotic arrest and monopolar spindle formation.

(00140] The compounds of the invention arc useful to bind to and/or modulate the activity of a mitotic kincsin. In an embodiment, the mitotic kincsin is a member of the bimC subfamily of mitotic kinesins as described in U.S. Patent No. 6,284,480. In a further embodiment, the mitotic kincsin is human KSP, although the activity of mitotic kinesins from other organisms may also be modulated by the compounds of the present invention. In this context, modulate means either increasing or decreasing spindle pole separation, causing malformation, i.e.. splaying, of mitotic spindle poles, or otherwise causing morphological perturbation of the mitotic spindle. Also included within the definition of KSP for these purposes arc variants and/or fragments of KSP. In addition, other mitotic kinesins may be inhibited by the compounds of the present invention. [00141 ] The compounds of the invention are useful for treating diseases and conditions caused by abnormal cell growth or cellular proliferation. Disease states that can be treated by the methods and compositions provided herein include, but are not limited to, cancer, autoimmune disease, arthritis, graft rejection, inflammatory bowel disease, and proliferation induced after medical procedures, including, but not limited to. surgery, angioplasty, and the like. It is appreciated that in some cases the cells may not be in a hypcrprolifcrativc or hypoprolifcrativc state (abnormal state), but still require treatment. For example, during wound healing, cells may be proliferating "normally", but proliferation enhancement may be desired. Similarly, in the agriculture arena, cells may be in a "normal" state, but proliferation modulation may be desired to enhance a crop by directly enhancing growth of a crop, or by inhibiting the growth of a plant or organism that adversely affects the crop. Thus, in one embodiment, the invention herein includes application to cells or individuals that arc afflicted or may eventually become afflicted with any one of these disorders or states.

[00142| The compounds of the present invention may also be useful as antifungal agents, by modulating the activity of the fungal members of the bimC kinesin subgroup, as described in U.S.

Patent No. 6,284,480.

[00143] It is believed that the compounds of the present invention can render abnormal cells more sensitive to treatment with radiation for purposes of killing and/or inhibiting the growth of such cells. Accordingly, this invention further relates to a method for sensitizing abnoπnal ceils in an animal to treatment with radiation, which comprises administering to the animal an amount of a compound of the invention, which amount is effective in sensitizing abnormal cells to radiation treatment.

(00144J Although the compounds of the invention are particularly useful as therapeutic agents for use in warm-blooded animals (including humans), they are also useful whenever it is required to inhibit the effects of KSP kinesin. Thus, they arc also useful as pharmacological standards in the development of new biological tests and in the search for new pharmacological agents.

Combinations

(00145] The compounds of this invention may be used alone or in combination with other therapeutic agents. Accordingly, in one embodiment, the invention provides a method for treating a disorder in a mammal that comprises administering to said mammal a therapeutically effective amount of a compound of the present invention in combination with another therapeutic agent, e.g., an anti-tumor agent, radiation therapy, an inhibitor of one or more mitotic kincsins, a PPAR-γ agonist, a PPAR-δ agonist, a gene therapy agent, an inhibitor of inherent multi-drug resistance (e.g. p-glycoprotcin inhibitors), an anti-emetic agent, an an immunologic-enhancing agent, an agent useful in the treatment of anemia, or an agent useful in the treatment of neutropenia.

(00146) In one embodiment, the invention also provides a composition comprising 1) a compound of the invention: 2) another therapeutic agent; and 3) a pharmaceutically acceptable carrier.

[00147J Anti-tumor agents that can be administered or formulated with compounds of the invention include, but arc not limited to:

[00148] (i) antiprolifcrativc/anti-ncoplastic drugs and combinations thereof, as used in medical oncology, such as alkylating agents (for example, cisplatin, carboplatin, cyclophosphamide. nitrogen mustard, melphalan, chlorambucil, busulphan and nitrosoureas): anti-metabolites (for example, antifolates such as such as fluoropyriinidines like 5-fluorouracil and tcgafur, raltitrexed, methotrexate, cytosinc arabinsidc, hydroxyurea, or, one of the preferred anti-metabolites disclosed in

European Patent Application No. 239362 such as N-(5-[N-(3,4-dihydro-2-mcthyl-4-oxoquinazolin-

6-ylmelhyl)-N-inediylamino]-2-lhcnoyl)-L-glutamic acid); antitumor antibiotics (for example, anthracyelines like adriamycin, bleomycin, doxorubicin, daimomycin, epirubicin, idarubicin, mitomycin -C, daclinomycin and mithramycin); antimitotic agents (for example, vinca alkaloids like vincristine, vinblastine, vindesine and vinorelbinc and taxoids like taxol and taxoterc): and topoisotnerase inhibitors (for example epipodophyllotoxins like eptoposide and teniposide, amsacrinc, topotecan and campothecin);

[00149) (ii) cytostatic agents such as anti-estrogens (for example, tamoxifen, toremifene, raloxifene, droloxifene and iodoxyfcnc), estrogen receptor down regulators (for example, fulvestratrant), anti-androgons (for example, bicalutamidc, flu t amide, nilutamide, cyproxeronβ acetate and Casodcx* (4'-cyano-3-(4-fluorophenylsulphonyl)-2-hydroxy-2-mcthyl-3'- (trifluoromethyl)propionaiiilide)), LHRH antagonists or LHRH agonists (for example, goserelin, leuporclin and buscrclin), progestogens (for example, megestrol acetate), aromatase inhibitors (for example, anastrozolc, lctrorølc, vora/ole and exemestane) and inhibitors of 5α-rcductasc such as finasteride;

(001SO] (iii) agents that inhibit cancer cell invasion (for example, mctalloprolcinasc inhibitors like niarimastat and inhibitors of urokinase plasminogen activator receptor function); [00151J (iv) inhibitors of growth factor function like growth factor antibodies, growth factor receptor antibodies (for example, the anti-crbB2 antibody trasUimuzab |Herceptin*j and the anti- erbBl antibody cetuximab fC225]). farnesyl transferase inhibitors, tyrosine kinase inhibitors and serine-threonine kinase inhibitors (for example, inhibitors of the epidermal growth factor family tyrosine kinases such as N-(3-chloro-4-fluorophcnyl)-7-mclhoxy-6-(3- morpholinopropoxy)quinazolin-4-amino (gefitinib, AZDl 839), N-(3-cthynyIphenyI)-6,7-bis(2- methoxyelhoxy)quinazolin-4-aniine (erlotinib, OSI-774) and 6-acrylamido-N-(3-chloro-4- iluorophcnyl)-7-(3-moφholinopropoxy)quinazolin-4-amine (CI 1033)), inhibitors of the platelet- derived growth factor family and inhibitors of the hcpatocytc growth factor family; [00152] (v) anli-angiogenic agents such as those that inhibit the effects of vascular endothelial growth factor (for example, the anti-vascular endothelial cell growth factor antibody bcvacizumab fAvaslin*]. compounds such as those disclosed in PCT Publication Nos. WO 97/22596, WO 97/30035, WO 97/32856, and WO 98/13354) and compounds that work by other mechanisms (for example, linomidc, inhibitors of intcgrin αvβ3 function, MMP inhibitors, COX-2 inhibitors and angioslatin);

[00153] (vi) vascular damaging agents such as Combrctastatin A4 and compounds disclosed in PCT Publication Nos. WO 99/02166, WO 0/40529, WO 00/41669, WO 01/92224, WO 02/04434, and WO 02/08213;

|00154| (vii) antisense DNA or RNA therapies (for example, those that are directed Io the targets listed above such as ISlS 2503, and anti-ras antisense);

[00155J (viii) gene therapy approaches, including for example GV AX™, approaches to replace aberrant genes such as aberrant p53 or aberrant BRCAl or BRCA2, GDEPT (gcnc-direclcd enzyme pro-drug therapy) approaches such as those using cytosine deaminase, thymidine kinase or a bacterial nitroreductase enzyme and approaches to increase patient tolerance to chemotherapy or radiotherapy such as multi-drug resistance gene therapy; 1001561 (ix) interferon:

(00157) (x) immunotherapy approaches, including for example cx-vivo and in-vivo approaches to increase the immunogcnicity of patient tumor cells, such as transfccliou with cytokines such as intcrlcukin 2, inlcrlcukin 4 or granulocyte-macrophage colony stimulating factor, approaches to decrease T-cell anergy, approaches to using transfected immune cells such as cytokinc-transfcctcd dendritic cells, approaches using cytokinc-lransfcctcd tumor cell lines and approaches using anti-idiotypic antibodies; and

[00158] (xi) miscellaneous agents such as intercalating antibiotics, signal transduction inhibitors, cell cycle inhibitors, enzyme inhibitors, retinoid receptor modulators, protcasome inhibitors, biological response modifiers, anti-hormones, targeted antibodies, HMG-CoA reductase inhibitors, and prenyl-protein transferase inhibitors.

(00159| Inhibitors of mitotic kincsins that can be administered or formulated with compounds of the invention arc described in PCT Publication Nos. WO 00/130,768, WO 01/30768, WO 01/98278, WO 03/050,064, WO 03/050,122, WO 03/049,527, WO 03/049,679, WO 03/049,678, WO 03/39460 WO 03/079,973, WO 03/088,903, WO 03/094,839, WO 03/097,053, WO 03/099,211, WO 03/099,286, WO 03/103..575, WO 03/105,855, WO 03/106,426, WO 04/032,84O ₅ WO 04/034,879, WO 04/037,171, WO 04/039,774, WO 04/055,008, WO 04/058,148, WO 04/058700 and WO 04/064,741.

[00160] PPAR-γ and PPAR-δ agonists that can be administered or formulated with compounds of the invention include proglitazone, rosiglatazone, gene therapy agents, and inhibitors of inherent multi-drug resistance (e.g. p-glycoprotcin inhibitors).

[00161) Neutropenia treatment agents that can be administered or formulated with compounds of the invention include, for example, a hematopoietic growth factor, which regulates the production and function of neutrophils such as a human granulocy te colony stimulating factor, (G- CSF). An example of a G-CSF is filgrastim.

[00162] Immunologic-cnhancing agents that can be administered or formulated with compounds of die invention include levamisole, isoprinosine and Zadaxin.

Pharmaceutical Compositions

(001631 The compounds of the invention may be administered by any convenient route, e.g. into the gastrointestinal tract (e.g. rcctally or orally), the nose, lungs, musculature or vasculature or transdcnnally. The compounds may be administered in any convenient administrative form, e.g. tablets, powders, capsules, solutions, dispersions, suspensions, syrups, sprays, suppositories, gels, emulsions, patches etc. Such compositions may contain components conventional in pharmaceutical preparations, e.g. diluents, carriers, pH modifiers, sweeteners, bulking agents, and further active agents. If parenteral administration is desired, the compositions will be sterile and in a solution or suspension form suitable for injection or infusion. Such compositions form a further aspect of the invention.

|00164] According to another aspect, the present invention provides a pharmaceutical composition, which comprises a compound of Formula I or a pharmaceutically acceptable salt thereof, as defined hereinabove. In one embodiment, the pharmaceutical composition includes the compound of Formula I together with a pharmaceutically acceptable diluent or carrier. Dosaecs

(00165} It will be understood that the specific dosage level and frequency of dosage for any particular subject may be varied and will depend upon a variety of factors including the activity of the specific compound of Formula I, the species, age. body weight, general health, sex and diet of the subject, the mode and time of administration, rate of excretion, drug combination, and severity of the particular condition, but can nevertheless be routinely determined by one skilled in die art. |00166] Although the amount of a compound of this invention that is combined with one or more excipicnts to produce a single dosage form will necessarily van' depending upon the subject treated, the severity of the disorder or condition, the rate of administration, the disposition of the compound and the discretion of the prescribing physician, an effective dosage will typically be in the range of about 0.001 to about 100 nig per kg body weight per day, preferably about 0.5 to about 35 mg/kg/day. in single or divided doses. For a 70 kg human, this would amount to about 0.0035 to 2.5 g/day, preferably about 0.05 to about 2.5 g/day. In some instances, dosage levels below the lower limit of the aforesaid range may be more than adequate, while in other cases still larger doses mm be employed without causing any harmful side effect. For further information on routes of administration and dosage regimes, see Chapter 25.3 in Volume 5 of Comprehensive Medicinal Chemistry (Corwin Hansch; Chairman of Editorial Board), Pergamon Press 1990. Kits

J00167] In another embodiment of the invention, an article of manufacture, or "kit", containing materials useful for the treatment of the disorders described above is provided. In one embodiment, the kit comprises a container comprising a compound of the invention. The kit may

further comprise a label or package insert on or associalcd with the container. Suitable containers include, for example, bottles, vials, syringes, and blister packs.

(00168) The container may be formed from a variety of materials such as glass or plastic.

The container may have a sterile access port (for example, the container may be an intravenous solution bag or a vial having a stopper pierccable by a hypodermic injection needle). [00169] The label or package insert may indicate that the composition is used for treating a given condition, such as cancer. In one embodiment, the label or package inserts indicates that the compound of the invention can be used to treat a disorder resulting from abnormal cell growth. The label or package insert may also indicate that the composition can be used to treat other disorders. Alternatively, or additionally, the kit may further comprise a second container comprising a pharmaceutically acceptable buffer, such as bacteriostatic water for injection (BWFI), phosphate- buffered saline. Ringer ^' s solution and dextrose solution. It may further include other materials desirable from a commercial and user standpoint, including other buffers, diluents, filters, needles, and syringes.

(00170] The kit may further comprise directions for the administration of the compound of the invention, and, if present, another therapeutic agent. For example, if the kit comprises a compound of the invention and a second therapeutic agent, the kit may further comprise directions for the simultaneous, sequential or separate administration of the compound of the invention and the secong therapeutic agent to a patient in need thereof.

[00171] Accordingly this invention also provides a kit for treating an abnormal cell growth condition, wherein said kit comprises a) a compound of the invention; and b) instructions for use. In certain embodiments, the kit further comprises c) a second therapeutic agent (e.g. an agent having anti-hypcrproHferativc activity). In one embodiment, the compound of the invention and the second therapeutic agent arc contained in separate containers. In another embodiment, the compound of the invention and the second therapeutic agent are in the same container. Assays

100172) The biological activities of the compounds of the invention can be evaluated with the following assays.

Enzyme assay

(00173] The activity of the compounds of the present invention may be determined by the following procedure. The assays were conducted at 30 ⁰ C in a Costar 3695 (96-wcll, polystyrene, '/it- area, clear) plate in a final volume of 50 μL. Hydrolysis of ATP was monitored in a system that coupled the product ADP to the oxidation of NADH using pyruvate kinase and lactate dehydrogenase. Assay mixtures contained the following: 20 inM K'Pipcs. pH 7.0, 0.01% Triton X- 100, 2% DMSO, 25 mM KCl, 2 inM MgCl ₂ , 1 inM DTT, 25 μM ATP, 1 mM

phospho(enol)pyruvatc ₅ 200 μM NADH, 7.9 U/mL pyruvate kinase. 9 U/mL lactate dehydrogenase. 0.25 μM bovine microtubules, 20 μM paclitaxcl and 20 nM Eg5. The concentration of inhibitor was typically varied over the range of 10-200,000 nM. The reaction was monitored kinclically in an absorbance-based plate reader for a period of 10 minutes. Velocities were estimated from linear fits to the progress curves and were expressed as POC (percent of uninhibited control wells). IC ₅ o's were estimated from the POC data using a standard 4-paramcter logistical model and compared to a control inhibitor run in each plate. In this assay, compounds of Examples 1-29 exhibited an IC ₅₀ of less than 50 μM. (00174) In this assay, compounds of Examples 1 -29 exhibited an IC ₅₀ of less than I μM.

Cell Viability Assav

|00175] The ability of the compounds of the present invention to inhibit cellular viability may be determined by the following procedure. Cells from a variety of established tumor cell lines, e.g. HcLa, were plated in Costar 3904 96-wcll plates, in growth medium, at a density that allowed for logarithmic growth over the period of the assay, and incubated at 37°C, 5% CO? overnight. The following day. compounds were added to the cells, at a final DMSO concentration of 0.5%. The concentration of inhibitor was typically varied over the range of 0.1-50,000 nM. Plates were then incubated as above. After a 72 to 96 hour incubation, 20 μL rcsazurin solution (Cell Titer Blue, Promcga G8081) was added to all wells and the plates incubated for a further period of time. Viable cells convert resazurin to resorufin, a fluorescent end-product. The fluorescent signal was determined in a fluorescent plate reader at 560 nni cxcitation/590 nm emission. The POC (percent of uninhibited control signal) was determined for each well, and the EC ₅₀ for inhibition of viability was determined from the inflection point of a standard 4-paranictcr logistical curve fitted to the values obtained. In this assay, compounds of Examples 1-29 exhibited an EC ₅ 0 of less than 50 μM. |00176] The compounds of Examples 1-29 exhibited an EC50 of less than 8.5 μM.

Mitotic Arrest Assav

(00177) Phosphorylation of Hislonc H3 on ScrlO. which peaks in mctaphasc. is a well- established indicator of mitosis. Phosphorylation in excess of control cells is indicative of mitotic arrest. The ability of the compounds of the present invention to induce mitotic arrest was determined by the following procedure. Cells from a variety of established tumor cell lines, e.g. HeLa, were plated in Greiner 655946, 96-well, poly-D-Iysine coated plates, in growth medium and incubated at 37°C, 5% CO ₂ overnight. The following day, compounds were added to the cells at a final DMSO concentration of 0.5%. The concentration of inhibitor was typically varied over the range of 0.1-50,000 nM. Once compound was added to the cells, plates were incubated as above. After approximately 16 hours, cells were fixed with cold methanol. Plates were blocked and labeled with primary antibody to phosphoHistone H3 (Santa Cruz Biotechnologies SC-8656-R, 1 μg/niL)

and to GapDH (RDI TRK-5G4-6C5). The cells were then labeled with secondary anlibodies that were conjugated to fluorescent dyes emitting in the near infrared range (Molecular Probes Alcxa 680, Rockland IR800) and scanned on a Licor Odyssey or Acrius. The integrated intensity of signal for phosphoHistonc H3 was normalized to the signal for GapDH for each well. The POC (percent of completely inhibited control signal) was determined for each well, and the EC ₅₀ for induction of mitotic arrest was determined from the inflection point of a standard 4-parametcr logistical curve fitted to the values obtained. In this assay, compounds of Examples 1-29 exhibited an EQo of less than 50 μM.

Tumor Growth Inhibition

JOOl 78J The ability of the compounds of this invention to inhibit tumor growth in vivo may be determined by the following procedure, using the HT-29 human colon tumor cell line obtained from the American Type Culture collection (ATCC). HT-29 tumor cells (3 - 5 x 10*, in a volume of 100 μL PBS) arc implanted subcutancously in the flank of female nude mice. Tumors arc allowed to grow to 150-250 mm ³ in size. The length and width of the tumors are measured with calipers, and tumor volume is calculated using the foπnula: volume = (length x width ² )/2. The mice are then randomized into treatment groups, typically 5 to 8 per group, based on tumor volume. The mice then receive λ chicle or compound on days 1, 5, 9 by IP injection. Dose is based on weight, measured the day of dosing. Tumor volume and weight are measured twice a week for the duration of the study. Mice arc kept on study until tumors grow to about 1500 mm ³ in size, afier which the mice are euthanized by CO ₂ inhalation. Tumor volume data are typically reported as V/V(0), where V = tumor volume on the day of measurement, and V(O) = tumor volume at day 1. (00179] The examples presented below are intended to illustrate particular embodiments of the invention, and arc not intended to limit the scope of the specification or the claims in any way.

EXAMPLES

[00180] In the examples described below, unless otherwise indicated, all temperatures are set forth in degrees Celsius. Reagents were purchased from commercial suppliers such as Aldrich Chemical Company, Lancaster, TCI or Maybridgc. and were used without further purification unless otherwise indicated. Tetrahydrofuran (THF), N.N-diniethylfomiamide (DMF), dichloromethanc (DCM), toluene, dioxanc and 1,2-dichlorocthane (DCE) were purchased from Aldrich in Sure seal bottles and used as received.

(00181) The reactions set forth below were typically carried out under a positive pressure of nitrogen or argon or with a drying tube (unless otherwise stated) in anhydrous solvents, and the reaction flasks were typically fitted with rubber septa for the introduction of substrates and reagents via syringe. Glassware was oven dried and/or heat dried.

[001821 Column chromatography was carried out on a Biolagc system (Manufacturer: Dyax

Corporation) having a silica gel column or on a silica ScpPak cartridge (Waters). (00183| ¹ H-NMR spectra were recorded on a Varian instrument operating at 400 MHz. ¹ H-

NMR spectra were obtained as CDCb solutions (reported in ppm), using chloroform as the reference standard (7.25 ppm). Other NMR solvents were used as needed. When peak multiplicities are reported, the following abbreviations are used: s (singlet), d (doublet), t (triplet), in (multiple!), br (broadened), dd (doublet of doublets), dt (doublet of triplets). Coupling constants, when given, arc reported in Hertz (Hz).

Example 1

/V-cvano-Jv ^' -(2-(5-(2.5-difluorophenyl)-3-((.S')-2-niethoxλ'propanoyl)- 2-phenyl-2.3-dihvdfO-1.3.4- thiadiazol-2-yl)clhyl)acctamidinc

[00184] Step A: Preparation of fe/7-butyl S-oxo-S-phcnylpropyicarbainatc: To a cooled (-

78 ⁰ C) solution of 3-(tcrt-butoχycarbonylamino)ρroρanoic acid (1.0 g, 5.3 mniol) in THF (53 mL) was added phenyllithium (9.9 mL, 16 minol, 1.6 M solution in cyclohexane/ether). After warming slowly to 0 ⁰ C and then stirring for 1 hour, the reaction mixture was quenched with saturated NH4CI (10 mL), diluted with water (70 mL) and extracted with ether. The combined organics were washed with brine (80 mL), dried over Na ₂ SO ₄ , filtered, and concentrated under reduced pressure. The residue was chromatographed (20% ethyl acetate in hcxancs) to provide the product (0.69 g, 59%) as yellow oil.

(00185) Step B: Preparation of 2.5-difluorobenzothiohvdra/ide hydrochloride: To a solution of 1,4-difluorobeιizcne (10Og, 876 inmol) in anhydrous THF (2.0 L) at -78°C was added a solution of vcc-butyllithium (1.4 M in cyclohexanc, 626 mL, 876 mmol) dropwise, maintaining the reaction temperature below -6O ⁰ C. The reaction mixture was allowed to stir at -78 ⁰ C for 30 minutes, and carbon disulfide (50.2 mL, 833 mmol) was then added dropwise. The reaction mixture was allowed to warm to room temperature over 30 minutes and then stirred at room temperature for 2 hours. Water (15 mL) was then added dropwise, and the mixture was then concentrated under reduced pressure. The crude brown semi-solid residue obtained was then suspended in water (600 mL) and treated with a solution of 2-chloroacctic acid (99.4 g, 1052 mmol) and sodium bicarbonate (73.6 g,

876 mmol) in water (200 mL). The mixture was stirred al room temperature for 14 hours and then acidified to pH 4 with 50% H ₂ SO4. The mixture was extracted with CH2CI.. and the combined organics were washed with brine, dried over Na ₃ SO ₄ , filtered and concentrated to afford crude 2- (2,5-difluorophenylcarbonothioylthio)acctic acid (214 g) as red-brown syrup. This material was then suspended in a cooled (O ⁰ C) solution of 0.5 M NaOH (1750 mL, 875 mmol), and hydrazine (54.0 mL, 1722 mmol) was then added dropwise. The reaction mixture was allowed to warm to room temperature and stir for 14 hours. The reaction mixture was then diluted with water and acidified to pH 4-5 using 1 N HCl. The mixture was then extracted with ethyl acetate, and the combined organics were washed with brine, dried over NajSCλi, filtered and concentrated to afford crude 2,5-difluorobcir/øthiohydrazidc as a red-brown oil (162.5 g). This oil was suspended in ether (3.5 L) and filtered. The filtered solution was then treated with 2 M HCl in ether while stirring vigorously. The mixture was stirred at room temperature for 15 minutes. The precipitate that formed was isolated by filtration and dried under vacuum to afford 2,5-difiuorobcnzotliiohydrazide hydrochloride (50 g, 26%) as a yellow solid.

[00186] Step C: Preparation of fer/-butyl 2-(>(2.5-difluorophcnyl)-2-phcnyl-2.3-dihvdro-

1.3.4-thiadiaxol-2-yl)cthylcarbamatc: To a cooled (O ⁰ C) solution of tør/-butyl 3-oxo-3- phcnylpropylcarbamaic (0.68 g, 2.73 mmol) and 2,5-difluorobcnzothiohydrazidc hydrochloride (0.613 g, 2.73 mmol) in EtOH (27 mL) was added triethylamine (0.57 mL, 4.09 mmol). After stirring at room temperature for 8 hours, the mixture was heated to 65 ⁰ C for 16 hours. The mixture was concentrated under reduced pressure and the residue was dissolved in ethyl acetate (100 mL). The solution was washed with water and brine (40 mL), dried over Na ₂ SO ₄ , filtered and concentrated under reduced pressure. The residue was chromatographed (30% ethyl acetate in hcxancs) to provide the crude product as a brown syrup which was used directly in the next step. [00187) Step D: Preparation of (2.V)-I -(2-(2-aminocthyl)-5-(2,5-difluorophenvπ-2-phcnyl-

1.3.4-thiadiay.ol-3(2/i ^r )-y π-2-mclhoxypropan- 1 -one hydrochloride: To a solution of (S)-2- methoxypropanoic acid (0.186 g, 1.79 mmol) and diisopropylethylamine (0.415 mL, 2.38 mmol) in DMF (10 mL) was added PyBOP (0.930 g, 1.79 mmol). After stirring for 5 minutes, a solution of (ert-bυlxl 2-(5-(2.5-difluorophcnyl)-2-phcnyl-2,3-diliydro-l,3,4-llHadi a2ol-2-) l)elhylcarbamatc (0.500 g, 1.19 mmol) in DMF (2 mL) was added. After stirring at room temperature for 17 hours, the mixture was treated with saturated NaHCOj and extracted with ethyl acetate. The combined organics were washed with water and brine (50 mL), dried over Na ₂ SO ₄ and concentrated under reduced pressure. The residue was chromatographed (4:1 to 2: 1 hexanes/ethyl acetate) to provide the Boc-protectcd product (263 mg, 44%) as a mixture of diastereomers. To a cooled (0 ⁰ C) solution of this material in dioxanc (6 mL) was added HCl (6.0 mL. 30.0 mmol, 5 M solution in dioxane).

After stirring at room temperature for 3 hours, the mixture was concentrated under reduced pressure. The residue was triturated with ether, filtered and dried under vacuum to provide the product (263 mg, 94%) as a yellow powder.

(00188) Step E: Preparation of ethyl M-cvanoacctiinidate: A mixture of cyanamidc (1.00 g,

23.8 mmol) and 1,1.1-triethoxycthane (4.34 mL, 23.8 mmol) in acetic anhydride (4.49 niL, 47.6 mmol) was heated to 100 ⁰ C in a distillation apparatus. After the volume of distillate diminished, the mixture was heated to 140°C, distilling most of the acetic acid. The residue was distilled under vacuum to afford the product (0.80 g, 30%) as colorless liquid (b.p. 9O ⁰ C at 20 mm). |00189| Step F: Preparation of /V-cvaιio-/V-(2-(5-(2.5-dinuorophenylV3-f(.S')-2- ntethoxypropanoyl)-2-phenyl-23-diln dro-1.3.4-thiadiayχ)l-2-yl ^' )ethyl)acetaniidine: To a solution of ethyl N-cyanoacctimidate (0.025 g, 0.22 mmol) and (2.$>l-(2-(2-aminoclhyl)-5-(2,5- difluoroρhenyl)-2 -phenyl- 1 ,3,4-thiadiazol-3(2//)-yl)-2-mcthoxypropan- 1 -one hydrochloride (0.018 g, 0.038 mmol) in EtOH (0.3 mL) was added diisopropylethylamine (0.033 mL, 0.19 mmol). After stirring at room temperature for 14 hours, the mixture was diluted with 10% Na^CC^ (30 mL) and extracted with dichloromcthanc. The combined organics were dried over Na^SO ₄ , filtered and concentrated under reduced pressure. The residue was chromatographcd (3% McOH in dichloromethane) to provide the product as a mixture of diastereomers (13.0 mg, 73% yield). MS ESI (+) m'z 472 (M+l) detected; ¹ H NMR (400 MHz, CDCl ₃ ) 67.51 (m, 2H).7.37 (m, 6H), 7.33 (m, 4H). 7.16 (m. 4H), 6.93 (br. t, IH, J = 4.7 Hz), 6.73 (br. t, IH, J = 4.7 Hz), 4.73 (m, 2H), 4.00 (m, 2H), 3.45-3.29 (m, 9H), 3.21 (m, I H), 2.82 (m, IH), 2.75 (m, IH), 2.16 (s, 3H), 2.15 (s, 3H), 1.46 (d ₅ 3H,J = 6.3 Hz), 1.43 (d, 3H ₅ J = 7.0 Hz).

Example 2

2-Cyano-l-(2-(5-(2.5-difluorophcnyl)-3-(( _t S')-2-mcthox\'propanoylV2-phcnyl-2,3-dihvdro-l,3 _r 4- thiadiazol-2-vOcthyDguanidino

(001901 To a solution of (2S)-l-(2-(2-mninoethyl)-5-(2,5-dιfiuorophenyl)-2-phcnyl-l, 3,4- thiadiazol-3(2H)-yl)-2-methoxypropan-l-one (23.4 mg. 0.0489 mmol) in isopropanol (1 mL) was added triethylaniinc (0.027 mL, 0.196 mmol) and diphcnyl-N-cyanocarbonimidatc (35.0 mg, 0.147 mmol). After stirring at room temperature for 1 hour, ammonia (3 mL, 7M solution in methanol)

was added. The reaction vessel was scaled and heated to 6O ⁰ C for 2 hours. The mixture was concentrated under reduced pressure, and the residue was chromatographed (3% methanol in dichloromethanc) to provide the product as a white solid and as a mixture of diastereomers (20.6 mg, 83% yield). MS APCI (+) m/z 473 (M+l) detected; ¹ H NMR (400 MHz, CD ₃ OD) δ 7.67-7.61 (m, 2H). 7.51-7.44 (m, 4H), 7.42-7.36 (m, 4H), 7.34-7.28 (m, 6H), 4.83-4.77 (m, 2H), 3.73-3.65 (m. 2H), 3.42 (s, 3H), 3,44-3.37 (m. 2H), 3.35-3.29 (m. 2H), 3.28 (s, 3H), 2.84-2.73 (ra, 2H). 1.49 (d, 3H, J - 7.1 Hz) ₅ 1.43 (d, 3 H, J = 7.1 Hz).

Example 3

2-Cvauo-l-f2-(5-(2.5-difluorophcnyl)-3-(ffl-2-mcthoxyprop anoylV2-phenyl-2.3-dihvdro-1.3.4- thiadiazol-2-yl)ethyl)-3-mothylguanidtnc

[001911 Prepared according to the method of Example 2, using methanamine in place of ammonia, to afford the product as a mixture of diastereomers. MS ESI (+) m/z 487 (M+l) detected; ¹ H NMR (400 MH/, CD ₃ OD) δ 7.68-7.62 (m, 2H), 7.52-7.44 (m, 4H), 7.42-7.36 (m, 4H), 7.34-7.27 (m, 6H), 4.83-4.77 (m. 2H), 3.80-3.77 (m, 2H), 3.51-3.44 (m, 2H), 3.43 (s, 3H), 3.40-3.30 (m. 2H), 3.28 (s, 3H) ₅ 2.88-2.80 (m, 2H) ₅ 2.79 (s, 3H), 2.78 (s ₅ 3H), 1.50 (d, 3H. J = 7.1 Hz).. 1.44 (d, 3H. J = 7.1 Hz).

Example 4

1 -f2-(5-r2.5-Dinuoroρhciiyn-3-(f»V)-2-methoxypropanoyi)-2-p henyl-2 _r 3-dihvdro- 13.4-thiadia∞l-2- yl)clhyl)-2-methoχvκuanidine hydroch loridc

[001921 Step A: Preparation of (2-(5-(2J-difluoropheuylV3-r(,SV2-methoxypropanovn-2- phenyl-23-dihvdro- 1.3,4-thtadiazol-2-yl)ethyl)cvaiiamido: To a solution of (2S>l-(2-(2- ainitiocthyI)-5-(2,5-difluorophcny l)-2-phcnyI- 1 ,3.4-lhiadiazol-3(2//)-yl)-2-methoxypropan- 1 -one (34.5 ntg, 0.0721 mmol) and cyanogen bromide (9.9 mg. 0.0938 mmol) in dichloromcthanc (I niL) was slowly added triethylaminc (25.5 mg, 0.252 mmol). After stirring at room temperature for 1 hour, the mixture was concentrated under reduced pressure to provide the crude product that was used without further purification.

(001931 Step B: Preparation of l-(2-(5-(2.5-difluorophcnyl)-3-((,S')-2-methoxypropano\ l)-2- phcnv]-23-diliydro-K3,4-tliiadiaw)l-2-yl)clhvn-2-methoxyttua nidine hydrochloride: To a solution of crude (2-(5-(2.5-diπuorophcnyl)-3-((»S>2-methoxypropanoyl)-2- phenyl-2,3-dihydro-l ,3,4- thiadiazol-2-yl)ethyi)cyanamide (31 mg, 0.072 mmol) and methoxyaminc hydrochloride (151 mg, 1.80 mol) in βthanol (3 niL) was added triethylamine (182 mg, 1.80 mmol). After heating to 70 ⁰ C in a sealed vessel for 16 hours, additional methoxyamine hydrochloride (151 mg, 1.80 mol) and triethylamine (182 mg, 1.80 mmol) was added, and the reaction mixture was heated to 70 ⁰ C in a scaled vessel for an additional 24 hours. The mixture was cooled to room temperature and diluted with ethyl acetate The salts were removed by filtration The filtrate was concentrated under reduced pressure, and the residue was chromatographed (4% methanol in dichloromclhanc with 0.5%NH4θH), and the isolated material was treated with excess HCI in McOH then concentrated to afford the product as a mixture of diastercotncrs (23 mg, 62% yield). MS APCI (+) m/z 478 (M+l) detected; ¹ H NMR (400 MHz, CD ₃ OD) δ 7.69-7.64 (m, 2H), 7.50-7.38 (m, 8H) ₅ 7.37-7.29 (m, 6H), 4.83-4.78 (m. 2H), 3.80-3.67 (m, 2H) ₅ 3.73 (s, 6H), 3.54-3.45 (m, 2H), 3.45-3.33 (m. 2H), 3.39 (s, 3H), 3.31 (s, 3H). 3.04-2.92 (m, 2H), 1.49 (d, 3R J = 7.1 Hz), 1.45 (d.3H, J = 7.1 Hz).

Example 5

l-(3-((λ')-5-(2.5-diπuorophcnyl)-3-((.S')-2-niethθxypropa noylV2-phenyl-2,3-dilivdro-l .3.4-tliiadiayχ>l-

2-yl)propyl)-2-methoxyauanidine hydrochloride

(001941 Step A: Preparation of 4-azido-l-phenylbutan-l-one: To a solution of 4-chloro-l- phenylbutan-1-one (26.4 mL, 164 mmol) in DMSO (200 ml) was added sodium azide (12.8 g, 197 mmol). The solution was warmed to 55°C and stirred for 16 hours. The cooled mixture was then

treated with water and extracted with ether. The combined organics were washed with water and brine, then dried over MgS04 and concentrated to provide the product as an orange oil (30.7 g,

100195) Step B: Preparation of 2-(3-a/idopropyl)-5-(2.3-difluorophenylV2-phcnyl-2.3- dihvdro- 1 ,3.4-thiadiazole: To a solution of 2,5-difiuorobenzothiohydrazidc (Example 1, Steps A and B; 1.5 g, 7.97 mrnol) in EtOH/dichloromethane (3: 1 , 16 mL) was added 4-azido-l-phenylbutan-l- onc (1.36 g. 7.17 mtnol). After stirring at room temperature for 16 hours, acetic acid (2 drops) was added, and the mixture was stirred for another 16 hours. The reaction mixture was then concentrated under reduced pressure and chromatographed (9: 1 hexanes/elhyl acetate) to provide the product (1.41 g, 41%) as a bright yellow synip.

|001961 Step C: Preparation of (SH-((S)-2-(3-aadopropyl)-5-(2.5-difluorophenvIV2-phenyl- l3.4-miadia*ol-3(2HVyl)-2^/-butv1diphenylsilyloxy)propan-l -one and (SVl-((R)-2-(3- aχidopropyl)-5-(2.5-difluoroρhenyl)-2-ρhenyl-1.3.4-thiadi a ^y ol-3(2H)-yl)-2-(/- butyldiphcιrylsilyloxy)propan-l-onc; To a solution of (S)-2-(<-butyIdiphcnyIsilyloxy)propanoic acid (339 mg, 1.09 mmol) in acelonitrile (6 mL) was added HATU (550 nig, 1.45 mmol) followed by DlEA (0.378 mL, 2.17 mmol). After stirring at room temperature for 15 minutes, a solution of 2-(3- azidopropyl)-5-(2,5-difluorophenyl)-2-phcnyl-2,3-dihydro-l,3 ,4-thiadiaa)lc (260 mg, 0.72 mmol) in acetonitrilc (4 mL) was added. After stirring at room temperature for 16 hours, the mixture was concentrated under reduced pressure and partitioned between saturated NaHCOj (50 mL) and ethyl acetate (50 mL). The aqueous lajcr was extracted with ethyl acetate, and the combined organic phases were washed with brine (20 mL), dried over Na ₂ SO^ filtered, and concentrated under reduced pressure. The brown oil was chromatographed (9:1 hexancs/cthyl acetate) to provide the less polar diastereomcr. (S)- l-((S)-2-(3-ayJdopropyl)-5-(2,5-difluorophenyl)-2-phcnyl-l,3 ,4- λiadiazol-3(2H)-yI)-2-(Nbutyldiphenylsiiyloxy)propan-l-one (121 mg) and the more polar diastereomcr, (S)-l-((R)-2-(3-azidopropyl)-5-(2,5-difluorophenyl)-2-phenyl -l,3,4-thiadiazol-3(2H)- yl)-2-(M>utyldiphcnyIsilyloxy)propan-l-one (175 mg) as pale yellow oils. Absolute stereochemistry was assigned by examination of a protein: inhibitor co-cryslal structure of Eg5 and (S)-I -((S)-2 -(3- aminopropji)-5-(2.5-difluorophcnyl)-2-phenyl-l,3.4-thiadiazo l-3(2H)->'l)-2-mcthoxypropan-l-onc. [00197J Step D: Preparation of (SV- 1 -((S)-2-(3-azidopropyl)-5-(2.5-difluorophcnyl)-2-phonyl- l.3.4-thiadiazo]-3f2H)-vπ-2-hydroxyproρan-l-onc: To a solution of (S>l-((S)-2-(3-azidopropyl)-5- (2,5-difluorophenyl)-2-phenyl-l,3,4-thiadiazol-3(2H)-yl)-2-( /-butj ldiphcnylsilyloxy)propan-l-onc (121 mg, 0.18 mmol) in THF (5 mL) at O ⁰ C was added TBAF (0.31 mL, I M, 0.31 mmol). After stirring at 0 ⁰ C for 1 hour and at room temperature for 1 hour, the mixture was treated with saturated NaHCC^ and extracted with ethyl acetate. The combined organics were washed with brine, dried

over Na^SOα, filtered, and concentrated. The brown oil was chroraatographed (4:1 hexancs/cthyl acetate) to provide the product (41 mg, 53%) as a pale yellow oil.

J00198J Step E: Preparation of (SVl -((S)-2-(3-azidopropyl)-5-(2,5-difluorophcm U-2-ρhenyl-

1.3.4-thiadiazol-3(2Hyyl)-2-mclhoxypropan-l -one: To a solution of (S)-I -((S)-2-(3-azidopropyl)-5- (2,5-difluorophenyl)-2-phenyl-l,3,4-thiadiazol-3(2H)-yl)-2-h ydrox} propan-l-onc (41 mg, 0.095 mniol) in DMF (2 niL) at O ⁰ C was added methyl iodide (50 μL, 0.48 mmol) followed by sodium hydride (10 mg, 60%). After stirring at 0 ⁰ C for 30 minutes and room temperature for 3 hours, the mixture was treated with saturated NH ₄ CI (20 mL) and extracted with ethyl acetate. The combined organic phases were washed with water and brine, dried over NajSO,, filtered, and concentrated under reduced pressure to proλ idc the product (40 mg, 94%) as a yellow oil. [001991 Step F: Preparation of (S)-I -(TS)-2-(3-antinopropyl)-5-(2.5-difluorophonylV2- phenyl-I.3.4-thiadiazol-3(2H)-y1)-2-nicthoxypropan-I-one: To a suspension of (S)-I -((S)-2-(3- azidopropyl)-5-(2,5-difluorophcnyl)-2-phcnyl-l,3,4-thiadiazo l-3(2H)-yl)-2-hydroxypropan-l-one (102 mg, 0.23 mmol) in MeOH (2.2 mL) was added cone. HCl (57 μL, 0.69 mmol) followed by 10% Pd/C (10 mg, wet, Degussa type). After stirring under a H; atmosphere for I hour, the mixture was filtered and concentrated under reduced pressure. The colorless glass was I ri hi rated with diethyl ether and filtered to provide lite di-HCl salt product as a white solid (89 mg. 79%). MS ESI (+) m/z 420 (M+l ) detected; ¹ H NMR (400 MHz, CDCb) δ 7.52 (m, IH), 7.45 (m, 2H), 7.35 (m, 2H), 7.28 (m, IH), 7.13 (m, 2H), 4.70 (m. I H), 3,40 (s, 3H). 3.27 (m, 1H) _? 2.88 (m, 2H), 2.43 (m, IH), 1.96 (in, IH). 1.57 (m, IH), 1.45 (d, 3H ₁ J= 7 H/.). Absolute stereochemistry assigned by examination of a protcin:inhibitor co-crystal structure of Eg5 and (S)-l-((S)-2-(3-aminopropyl)-5-(2,5- difluorophenyl)-2-phenyl4,3 _s 4-thiadiazol-3(2H)~yl)-2-methoxypropan-I-onc. [00200J Step G: Preparation oπ-(3-((,SV5-(2.5-difluorophenyl)-3-ff.S')-2-methox\ propanoyl)-

2-phenyl-2.3-dihvdro-1.3.4-thiadiaxol-2-vπpropyl)-2-methoxy guanidine hydrochloride: To a solution of (5)-l-((λ>2-(3-aminopropyl)-5-(2,5-diπuorophcnyl)-2-phe n\ l-l^,4-lhiadiazol-3(2//)- yl)-2-methoxypropan-l-onc (Example 5, Steps A-C; 52.1 ing, 0.106 mmol) and cyanogen bromide (13.4 mg, 0.127 mmol) in dichloromethane (1 m L) was slowly added tricthylaminc (35.3 mg, 0.349 mmol). After stirring for 20 minutes at room temperature, the mixture was concentrated under reduced pressure and dissolved in ethanol (2 mL). To this solution was added methoxyamine hydrochloride (600 mg, 7.18 mmol) and tricthylaminc (642 mg, 6.35 mmol). The reaction vessel was scaled and heated to 7O ⁰ C for 24 hours. The mixture was concentrated under reduced pressure and dissolved in ethyl acetate. The precipitate was removed by filtration and the filtrate was concentrated under reduced pressure. The residue was chromatographcd (3% methanol in dichloromethane with 0.5% NH ₄ OH), and the isolated material was irealed with excess HCl in

MeOH then concentrated to alTord the product as a white solid (7.3 ing, 13% yield). MS APCl (+) m/z 492 (M+l) detected; ¹ H NMR (400 MHz, CD ₃ OD) δ 7.65-7.60 (m, IH). 7.47-7.45 (m, 2H), 7.42-7.37 (ni, 2H), 7.35-7.29 (m, 3H), 4.79 (q, I H, J = 7.0 Hz), 3.73 (s _: 3H), 3.45-3.37 (m, 2H), 3.36 (s, 3H) ₅ 3.28-3.19 (m, IH), 2.60-2.51 (tn, IH), 2.19-2.08 (tn, IH), 1.71-1.60 (m, IH), 1.43 (d, 3H, J " 7.0 Hz).

Example 6

l-(3-((,S')-5-(2,5-difluorophenyl)-3-((. ^< ?)-2-mclhoxypropanoyl)-2-phenyl-2.3-dihvdro-1.3.4-thiadiazol -

2-yl)ρroρyl)guanidine hydrochloride

[002011 To a solution of (.S)-l-((S)-2-(3-aminopropyl)-5-(2 _> 5-diπuorophcnyl)-2-phenyl- 1 ,3,4- thiadiazol-3(2/0-y0-2-niclhoxypropan-l-onc (Example 5, Step F; 58 mg, 0.118 tnmol) and tricthylaminc (29.8 mg, 0.294 mniol) in THF was added λf,λP-di-Boc-l//-pyrazolc-l-carboxainidinc (45 mg, 0.145 mmol). After stirring at room temperature for 2 hours, the mixture was concentrated under reduced pressure. The residue was chromalographed (15% ethyl acetate in hexanes) to provide the Boc-protcctcd product (60 mg, 77%) as white foam. To 20 mg of this material was added HCI in dioxanc (1 niL of a 4M solution). After stirring at room temperature for 2 days., the mixture was concentrated and triturated with ether to provide the product as a while foam (10 mg. 63% yield). MS ESI (+) m/z 462 (M+l) detected: ¹ H NMR (400 MHz, CDjOD) δ 7.66-7.60, (m, I H), 7.51-7.44 (m, 2H), 7.43-7.36 (m, 2H) ₅ 7.35-7.28 (m, 3H), 4.83-4.76 (m, IH), 3.40-3.34 (nι, I H). 3.36 (s, 3H), 3.29-3.18 (m, 2H), 2.62-2.52 (m. I H). 2.17-2.05 (m, IH), 1.70-1.59 (m, IH), 1.43 (d, 3H,J= 6.0 Hz).

Example 7

l -ϋ-fffl)-5-(2.3-dif1uorophenvn-3-α.S')-2-nicthoxypropanoyl V2-pl)cnyl-2.3-dihvclro-1.3.4- thiadiaxoI-2-vI)propyl)Ruanidinc hydrochloride

[00202] Step A: Preparation of (S)-I -((/?)-2-(3-aminoρroρyl)-5-(2.5-diπuoroρhcnyl)-2- phcnyl-1.3.4-thiadiaxol-3(2fflλ"l)-2-incthoxypropan-t-onc: Prepared as described in Example 5. Steps A-G, using (S)- 1 -((R)-2-(3-azidopropyl)-5-(2.5-difluorophenyl)-2-phenyl- 1 ,3,4-thiadiazoI- 3(2H)-yl)-2-(tert-butyldiphenylsilyloxy)propan-l-oιie from Step C. MS ESI (+) mh 420 (M+l) detected; ¹ H NMR (400 MHx, CDCl ₃ ) δ 7.51 (m, IH), 7.44 (in, 2H), 7.36 (m, 2H), 7.29 (m, I H), 7.12 (m, 2H), 4.71 (q, IH, J = 6 Hz). 3.32 (s, 3H), 3.23 (m, IH), 2.84 (m, 2H), 2.43 (m, IH), 1.93 (m, IH), 1.50 (d, 3H, J = 6 Hz) ₅ 1.44 (m, 2H), 1.34 (in, IH). Stereochemistry was assigned by inference from (S)-H(S)-2-(3-aminopκ>pyl)-5-(2,S-diπuorophcnyl)-2-plic nyl-l^ _> 4-thiadt8zol- 3(2H)-\ l)-2-mcthoxypropan-l -one.

[00203] Step B: Preparation of 1 -(3-((/?)-5-(2.3-difluoTOphcnyl)-3-((6')-2-mcthoxypropanoyl) -

2-phenyl-2.3-dihvdro-1.3.4-ihiadiazol-2-v0propyDftuanidine hydrochloride: Prepared according to the method of Example 6, using (S)-l-((/?)-2-(3-aminopropyl)-5-(2,5-difluorophcnyl)-2-phcny l- 13,4-thiadiazol-3(2//)-yl)-2-mclhoxypropan-l-onc (Example 5, Steps A-F) in place of (.S>l-((5)-2- (3-aminopropyl)-5-(2 _J 5-difluorophenyl)-2-phenyl- 1.3,4-thiadiazol-3(2//)-yl)-2-mcthoxypropan- 1 - one. MS ESI (+) m/z 462 (M+l) detected; ¹ H NMR (400 MHz, CD ₃ OD) δ 7.65-7.60 (m, IH), 7.53- 7.47 (m, 2H), 7.43-7.37 (in, 2H), 7.35-7.27 (m, 3H), 4.854.79 (m. IH), 3.39-3.30 (m, 2H), 3.29 (s, 3H), 3.25-3.18 (m, IH), 2.63-2.53 (m, I H), 2.13-2.02 (m, IH), 1.62-1.51 (m, I H), 1.46 (d, 3H, J = 6.6 Hz).

Example 8

/y-(3-((.9)-5-(2.5-difluorophenyl)-3-((.S ^t )-2-methox\'propanoyl)-2-phenyl-2.3-dihvdro-1.3.4- thiadia/ol-2-yl)propyl)acetaιnidinc hydrochloride

[00204] To a solution of (5>l-((6)-2-(3-ajninoproρyl)-5-(2,5-diπuorophcnyl)-2-ph enyl-l _r 3,4- thiadiazol-3(2//)-yl)-2-mcthoxypropan- 1 -one (Example 5. Steps A-F; 57.5 mg, 0.1 17 mmol) and methyl acetimidatc hydrochloride (192 mg, 1.75 mmol) in methanol was added triethylamine (355 mg, 3.51 mmol). After heating at 5O ⁰ C for 16 hours, the mixture was concentrated under reduced

pressure. The residue was chromatographed (15 85: 1 MeOH/dichloromelhane/NHjOH), and the isolated material was treated with excess HCl in MeOH then concentrated to aflbrd the product. MS ESl (+) m/z 461 (M+ 1) detected; ¹ H NMR (400 MHx, CD ₃ OD) δ 7.65-7.60 (m, IH), 7.49-7.45 (m, 2H), 7.42-7.38 (m, 2H), 7.35-7.29 (m, 3H), 4.80 (q, IH, J = 7.1 Hλ), 3.50-3.40 (in, 2H), 3.36 (s, 3H), 3.28-3.19 (m, IH), 2.65-2.57 (m, IH), 2.22 (s, 3H), 2.21-2.12 (m, IH), 1.75-1.64 (m, IH), 1.44 (d, 3H. J = 7.1 Hz).

Example 9

λ^-(3-((/f)-5-(2,5-Difluorophcnyl)-3-((6V2-melhoxypropan oyl)-2-phcnyl-2.3-dihvdro-1.3.4- thiadiazol-2-yl)propyl)aeetamidine hydrochloride

[00205| Prepared according to the method of Example 8, using (.S)-l-((λ)-2-(3-aminopropyl)-

5-(2,5-diπuorophenyl)-2-phcnyl-l,3,4-thiadiazol-3(2W)-yl)-2 -inethoxyρropan-l-one (Example 7, Step A) in place of (.S)-l-((.S)-2-(3-aminopropyl)-5-(2.5-difluorophcnyl)-2-phen yl-l^,4-thiadiazol- 3(2W)-yl)-2-methoxypropan-l-onc, MS ESl (+) m/z 461 (M+I) detected; ¹ H NMR (400 MHz, CD _J OD) δ 7.66-7.60 (m, IH), 7.53-7.48 (m, 2H), 7.44-7.38 (m, 2H), 7.35-7.28 (m, 3H), 4.83 (q, I H, J = 6.9 Hz), 3.51-3.37 (in. 2H), 3.29 (s, 3H), 3.26-3 16 (m, IH), 269-2.60 (m, IH), 2.24 (s, 3H), 2.21-2.09 (m. IH), 1.68-1.57 (m, IH). 1.47 (d, 3H ₁ J= 6.9 Hz).

Example 10

2-Cvano-l-(3-(ffl-5-(2.5-difluoropheiiyl)-3-((.S>2-mctlio xypropanoyl)-2-phenyl-2.3-dilivdro-1.3.4- thiadia?:ol-2-vl ^" )propyO-3-methylguanidine

|002061 Prepared according to the method of Example 2, using niethan amine in place of ammonia and (.S)-l-((.S)-2-(3-aminopropyl)-5-(2.5-difluorophcnyl)-2-phen yI-l,3,4-thiadiazol-3(2//)- yl)-2-mclhoxypropan-l -onc (Example 5, Steps A-F) in place of (25>l -(2-(2-amiιioethyl)-5-(2,5- difluorophenyl)-2-plicnyl-l _J 3,4-lhiadia/x)l-3(2//)-yl)-2-mctJiox>propan-l-one. MS ESI (+) m/z 501 (M+l) detected; ¹ H NMR (400 MHz, CD ₃ OD) δ 7.64-7.60 (m, IH), 7.49-7.45 (m, 2H), 7.42-7.36 (m, 2H), 7.34-7.27 (m, 3H), 4.82-4.75 (m, IH), 3.50-3.38 (m, I H), 3.37 (s, 3H), 3.27-3.12 (m, IH), 2.81 (d, 3H, J = 24.7 Hz), 2.60-2.42 (nι, IH), 2.20-2.08 (m, IH), 2.17-2.07 (m, I H), 1.71-1.59 (ni, IHX 1.43 (d, 3H, J = 6.8 Hz).

Example 11

2-Cvano-l-(3-((/{)-5-(2.5-difluorophcnvπ-3-((ά')-2-meth owpropano\i)-2-phcnyl-2.3-dih\dro-1.3.4- thiadia/ol-2-yl)ρiOpyl)-3-mcthylguanidinc

[00207] Prepared according to lhc method of Example 2, using mcllumaniinc in place of ammonia and (S)- 1 -((/ϊ)-2-(3-aminopropyl}-5-(2,5-difluorophenyl)-2-phcnyl- 1 ,3,4-lhiadiazol-3(2//)- yl)-2-methoxyproρan-l-one (Example 7, Step A) in place of (2S)-l-(2-(2-aminoethyl)-5-(2,5- difluorophcnyi)-2-phcnyl-l,3,4-lhiadiazol-3(2//)-yl)-2-mctho xypropan-l-one. MS ESl (+) m/z 501 (M+l) detected: ¹ H NMR (400 MHz, CD ₃ OD) δ 7.64-7.59 (m, IH), 7.52-7.48 (m, 2H), 7.42-7.36 (m, 2H), 7.33-7.27 (m, 3H), 4.80 (q, IH, J = 7.0 Hz), 3.43-3.28 (m, 2H), 3.27 (s, 3H), 3.21-3.12 (m, IH), 2.78 (s, 3H), 2.55-2.46 (m, IH), 2.06-1.95 (m, IH), 1.64-1.53 (m, IH), 1.46 (d, 3H,7= 7.0 Hz).

Example 12

l-((5-(2.5-Difluorophenyl)-3-isobutyr\ l-2-pl]envi-2.3-dihvdro-1.3.4-thiadia/ol-2-vnmethvn-2- mcthoxyguanidinc hydrochloride

[00208J Step A: Preparation of l-mcthoxy-2,3-di-/g/y-butoxycarbonyl guanidinc: To a solution of A^-di-Boc-l/Z-pyrazolc-l-carboxainiditic (450 ing, 1.45 mmol) and mcthoxyainino hydrochloride (151 mg, 1.81 mmol) in THF (3 mL) and methanol (3 mL) was slowly added triethylamine (183 mg, 1.81 mmol). After stirring at room temperature for 64 hours, the reaction mixture was concentrated under reduced pressure and diluted with ethyl acetate. The salts were removed by filtration. The filtrate was concentrated under reduced pressure and triturated with ether to provide the crude product that was used without further purification.

(00209| Step B: Preparation of tert-butyl N-(/er/-butoxycarbonylWV'- niethoxycarbaininiidoyl(2-oxo-2-phenylethyl)carbainate: To a solution of crude l-methoxy-2,3-di- /<?rf-butoxycarbonyl guanidine (420 mg, 1.45 mmol) and bromoacetophcnonc (361 mg, 1.81 mmol) and potassium hydroxide (163 mg, 2.60 mmol) in dichloromcthanc and water ( 15 mL, 1 : 1) was added tclrabutylammonium iodide (54 mg, 0.145 mmol). After stirring at room temperature for 16 hours, the organic layer separated, dried (Na _∑ SO.*). and filtered. The filtrate was concentrated under reduced pressure, and the residue was chromatography (10% - 25% ethyl acetate in hcxancs) to provide the product in 60% purity, along with l -mcthoxy-2,3-di-/<?/7-butoxycarbonyl guanidine starting material.

[00210] Step C: nietlioxycarbamiιnidoyl( ^' (5-( ^' 2.5-difluorophenyπ-2-phei)yl-23-dihvdro-1.3.4-lhiadia/.ol-2 -vπmethvπ carbamate: To a solution of tert-butyl M{teτ/-butoxycarbonyl)-λ''-mcthoxycarbamimidoyl(2-oxo-2- phcnylcthyl)carbamatc (220 mg. 60% pure. 0.319 mmol) in cthanol (1 mL) was added 2,5- difluorobcnzothiohydrazidc (40 mg, 0.213 mmol). After stirring at room temperature for 16 hours, the mixture was concentrated under reduced pressure. Tire residue was chromatographcd (3% - 5% ethyl acetate in hexanes) and solidified under high vacuum to provide the product (68.5 mg, 56% yield) as a white solid.

J002111 Step D: Preparation of I -(ø-QJ-difluorophciivn-S-isobutyryl^-phcnyl-^J-dilivdro-

1.3.4-thiadia7θl-2-yl)methyl)-2-methoxyguanidine hydrochloride: To a solution of /e/7-bulyl λT-(tcrt- butoxycarbonyl)-λ ^π -inethoxycarbaniimidoyl((5-(2,5-difluorophenyl)-2-phenyl-2,3 -dihydro-1^3,4- lhiadiazol-2-yl)metliyl)carbamate (25.3 mg, 0.044 mmol) in dichloromethane (I mL) was added triethylamine (17.7 mg, 0.175 mmol) followed by isobutyryl chloride (14 mg, 0.131 mmol). After stirring at room temperature for 3 hours, the reaction mixture was concentrated under reduced pressure. The residue was chromatographcd (10% ethyl acetate in hcxancs) to provide the Boc- protccted product (23 nig. 81%) as a white foam. To this product was added HCl (1 mL of a 2M solution in dioxanc). After stirring at room temperature for 16 hours, the mixture was concentrated

under reduced pressure. The residue was triturated with ether to provide the product as a white powder and as a mixture of diastereomcrs (16.3 mg, 94% yield). MS ESI (+) m/z 448 (M+l) detected; ¹ H NMR (400 MHz, CDCl ₃ ) δ 7.56-7.50 (m, IH), 7.41-7.28 (m, 5H), 7.14-7.05 (m, 2H), 4.52-4.45 (m, IH), 3.65-3.52 (m, 1 H), 3.57 (br. s, 3H), 3.48 (q, IH, J = 6.2 Hz), 1.28 (d, 3H, J = 6.2 Hz), 1.22 (d, 3H, J = 6.2 Hz).

Example 13

l-((3-((.y)-5-(2.5-Difluorophcnyl)-3-((.S')-2-metlioxypropan oyl)-2-phenyl-2^-dihvdro- 1.3.4- thiadiazol-2-yl')propylamino)(methylamino)tnethylcnc')urca hydrochloride 1002121 To a solution of 2-cyano-l-(3-(0S>5-(2,5-difluorophcnyl)-3-((S)-2- inclhoxypropanoyl)-2-phcnyl-2,3-dihydro-l,3,4-thiadiazol-2-y l)propyl)-3-mcthylguanidinc (Example 10; 130 mg, 0.26 nimol) in methanol (3 mL) was added HCl (0.65 mL of a 4 M solution in dioxane) and water (0.05 mL, 2.6 nimol). After stirring al room temperature for 16 hours, the mixture was concentrated under reduced pressure. The residue was triturated with ether to provide the product as a pale pink solid (135 mg, 94% yield). MS ESl (+) m/z 541 (M+Na) detected; ¹ H NMR (400 MHz, CD ₃ OD) δ 7.66-7.61 (m, IH), 7.49-7.46 (in, 2H), 7.42-7.37 (m, 2H), 7.34-7.28 (m, 3H), 4.79 (q, IH, J = 6.4 Hz), 3.53-3.43 (m, 2H), 3.36 (s. 3H), 3.30-3.20 (m, IH), 2.95 (s, 3H), 2.67- 2.55 (m, IH), 2.23-2.1 1 (m, I H), 1.75-1.63 (m, IH), 1.43 (d, 3H,./= 6.4 Hz).

Example 14

3-(5-(2.5-Difluorophenyl)-3-((.y)-2-motlioxypropanoyl)-2- phenyl-2.3-dihvdro-I.3.4-thiadiazol-2- yiypropanimidamide hydrochloride

[00213| Step A: Preparation of 4-oxo-4-phenylbutancnitrile: To a solution of 3-cliloro-l- phenylpropan-1-one (5.0 g, 29.7 mmol) in hot cthanol (7 niL) was added potassium acetate (2.91 g. 29.77 mmol). After cooling to room temperature, the precipitated salt was removed via filtration. To the filtrate in a septum-sealed flask under a nitrogen bubbler was slowly added sodium cyanide (2.91 g, 59.3 mmol) as a solution in water (10 niL). After stirring at room temperature for 24 hours, elhanol (30 mL) was added, and the mixture was cooled in an ice bath. The precipitate was filtered and rinsed with cthanol to provide the product (3.42 g, 73%) as fluffy white solid. (00214J Step B: Preparation of 3-f5-(2,5-difluorophcnyl)-2-phcnyl-2.3-dihvdro-1.3.4- thiadiayol-2-yl)propancnitrilc: To a solution of 4-oxo-4-phcnylbutancnitrile (0.076 g, 0.48 mmol) in cthanol (5 mL) was added 2,5-difluorobcnzothiohydrazide (0.09 g, 0.48 mmol). After stirring at 9O ⁰ C for 16 hours, lhc reaction mixture was concentrated under reduced pressure. The residue was dissolved in ethyl acetate and washed with water and brine, dried over filtered and concentrated under reduced pressure. The residue was chromatographed (20% ethyl acetate in hcxancs) to provide the product (0.087 g, 55% yield).

[00215] Step C: Preparation of 3-(5-(2,5-difluorophcnyl)-3-((λV2-methoxypropanoyl)-2- phcnyl-2.3-dihvdro- 13.4-thiadiayol-2-yltøropaιicnitrilc: To a solution of 3-(5-(2,5-difluorophcnyl)- 2-phenyl-2,3-dihydro-l,3,4-thiadiazøl-2-yl)propanenitrile (0.398 g, 1.208 mmol) and (S)-2- niclhoxypropanoic acid (0.1 157 mL, 1.571 mmol) in DMF (40 mL) was added diisopropylethylamine (0.316 mL, 1.81 mmol) and PyBOP (1.26 g, 2.42 mmol). After stirring at room temperature for 28 hours, the mixture was diluted with saturated NaHCOj (100 mL) and extracted with ethyl acetate. The combined organics were washed with brine, dried over NajSOα, filtered and concentrated under reduced pressure. The residue was chromatographed (30% ethyl acetate in hexanes) to provide the product (0.431 g, 86% yield) as a brown syrup. [00216| Step D: Preparation of 3-(5-(2,5-difluorophenylV3-((.S')-2-methox\'propanoyl)-2- phenyl-23-dihvdro- 1.3.4-thiadiarol-2-yl)propaniinidaniidc h ^y drochloride: To a cooled (0 ^β C) solution of 3-(5-(2,5-difluorophenyl)-3-((»S)-2-metlioxypropano>l)-2 -phcnyl-2,3-dihydro- 1 ,3,4- lhiadiazol-2-yl)propancnilrile (0.053 g, 0.13 mmol) in cthanol (0.5 mL) was added a 9.8 M solution of cthanolic HCl (0.5 mL). After stirring at O ⁰ C for 10 minutes and then at room temperature for 4 hours, the reaction mixture was concentrated under reduced pressure. To the residue was added NH ₅ (1.0 mL, 7.0 mmol, 7 M solution in methanol). After stirring at room temperature for 30 minutes, the mixture was concentrated under reduced pressure. The residue was chromatographed (dichloromethane followed by 20% MeOH and 1% aqueous NH ₄ OH in dichloromctliane) to afford the product as a mixture of diastercomcrs (8.4 mg, 15% yield). MS ESI (+) rø/z 433 (M+l) detected; ¹ H NMR (400 MHz, CDCl ₃ ) δ 9.0 (br, 4H) ₁ 8.7 (br, 4H), 7.51 (in, 2H) ₈ 7.38 (m, 8H), 7.32 (m, 2H),

7.14 (m, 4H), 4.73 (ni, 2H), 3.57 (m, 2H), 3.42 (s, 3H), 3.35 (s, 3H), 2.75 (m, 4H), 2.33 (ni, IH), 2.23 (m, IH), 1.52 (d, 3H, J = 6.3 Hz), 1.48 (d, 3H, J = 7.0 Hz).

Example 15

3-(5-(2.5-Difluorophcnyl)-3-((.y)-2-mcthoxypropano>l)- 2-phenyl-2,3-dihvdro-l ,3.4-thiadia-/ol-2-yl)-

JV-mcthoxypropanim idani ide

[00217] To cooled (0 ⁰ C) solution of 3-(5-(2,5-difluorophenyl)-3-((S)-2-mcthoxypropanoyl)-

2-phenyl-2 ₅ 3-dihydro-l,3,4-thiadiazol-2-yl)propanenilrile (0.052 g, 0.13 liiniol, Example 14, Step C) in ctlianol (0.5 niL) was added 9.8 M ctlianolic HCl (0.5 niL, 4.9 mniol). After stirring at room temperature for 6 hours, the mixture was concentrated under reduced pressure. To the residue was added mcthoxylamine hydrochloride (0.021 g, 0.25 nimol). absolute cthanol (0.5 inL) and triethylaininc (0.087 mL, 0.63 mmol). After stirring at room temperature for 16 hours, the mixture was concentrated under reduced pressure. The residue was diluted with 10% Na;COj (30 in L) and extracted with dichloromcthane. The combined organics were dried, filtered and concentrated under reduced pressure. The residue was chromatographed (40% ethyl acetate in hexanes) to afford the product as a mixture of diastcrcomcrs (14 mg, 25% yield). MS ESI (+) m/z 463 (M+l) delected; ¹ H NMR (400 MHz, CDCl ₃ ) δ 7.50 (m, 2H), 7.38 (m, 8H), 7.30 (m, 2H), 7.13 (ni, 4H), 4.78 (q, IH, J = 6.3 Hz), 4.72 (q, IH, J = 6.3 Hz), 4.64 (br. s, 4H), 3.77 (s, 6H), 3.54 (m, 2H), 3.41 (s, 3H), 3.36 (s, 3H) ₅ 2.68 (m, 4H), 2.18 (m, 2H), 1.51 (d, 3H, J= 6.3 Hz), 1.49 (d, 3H, J = 7.0 Hz).

Example 16

3-(5-(2.5-Difluorophciiyl)-3-((5)-2-mclhoxypropaιioyl)-2 -phenyl-2,3-dilivdro-1.3.4-thiadiazol-2-ylV

/VO-fluorocthvOpropanimidamidc

(00218) Step A: Preparation of ethyl 3-(3-(2.5-difluorophenyl)-3-((.S1-2-nicthoxypropanoylV

2-phenyl-2.3-dihvdro-I.3.4-thiadiaxol-2-yl)propaniniidate hydrochloride: To a cooled (O ⁰ C) solution of 3-(5-(2.5-difluorophcnyl)-3-((S)-2-methoxypropanoyl)-2-pheny l-2 _? 3-dihydro-1.3,4-thiadiazol-2- yOpropanenitrile (0.041 g ₅ 0.099 mniol, Example 14, Step C) in ethanol (0.5 inL) was added 9.8 M ethanolic HCl (0.5 niL, 4,9 mtnol). After stirring at 0 ⁰ C for 1 hour and then at ambient temp for 8 hours, the mixture was concentrated under reduced pressure to provide the product. (00219| Step B: Preparation of 3-(5-(2.5-diπuorophenyl)-3-((,S')-2-mcthox\φropanoyl)-2- phem 1-2.3 -dilwdro-1.3.4-thiadiazol-2-yl)-Af-(2-ωuoroewyl)propanamidi ne: To a solution of ethyl 3- (5-(2,5-dilluorophenyl)-3-((λ')-2-methoxyρropanoyl)-2-phcn yl-2,3-dih> dro-l _r 3,4-thiadiazol-2- yOpropanimidate hydrochloride (0.022 g, 0.0442 nimol) in ethanol (0.5 niL) was added triethylamine (0.120ml. 0.861 mmol) and 2-fluoroethanamine hydrochloride (0.00440 g, 0.0442 mmol). After stirring at room temperature for 16 hours, die reaction mixture was concentrated, diluted with 10% NajCOj (30 inL) and extracted with dichloromelhanc. The combined organics were dried over Na2$θ4, filtered and concentrated. The residue was chromatographcd (10% methanol, 1% aqueous NR _t OH in dichloromethane) to afford the product as a mixture of diastcreomcrs (0.010 g, 47% y ield). MS ESl (+) Wz 479 (M+l) detected; ¹ H NMR (400 MHz, CDCl ₃ ) δ 7.50 (m, 2H), 7.38 (m, 8H), 7.31 (in, 2H), 7.14 (m, 4H), 4.794.70 (111, 2H), 4.65 (t, VAJ = 4.7 Hz), 4.53 (L 2H, J = 4.7 H/.), 3.58-3.45 (m, 6H), 3.42 (s, 3H), 3.36 (s, 3H), 2.84-2.71 (m, 4H), 2.36-2.18 (m. 2H), 1.52 (d, 3H _; J= 6.3 Hz). 1.48 (d, 3H, J = 7.0 Hz).

Example 17

3-(5-f2.5-Difluorophenyl)-3-((.'?)-2-mcthox\yrppaiio\'l)- 2-phenyl-2.3-dihvdro-1.3,4-thiadiazol-2-yl'>- yV-(2-methoxyethyl)propanimidamidc

|00220| Prepared according to the method of Example 16. using 2-mcthoχycthanamine in place of 2-fluoroethananiine to afford the product as a mixture of diastcreomcrs. MS ESl (+) m/z 491 (M+l) detected; ¹ H NMR (400 MHz, CDC! ₃ )8 7.51 (m, 2H) ₅ 7.42-7.29 (m, 8H), 7.31 (m, 2H), 7.14 (m, 4H), 4.78-4.69 (m, 2H), 3.58-3.50 (m, 6H), 3.42 (s, 3H), 3.36 (m, 13H), 2.82-2.68 (m, 4H), 2.31-2.13 (m, 2H), 1.52 (d, 3H, J = 7.0 Hz), 1.48 (d, 3H, J = 7.0 Hz).

IV)- 1 -((,S>2-(2-( Aminooxy)cthyl)-5-(2,5-diπuorophcnyl)-2-phonyl- 1 ,3.4-lhiadia/.ol-3(2#)-yl)-2- methoxypropan-l-oiic hydrochloride

[00221] Step A: Preparation of fer/-butyl 3-oxo-3-phcnylpropoxycarbamate: To a cooled

(0 ⁰ C) solution of /er/-butyl hydroxycarbamate (1.90 g, 14.2 mmol) in THF (30 niL) was added NaH (0.285 g, 11.9 mmol). Afler stirring at O ⁰ C for 5 minutes and at room temperature for 10 minutes, the mixture was added to a solution of 3-chloro-I-phenylpropan-l-one (2.00 g, 11.9 mmol) in THF (10 mL). After stirring at room temperature for 30 minutes, the mixture was filtered, and the filtrate was concentrated under reduced pressure. The residue was chromatographcd (20% ethyl acetate in hcxanes) to provide the product (2.20 g, 69%) as a white solid.

[00222 J Step B: Preparation of /<?r/-butyl 2-(5-f2.5-difiuorophenyl)-2-phcnyl-2.3-dihvdro- l.3.4-thiadiazol-2-yl)cthoxycarbamatc: A mixture of /erf-butyl 3-oxo-3-phcnylpropoxycarbamatc (1.09 g, 4.10 mmol) and 2,5-difluorobenzothiohydrazidc (0.515 g, 2.74 mmol) in cthanol (3 niL) were stirred together at room temperature for 16 hours. The reaction mixture was concentrated under reduced pressure. The residue was chromatographcd (20% ethyl acetate in hexancs) to provide the product as a white solid (0.94 g, 79% yield).

[00223| Step C: Preparation of (S)-I -((λV242-(aminooxy)cthv])-5-(2.5-difluorophenyl)-2- phcnyl- 1.3.4-thiadia/ol-3(2//)-yl)-2-inethoxypropan- 1 -one hydrochloride: To a solution of (ert-buly\ 2-(5-(2,5-difiuorophenyl)-2-phcnyl-2.3-dihydro- 1,3 ,4-thiadiazol-2-yl)clhox\ carbamate (0.340, 0.781 mmol) in DMF/dichloromethane (1:1, 2 niL) was added (S)-2-methoxypropanoic acid (0.122, 1.17 mmol), l -(3-dimcthylaminopropyl)-3-ethylcarbodiimidc hydrochloride (0.299 g, 1.56 mmol). HOBt (0.21 1 g, 1.56 mmol), and tricthylaminc (0.33 niL, 2.34 mmol). After stirring at room temperature for 16 hours, the mixture was partitioned between IN HCl and ethyl acetate. The organic layer was washed with water and brine, dried over Na^SO,, filtered and concentrated under reduced pressure. The residue was chromatographcd (30% ethyl acetate in hcxanes) to provide the diastcrcomcrically enriched (9: 1 S.S.S.R diastercomer ratio) Boc-protccted product (35 mg. 9% yield). To this product was added a solution of HCl in dioxanc (4M, ImL). After stirring at room temperature for 4 hours, the mixture was concentrated under reduced pressure and triturated with diethyl ether to provide the product as a white solid (0.025 g, 81% yield). MS ESI (+) m/z 444 (M+Na) detected; ¹ H NMR (400

MHz, CD ₃ OD) δ 7.68-7.63 (m, IH), 7.48-7.46 (m ₅ 2H), 7.44-7.38 (m, 2H), 7.36-7.30 (ni, 3H), 4.76 (q, IH, ./ = 7.2 Hz), 4.54-4.48 (m, IH), 4.43-4.36 (m, IH), 3.67-3.59 (ni, IH), 3.33 (s, 3H), 3.05-2.97 (m, IH), 1.43 (d, 3H, J= 7.2 Hz).

Example 19

1-(2-((λV5-f2.5-Difluorophcnyl)-3-f(.S')-2-ιncthoxyprop anovn-2-phcnyl-2.3-dihvdro-1.3.4- thiadiazol-2-vDethoxykuanidine hydrochloride

[00224] To a solution of ($>l-((,S)-2-(2-(aminooxy)ethyl)-5-(2,5-dinuorophcnyl)-2- phcnyl-

1.3,4-thiadiazol-3(2//)-yl)-2-mclhoxypropan-l-one hydrochloride (Example 18; 11.1 mg, 0.024 mmol) dissolved in THF was added tricthylaniine (25 μL, 0.18 mmol) and /V^V-di-Boc-l//-pyrazolc- I-carboxainidinc (0.025 g, 0.081 mmol). After stirring at room temperature for 16 hours, the mixture was concentrated under reduced pressure. The residue was chromatographcd (20% ethyl acetate in hεxanes) to provide the Boc-protected product (9 mg, 56%). To this material was added a solution of HCl in dioxanc (4M, 1 niL). After stirring at room temperature for 16 hours, the mixture was concentrated under reduced pressure and triturated with diethyl ether to provide the product as a white solid (6 mg, 89% yield). MS ESl (+) m/z 464 (M+l) detected; ¹ H NMR (400 MHz, CD ₃ OD) δ 7.67-7.62 (in,. IH), 7.49-7.45 (m, 2H), 7.44-7.38 (m, 2H), 7.36-7.30 (m, 3H), 4.76 (q, IH, J = 7.2 Hz), 4.41-4.34 (m, IH), 4.23-4.17 (m, IH), 3.68-3.62 (m, IH), 3.35 (s, 3H) ₅ 3.02-2.94 (m, IH), 1.43 (d, 3H, .7= 7.2 Hz).

Example 20

l-(2-(5-(2.5-Difluorophenyl)-3-((.S')-2-methoxypropanoyl)-2- phenyl-2.3-dihvdro-1.3.4-thiadiazol-2- vDethylVl-methoxyguanidine hydrochloride

[00225| Step A: To a solution of Boc-anliydride

(12.0 g, 55.0 mmol) in dichloromcthanc (100 niL) was added a solution of sodium carbonate (17.5 g, in 100 mL water). To this mixture was added dropwisc a solution of methoxyamine hydrochloride (13.8 g, 165 mmol) in water (100 mL). After stirring at room temperature for 18 hours, the organic layer was washed with water, dried over Na ₂ SO.*, filtered and concentrated under reduced pressure to provide the product (7.94 g, 98% yield) as a clear oil.

[00226] Step B: Preparation of tert-baixl methoxy(3-oxo-3-phcny]propyl)carbamate: To a cooled (O ⁰ C) solution of tert-butvl mcthoxycarbamatc (2.35 g, 16.0 mmol) in THF (50 mL) was slowly added NaH (0.640 g, 16.0 mmol). After stirring at 0 ⁰ C for 5 minutes and then at room temperature for 30 minutes, the mixture was added dropwisc to a solution of 3-chloro-l- phenylpropan-1-onc (2.84 g, 16.8 mmol) in THF (25 mL). After stirring at room temperature for 30 minutes, the mixture was filtered and the filtrate was concentrated under reduced pressure. The residue was chromatographcd (10% ethyl acetate in hexancs) to provide the product (1.80 g, 40% yield) as a clear oil.

[00227J Step C: Preparation of terλbutyl 2-(5-(2.5-difluorophenyl)-2-phenyl-2,3-dihvdro- l .3.4-thiadiayol-2-vDethyl(ιnethoxy)carbainate: A mixture of 2,5-difluorobcn/otliiohydra/ide (0.500 g. 2.66 mmol) and tert-bulyl nicthoxy(3-oxo-3-phcn> lpropyl)carbamate (1.11 g, 3.99 mmol) was stirred together in ethanol (5 mL) for 30 hours. The reaction mixture was concentrated under reduced pressure, and the residue was chromatographed (20% ethyl acetate in hexancs) to provide the product (0.650 g, 1.45 mmol) that was used in the next step without further purification. (00228) Step D: Preparation of (2.y)-l-(5-(2.5-difluorophenyl)-2-(2-(ιnetlιoxyamiιio)cth vn-2- phenyl-13.4-thiadiazol-3(2//)-yl)-2-methoxypropan-l-onc h ^y drochloride: To a solution of (S)-2- mcthoxyprøpanoic acid (0.226, 2.17 mmol) in DMF (3 mL) was added diisopropylcthylaminc (0.50 mL, 2.89 mmol) and PyBOP (1.13 g, 2.17 mmol). After stirring at room temperature for 5 minutes, the mixture was added to lerl-bulyl 2-(5-(2,5-difJuorophcnyl)-2-phenyl-2.3-dihydro-l,3,4-thiadia zol- 2-yl)cthyl(methoxy)carbanialc (0.650 g, 1.45 mmol). After stirring at room temperature for 4 hours, die mixture was partitioned between saturated NaHCOj and ethyl acetate. The organic layer was washed with water and brine, dried over NajSO.*, filtered and concentrated under reduced pressure. The residue was chromatographcd (15% ethyl acetate in hexancs) to provide the Boc-protcctcd product (0.490 g, 63% yield) as a white foam. To this material was added HCI in dioxane (4 mL of a 4 M solution). After stirring at room temperature for 2 hours, the mixture was concentrated under reduced pressure and triturated with hcxanes to provide the product as a white solid and as a mixture of diastereomcrs (0.21 1 g, 92% yield).

[00229] Step E: Preparation of l-(2-(5-(2.5-difluorophenyl)-3-((,S')-2-methoxypropaιioyl)- 2- phenyl-23 -dihvdro-1.3.4-thiadiazol-2-yl)cthvO-l-metlioxyguanidine hydrochloride: To a solution of

(25>H5-(2p-dil1uorophenyl)-2-(2-(methox>'amiiio)ethyl) -2-phcnyl-U,4-tl»iadiazol-3(2W)-j'l)-2- nicthoxypropan-1-onc hydrochloride (50 mg. 0.11 mmol) in THF (1 niL) was added NEt ₃ (240 μL, 1.7 ramol) and vVj/V-di-Boc-l/Z-pyrazole-l-carboxamidine (260 mg, 0.85 mmol). The reaction mixture was stirred at room temperature for 1 week then concentrated. The residue was suspended in a 25% EtOAc in hcxancs solution (5 mL), filtered, and the filtrate was concentrated. Purification of the residue by flash chromatography (25% EtOAc in hcxancs) afforded the di-Boc protected product as a white solid (45 mg, 63% yield). To this material was added a solution of HCl in dioxanc (1 mL of a 4M solution), and the mixture was stirred at room temperature for 48 hours. The mixture was then concentrated, and the residue was triturated with EtiO to afibrd the product as a white solid and as a mixture of diastcrcomcrs (30 mg, 88% yield). MS ESI (+) m/z 478 (M+H) detected; ¹ H NMR (400 MHz. CD ₃ OD) δ 7.64-7.69 (m, 2H), 7.50-7.44 (m, 4H), 7.44-7.38 (m, 4H), 7.36-7.29 (m, 6H), 4.86-4.77 (m, 2H), 4.25-4.14 (m, 2H), 3.84-3.75 (m, IH), 3.77 (s, 3H), 3.76 (s, 3H), 3.74-3.64 (m, IH), 3.59-3.50 (m. 2H), 3.40 (s, 3H), 3.29 (s, 3H), 3.06-2.96 (m, 2H), 1.50 (d, 3H. y = 6.5 Hz). 1.43 (d, 3H, ./ = 6.5 Hz).

Example 21

2-(2-(5-(2.5-Dinuoroplienyl)-3-(ffl-2-nicthoxypropanoylV2-ph enyl-2.3-dihvdro-1.3.4-thiadiazol-2- y DethvPhvdrazinecarboxim idamide hydrochloride

(00230] Step A: Preparation of //JV-di-Boc-3-hvdrazinyl-l-Dheiiylpropan-l-one: To a cooled

(0 ⁰ C) solution of di-Boc-hydrazine (2.0 g, 8 6 mmol) in THF (30 mL) was slowly added sodium hydride (210 nig, 8.6 mmol). After stirring at O ⁰ C for 5 minutes and then at room temperature for 30 minutes, the mixture was added to a solution of S-chloro-l-phcnylpropan-l-onc (1.50 g, 8.6 mmol) in THF (10 mL) After stirring at room temperature for 30 minutes, water was added, and the mixture was partitioned between brine and ethyl acetate. The organic layer was dried over NajSO.j, filtered and concentrated under reduced pressure. The residue was chromatographed (15% ethyl acetate in hexancs) to provide the crude product.

(00231 | Step B: Preparation of di-Boc- 1 -(2-(5-(2.5-diπuorophcnλ lV2-plicnvi-2.3-dihvdro- l,3.4-thiadiazol-2-v0clhyl)hvdra/inc: A mixture of /V/^-di-Boc-S-hydrazinyl-l -phcnylpropan-l -one (0.868 g, 2.38 mmol) and 2,5-difluorobenzothiohydrazidc (0.265 g. 1.41 mmol) in ethanol (3 mL)

was stirred at room temperature for 3 days. The reaction mixture was concentrated under reduced pressure, and the residue was chromatographcd (35% ethyl acetate in hcxancs) to provide the crude product as a yellow foam.

(00232 j Step C: Preparation of (2.SVl -(5-(2.5-difiuorophcnyl)-2-(2-hvdrazinylcthyl)-2- phenyl- 13.4-thiadiazol-3(2/f)-yl ^' )-2-methoxypropan- 1 -one hydrochloride: To a solution of (S)-2- methoxypropanoic acid (0.146, 1.40 mmol) in DMF (4 mL) was added diisopropylethylamine (0.33 inL, 1.87 inmol) and Pv BOP (0.730 g, 1,40 mmol). After stirring at room temperature for 5 minutes, the mixture was added to di-Boc-l-(2-(5-(2 _! 5-difluorophenyl)-2-phcnyl-2,3-dihydro-l ,3,4- thiadiazol-2-yl)ethyl)hydrazine (0.500 g, 0.934 mmol). After stirring at room temperature for 4 hours, the mixture was partitioned between saturated NaHCO? and ethyl acetate. The organic layer was washed with water and brine, dried over Na ₃ SO ₄ , filtered and concentrated under reduced pressure. The residue was chromatographcd (20% ethyl acetate in hcxancs) to provide the Boc- protcctcd product (0.31 1 g. 54% yield). To this product was added HCl (4 mL of 4N solution in dioxane). After stirring at room temperature for 28 hours, the mixture was concentrated under reduced pressure and triturated with diethyl ether to provide the product as a yellow powder and as a mixture of diastercomcrs (0.125 g, 94% yield).

(00233) Step D: Preparation of 2-(2-(5-(2.5-difluorophenyl)-3-((,S')-2-mcthoxypropanoyl)-2- phenyl-2.3-dihvdro- 1.3.4-thiadia/ol-2-yl)eUw0hvdra7inecarboximidamide h ^y drochloride: To a solution of (2,S> 1 -(5-(2,5-difluorophenyl)-2-(2-hydrazinylethyl)-2-phenyI- 1 ,3,4-thiadiazol-3(2//)- yl)-2-methoxyρropan-l-one hydrochloride (40 ing. 0.088 mmol) in THF (1 mL) was added triethylamine (27 μL, 0.19 mmol) and A^V ^' -di-Boc-l/Z-pyrazolc-l-carboxamidine (30 mg, 0.096 mmol). The reaction mixture was stirred at room temperature for 1 hour then concentrated. The residue was purified by flash chromatography (20% EtOAc in hcxancs) to afford the di-Boc protected product as a white solid (30 mg, 52% yield). A solution of HCI in dioxane (4 mL of a 4M solution) was added to this material, and the reaction mixture was stirred at room temperature for 16 hours then concentrated. The residue was purified by flash chromatography (10-20% MeOH in CH ₂ Cb with 1% NH ₄ OH), and the isolated material was treated with excess HCl in McOH then concentrated to afford the product as a mixture of diastercomcrs (6.0 mg, 27% yield). MS ESI (+) m/z 463 (M+l) detected; ¹ H NMR (400 MHz, CD ₃ OD) δ 7.66-7.61 (m, 2H) ₅ 7.51-7.44 (m, 4H), 7.43-7.37 (m. 4H), 7.36-7.29 (m, 6H) ₅ 4.86-4.77 (m, 2H) _: 3.66-3.47 (m, 4H), 3.37 (s, 3H), 3.28 (s, 3H). 2.96-2.70 (m, 4H), 1.46 (d, 3H ₅ J= 6.8 Hz), 1.42 (d, 3H, J = 6.8 Hz).

/V-O-fffl-S-fσ.S-DiπuorophcnvD-S-ff^-l-mcthoxypropanovD-l- phcnyl-Z.S-dihvdro- 1.3.4- thiadiazol-2-yl)propyl)-2-fluoroacetimidamide

(00234) To a solution of (S>l-((S)-2-(3-aminopropyl)-5-(2,5-difluorophenyl)-2-phen yl-l,3,4- thiadia2θl-3(2H)-yl)-2-incthoxypropan-l-onc (Example 5, Steps A-F; 24.3 ing. 0.049 mmol) and cthyiriuoroacctimidc hydrochloride (69.9 mg, 0.493 mmol, ./. Med. Chan. 1990, 33(1 1 ), 3060-3067) in cthanol (0.5 mL) was added lriethylamine (0.138 niL, 0.987 mmol). After stirring at room temperature for 23 hours, the reaction mixture was concentrated, diluted with 10% NajCOj (30 mL) and extracted with dichloromctliane. The combined organics were dried ovcr Na;SO4, filtered, and concentrated under reduced pressure. The residue was chroniatographod (5% methanol, 0.7% aqueous NH ₄ OH in dichloroniethane) to afford the product as a yellow film (9.8 mg, 42% yield). MS ESI (+) m/z 479 (M+l) detected; ¹ H NMR (400 MHz, CDCI ₃ ) 8 7.51 (m, IH), 7.41 (m, 2H), 7.36 (ni, 2H), 7.29 (m, 1 H) _: 7.13 (m _: 2H), 4.96 (br s, 1 H), 4.84 (br s, 1 H), 4.69 (m, IH), 3.39 (s _; 3H), 3.32 (m, 3H), 2.49 (m, I H).2.17 (m. IH), 1.70 (m, IH), 1.47 (d, 3H, J = 7.0 Hz).

Example 23

2-((5-(2.5-Difluoroρhenyl)-3-((S)-2-mcthoxyproρanovD-2- phenvI-2.3-dihvdro-l .3.4-thiadiay.ol-2- yl)iiiethoxy)acetimidatnide

[00235] Step A: Preparation of 2-(2-oxo-2-phenylethoxy)acetic acid: To l,4-dioxanc-2,6- dione (1.Og, 8.6 mmol) (Aldrich, 90%) ύi 17 mL benzene was added aluminum(III) chloride (3.4 g, 26 mmol). The reaction mixture was heated at 60 ⁰ C for 2 hours and then at reflux for 1 hour. The reaction mixture was poured onto 2Og of ice in 20 mL of concentrated HCl. This mixture was stirred for 1 hour and then extracted with EtOAc. The combined organics were washed with brine, dried (MgSO ₄ ), filtered, and concentrated. Purification of the residue by silica gel chromatography (10% EtOAc in hexanes to 2% HOAc in EtOAc) provided 0.95 g of a brown syrup that contained the desired product as the primary component. This mixture was used in the subsequent step without further purification.

[00236| Step B: Preparation of 2-(2-oxo-2-phenylethoxy)acetam ide: To (he mixture from step

A (0.95 g) in 5 mL DCM at O ⁰ C was added DMF (0.0129 ml, 0.166 nimol) and then a solution of oxalyj chloride (0.640 ml, 7.34 tntnol) in 5 mL of dichloromcthanc. The ice bath was removed, and the reaction mixture was stirred at room temperature for 2.5 hours. The reaction mixture was then concentrated to afford 1.1 Ig of crude acid chloride as a dark red syrup. This residue was dissolved in THF (20 mL) and cooled to -78 ⁰ C. Ammonia gas was bubbled through the reaction solution for 5 minutes. The cold bath was removed, and the reaction mixture was stirred at ambient temperature for 2 hours. The reaction mixture was then concentrated, diluted with 10% Na^CC^ and extracted with ElOλc. The combined organ ics were dried (NasSQt), filtered and concentrated. Purification of the crude product by silica gel chromatography (10% MeOH, 0.7% aq NH ₄ OH in dichloromcthanc,) provided 0.281 g of an orange-brown solid that consisted of two compounds with the primary component being the desired product. This mixture was used in the subsequent step without further purification.

[00237J Step C: Preparation of 2-(2-oxo-2-phonylcthoxy)acetonitrile: To the mixture from step B (0.100 g) in pyridine (0.60 ml) at 0 ⁰ C was added TFAA (0.1097 ml, 0.7764 mmol). The reaction mixture was stirred for 3 hours and then concentrated. The residue was diluted with I M KHSO4 (30 mL) and extracted with EtOAc. The combined organics were washed with brine, dried (Na_SO<t) filtered and concentrated. Purification of the residue by silica gel chromatography (10% EtOAc in hexanes) afforded 69.5 nig of a light red-tinted oil that contained the desired product as the primary component. This mixture was used in the subsequent step without further purification. (002381 Step D: Preparation of 2-((5-(2,5-difluorophenvn-2-phenyl-2.3-dihvdro-l .3.4- thiadiazol-2-yl ^' hncthoxy'lacctonitrilc: To 2,5-difluoroben/X)thiohydrazidc hydrochloride (0.0885 g, 0.394 mmol) and the crude mixture from Step C (0.069 g) was added potassium acetate (0.0387 g. 0.394 mmol) in EtOH (0.7mL). The reaction mixture was stirred at room temperature for 16 hours. The reaction mixture was diluted with dichlorometliane (3 mL) and filtered. The filtrate was concentrated, and the crude material was purified by column chromatography (10% EtOAc in hexanes) to afford 97 mg of a colorless oil that contained the desired product as the primary component. This mixture was used in the subsequent step without further purification. (00239| Step E: Preparation of 2-((5-(2,5-difluorophem l)-3-((S)-2-ιncthoxypropanoyl)-2- pheιiv]-2.3-dihvdro-1.3.4-tliiadia/ol-2-yl)methoxy)acetonit rile: To a solution of HATU (0.0776 g, 0.2041 mmol) in 0.5 mL of DMF was added (S)-2-mcthoxypropanoic acid (0.0150 ml, 0.2041 mmol) and DIEA (0.071 1 ml, 0.4083 mmol) This mixture was stirred at room temperature for 10 minutes and the crude mixture from Step D (0.047 g) was then added followed by 0.2 mL of DMF. The reaction mixture was stirred at room temperature for 40 hours. The reaction mixture was diluted with saturated NaHCO.* and extracted with EtOAc. The combined organics were washed with brine,

dried (Na^SOα), filtered and concentrated. Purification of the residue by silica gel chromatography (20% EtOAc in hcxancs) provided 3.5 mg of a cloudy film that contained the desired product as the primary component. This mixture was used in the subsequent step without further purification. (0024Oj Step F: Preparation of 2-((5-(2.5-difluorophcnyl)-3-((S)-2-methoxypropanoyl)-2- phenyl-23-dihvdro-1.3.4-thiadiazol-2-yl)niethoxy)acetimidami de: To a solution of the mixture from Step E (.0035 g) in 0.5 niL of EtOH at 0 ⁰ C was added 9.8 M ethanoHc HCl (0.50 ml, 4.9 mniol). The reaction mixture was stirred at 0 ⁰ C for 90 minutes and then at room temperature for 1 hour. The reaction mixture was concentrated to afford 4.2 mg of the crude ethyl imidatc. To this residue was added 7 M ammonia in methanol (1 inL). The reaction mixture was stirred at room temperature for 3 hours and then concentrated. The residue was purified by silica gel chromatography (CH2CI2 - 10% MeOH in CH ₂ Cb - 10% MeOH, 2% concentrated aq NR ₄ OH in CH ₂ Cl;) to afford 1.3 mg of 2- ((5-(2,5-difluorophcnyl)-3-((S)-2-mcthoxj'propanoyl)-2-phcny l-2,3-dihydro-l,3,4-thiadiazol-2- yl)mcthoxy)acctamidtne as a mixture of diastcrcomcrs. MS ESI (+) mlz 449 (M+l) detected; ¹ H NMR (400 MHz, 20:1 CDCl ₃ CD ₃ OD) δ 7.52 (m, 2H), 7.41 -7.30 (m, 10H), 7.18-7. I l (m, 4H), 4.93 (nt 2H), 4.77-4.70 (m, 2H), 4.66-4.52 (m, 4H), 4.38 (in, 2H) ₅ 3.40 (s, 3H), 3.36 (s, 3H), 1.47-1.44(m, 6H).

Example 24

(ZV2-Cvano-l-(3-(5-(2.5-difluorop1ienyl)-3-isobutyr\ l-2-phenyl-2.3-dihvdro-1.3.4-thiadiazol-2- vI)propy0-3-mcthylguanidino

[00241J Step A: Preparation of l-(2-(3-a/idopropyl)-5-(2.5-difluorophcnyl)-2-phcnyl- 1.3.4- thiadiazol-3(2HVylV2-methylpropan-l-one: 2-(3-azidopropyl)-5-(2,5-difluorophenyl)-2-pheny1-2,3- dihydro-l,3,4-ιhiadiazole (100 mg, 0.278 mmol, Example 5, Step B) was weighed into a flask and dissolved in 5.0 mL of CH ₂ CK. Triethylaminc (0.058 ml, 0.417 mmol) was then added, followed by isobulyryl chloride (35.5766 mg, 0.333893 mmol). The reaction was then allowed to slowly warm to ambient temperature overnight. The reaction was then concentrated in vacuo, then loaded direct to biotagc (less pink precipitate), then purified by flash column chromatography (10 % ethyl acetate/Hexanes), yielding the desired product l-(2-(3-azidoproρyl)-5-(2,5-difluorophenyl)-2- phcnyl-l,3,4-thiadiazol-3(2H)-yl)-2-mcthylpropan-l-onc (94 mg, 78%).

[00242] Step B: Preparation of 1 -(2-(3-(amino)propyl)-5-f2.5-difluorophcnyl'>-2-phcιiyl-

1.3.4-thiadiazol-3(2H)-vD-2-methylpropan-l-onc: l-(2-(3-azidopropyl)-5-(2,5-difluorophenyl)-2-

phenyl-l ,3,4-thiadiazol-3(2H)-yl)-2-niethylpropan-l-onc (94 nig, 0.21 mmol) was weighed into a 25 mL I neck round bottom, and dissolved in 7 mL of McOH-HCl (0.547 ml, 1.094 mmol) and Pd/C (23 nig, 0.021 mmol) were then added. The reaction was stirred al ambient temperature and under an atmosphere of H ₂ for 45 minutes. The reaction was then concentrated affording the desired product (92.7 mg.96%).

(002431 Step C: Preparation of (ZV2-cvano-l -(3-(5-(2.5-difluorophenylV3-isobutyryl-2- phcnyl-2.3-dihvdro-1.3.4-thiadiaxol-2-\i)propyl)-3-mcthyleua nidinc: I-(2-(3-aininopropyl)-5-(2,5- difluorophenyl)-2-phen\i-l,3,4-thiadiazol-3(2H)-yl)-2-methyl propan-l-onc (66 nig, 0.163 mmol) was weighed into a 25 mL I neck round bottom flask, then dissolved in 2.0 mL IPλ. Tricthylamine (0.057 ml, 0.41 mmol) was then added followed by diphcnyl cyanocarbonimidate (78 mg, 0.327 mmol). The reaction was stirred at 23 ⁰ C for 1.5 hours. The reaction was then transferred to a pressure tube (20 mL), followed by addition of 3 mL of methyl amine (2.4 nil, 4.9 mmol) in McOH. The reaction was then placed in a 6O ⁰ C bath for 12 hours. The reaction was then removed and concentrated, and purified by flash column chromatography (3 -7 % McOH/DCM) to provide die desired product (41 mg, 52%) as a tan film. MS ESl (+) m/z 485 (M+E) detected; ¹ H NMR (400 MHz ₅ MeOH) 6 7.61 (m, IH), 7.45 (d, J = 7.8 Hz, 2H), 7.38 (m. 2H), 7.28 (m, 3H), 3.57 (m, IH), 3.35 (m, 2H), 3.13 (in, IH), 2.77 (s, 3H), 2.45 (m, IH), 2.08 (m, IH), 1.61 (m, IH), 1 19 (d, 3H. J = 6.2 Hz), 1.16 (d, 3H, ./= 7.2 H/).

Example 25

(Z)-2-Cvano-l-(3-(5-(2,5-difluorophcnyl ^' )-2-phcnyl-3-ρivaloyl-23-dihvdro-l _y 3.4-thiadia/ol-2- vPpropyO-3-niethylguanidinc

(002441 Step A: Preparation of 1 -(2-(3-azidopropyl)-5-(2.5-difluorophcnyl)-2-pheιiyl-l .3.4- thiadiay _J ol-3(2H)-vπ-2.2-dimcthylpropan-l-onc: 2-(3-azidopropyl)-5-(2,5-diπuorophcny])-2-phcny]- 2,3-dihydro-l,3.4-thiadiazole (100 mg, 0.278 mmol. Example 5, Step B) was weighed into a flask and dissolved in 5.0 mL of CHjCl ₂ . Triethylaininc (0.0581 ml, 0.417 mmol) was then added, followed by pivaloyl chloride (40.2 mg, 0.333 mmol). The reaction was then allowed Io slowly warm to ambient temperature over 12 hours. The reaction was concentrated and purified by flash column chromatography (10 % ethyl acetate/Hexancs) affording the desired product (100 mg, 81%).

|00245| Step B: Preparation of H2-(3-aminoproov1Kv(2.5-difluorophenyl)-2-phenyl-1.3.4- thiadiazol-3(2H)-yl)-2.2-diniethylpropan-l-one hydrochloride: l-(2-(3-azidopropyi)-5-(2,5- difluorophcnyl)-2 -phenyl- 1 _y 3,4-thiadiazol-3(2H)-yl)-2,2-dimcth> Ipropan- 1 -one ( 100 mg, 0.2255 niniol) was weighed into a flask and dissolved in 7 inL of McOH.HCl (0.563 nil, 1.12 mmol) and Pd/C (23 nig. 0.22 mmol) were then added. The reaction was stirred at ambient temperature under an atmosphere of H ₂ for 45 minutes. The reaction was then concentrated affording the desired product (97.4 mg, 95%).

[00246] Step C: Preparation of (Z)-2-cvaiio-l-(3-(5-(2.5-difltiorophcnyl)-2-phcnyl-3- pivaloyl-2.3-dihvdro-l.3.4-thiadia2θl-2-yl')propyl)-3-incth ylguaιiidinc: l-(2-(3-aininopropyl)-5-<2,5- difluorophenyl)-2-phcnyl-l ,3,4-thiadiazol-3(2H)-yl)-2,2-dimcthylpropan-l -one (66 mg. 0.158 mmol) was weighed into a flask, then dissolved in 2.0 mL IPA. Triethylamine (0.055 ml, 0.38 mmol) was then added followed by diphenyl cyanocarboniniidate (75 mg, 0.316 mmol). The reaction was then stirred at room temperature for 1.5 hours. The reaction was then transferred to a scaled tube, followed by addition of 3 mL of methyl amine (2.4 ml, 4.9 mmol) in McOH. The reaction was then placed in a 6O ⁰ C bath for 12 hours. The reaction was then removed and concentrated, and the residue was purified by flash column chromatography (3 -7 % McOH/ CH ₂ CN) to provide the desired product (32 mg, 41%) as a light orange foam film. MS ESl (+) m/z 499 (M+E) detected; ¹ H NMR (400 MHz, McOH) δ 7.48 (m, IH). 7.44 (d, J - 8.0 H/, 2H), 7.38 (m, 2H), 7.28 (m, 3H), 3.45 (m, IH) ₅ 3.39 (m, IH), 3.27 (m, IH), 2.78 (s, 3H), 2.45 (m, IH), 1.99 (m, I H), 1.59 (m, I H) ₅ 1.39 (s _s 9H).

Example 26

(Z)-2-(3-(2-Cvano-3-methylμuanidino)propyl)-5-f2.5-diflu orophenylVN-methoxλ'-N-methyl-2- plienv I- 1.3.4-thiadiazole-3(2 H)-carboxam ide

[00247] Step A: Preparation of (ZV2-(3-(2-cvano-3-mcthylguanidino)propyD-5-(2.5- difluoroρhcnvD-N-mcthoxy-N-mcthyl-2-ρhcnyl-1.3.4-lhiadia/o lc-3(2H)-carboxamidc: 2-(3- aminopropyl)-5-(2,5-difluorophenyl)-N-niethoxj'-N-mcthyl-2-p henyl-J,3,4-thJadiazoIc-3(2H)- carboxamide (61 mg, 0.145 mmol, prepared as described in WO 2006/044825 Example 121) was weighed into a flask, then dissolved in 2.0 mL IPA. Tricthylamine (0.051 ml, 0.362 mmol) was then added, followed by diphenyl cyanocarboniniidate (69 mg, 0.290 mmol). The reaction was stirrcd at

23 ⁰ C for 1.5 hours, then transferred to a pressure tube,, followed by addition of 3 niL of methyl amine (2.4 ml, 4.9 mmol) in McOH. The reaction was then placed in a 60 ⁰ C bath for 12 hours and then concentrated. The residue was purified by flash column chromatography (3 -7 % McOH/DCM) affording the desired product (27 nig, 37%) as an orange foam film. MS ESl (+) tπ/z 502 (M+E) detected; ¹ H NMR (400 MHz, CDCl ₃ ) δ 7.52 (m, I H) ₅ 7.46 (d, J = 8.0 Hz, 2H), 7.37 (m, 2H) _: 7.30 (m, IH), 7.10 (in, 2H), 5.70 (m Ih), 3.79 (s, 3H) ₅ 3.40 (in, 3H), 3.16 (in, IH), 3.14 (s, 3H), 2.85 (s, 3H).2.45 (m. IH), 2.10 (in, I H).

Example 27

(Z)-2-(3-(2-Cvano-3-inethylauanidino ^' )prop\lV5-(2.5-difluorophenvn-N.N-dimethyl-2-phenyl-1.3.4- thiadiaxole-3 (2H V-carboxam idc

[00248] Prepared according to the method of Example 26, using 2-(3-aminopropyl)-5-(2.5- difluorophenyl)-N,N-dimethyl-2-phenyl-l,3,4-thiadiazole-3(2H )carboxamidc (prepared as described in WO 2006-044825 Example 30) in place of 2-(3-aminopropyl)-5-(2,5-difiuorophcnyl)-N-inethoxy- N-mcthyl-2-phcnyl-l,3,4-thiadia/olc-3(2H)-carboxamide to afford the product as a mixture of cnantiomcrs. MS ESI (+) m/z 486 (M+E) detected; ¹ H NMR (400 MHz, CDCIj) δ 7.50 (in, 2H), 7.46 (m, IH), 7.38 (m, 2H), 7.29 (m, IH), 7.10 (m, 2H) _: 5.55 (m, IH), 3.37 (m, IH), 3.28 (m, IH), 3. l 8 (m, IH) ₅ 3.05 (s, 6H), 2.81 (d, J = 5.3 Hz, 3H), 2.41 (m, IH), 2.08 (in, IH), 1.67 (in, IH).

Example 28

(Z)- 1 -(3-(5-(2,5-Difluorophenyl)-3-isobutyr\ l-2-phcnyl-2,3-dilμ dro- 1.3.4-thiadiazol-2-yl)propyl)-2- inethoxyguanidine

[00249| Step A: Preparation of (3-(3-(23-difIuoropheiivD-3-isobutyryl-2-phcnyl-2.3-dihvdro-

1.3.4-thiadiazol-2-yl)propyl)cvanamide: 1 -(2-(3-aminopropyl)-5-(2,5-difluorophenyl)-2-phenyl- l,3,4-thiadiazol-3(2H)-yl)-2-mcthyipropan-I-onc (33 mg, 0.0817867 mmol) was weighed into a IO ml flask and dissolved in 1.0 niL of CH ₂ CI ₂ , followed by addition of cyanogen bromide (11.2618 ing, 0.106323 mmol) and dropwϊse addition of tricthylaminc (0.0398980 mL, 0.286253 mmol). The reaction was then stirred at ambient temperaturefor 1 hour. The reaction was then concentrated in vacuo and the resulting tan foam was used in the next step without purification. 100250) Step B: Preparation of (Z)-l-(3-(5-(2.5-difiuorophcnyl)-3-isobutyryl-2-phcnyl-2.3- dihvdro-1, 3.4-th iadia/ol-2-yl)propylV2-incthoxyatιanidiιic: Crude (3-(5-(2,5-difluorophcnyl)-3- isobutyiλ'l-2-phenyl-2,3-dihydro-l,3.4-thiadiazol-2-yl)prop yl)cλ'anamidc (35 mg, 0.08168 mmol) was transferred to a sealed tube in 3 mL of EtOH. Methoxyamine hydrochloride (170.5 mg, 2.042 mmol) and tricthylaminc (0.2846 ml, 2.042 mmol) were then added and the reaction heated to 7O ⁰ C for 18 hours. An additional 50 eq. of mclhoxyaminc hydrochloride was added along with 50 equivalents of TEA. The reaction was then heated for 24 hours. The reaction was concentrated in vacuo, and the salts washed with ethyl acetate. The filtrate was then concentrated in vacuo, and the residue was purified by flash column chromatography (5-10 % McOH/CH^Cb), to afford the desired product (14.2 mg, 36% yield) as a clear oil. MS ESI (+) m/z 476 (M+E) detected; ¹ H NMR (400 MHz, CDCb) δ 7.52 (m, IH), 7.38 (m, 4H), 7.13 (m, 3H), 3.73 (s, 3H), 3.54 (m, IH), 3.38 (m, 4H), 2.30 (m, IH), 2.13 (m, IH), 1.64 (m, I H), 1.19 (d, ./= 7.2 Hz, 6 H).

Example 29

Synthesis of: (Z)-5-(2.5-difluorophenyl)-2-(3-(2-niethoxyeuanidino)propyl) -N.N-diιnelhyl-2-phenyl-

1.3.4-thiadiay-θlc-3(2H)-carboχamidc

[00251 J Prepared according to the method of Example 28, using N,N-ditnclhyl- in place of isopropyl- substituted l,3,4-thiadiazole-3(2H)-carboxamide to afford the product as a mixture of cnantiomers. MS ESI (+) m/z 477 (M+E) detected; ¹ H NMR (400 MHz ₅ CDCb) δ 7.52 (d, J = 8.1 Hz, 2H), 7.44 (m, IH), 7.36 (m, 2H), 7.22 (m, IH), 7.09 (m, 2 H), 4.49 (m, IH), 3.67 (s, 3H), 3.21 (m, 2H), 3.16 (m. 1 H), 3.04 (s, 6H), 2.42 (m, 1 H), 2.03 (m, IH), 1.68 (m, 1 H).

(00252| The following compounds can be prepared by using the procedures described above, utilizing the appropriately substituted reagents.

Example 30

(00253] The following illustrate representative pharmaceutical dosage forms, containing a compound of Formula I ('Compound X'), for therapeutic or prophylactic use in humans.

Ct) Tablet 1 mβ/tablcl

Compound X= 100.0

Lactose 77.5

Povidone 15.0

Croscarnicllose sodium 12.0

MicrocrystalHne cellulose 92.5

Magnesium slearatc 3_0

300.0

(in Tablet 2 maλablet

Compound X= 20.0

Microcrystalline cellulose 410.0

Starch 50.0

Sodium starch glycolatc 15.0

Magnesium stearatc 10

500.0

(iii) Capsule me/capsulc

Compound X= 10.0

Colloidal silicon dioxide 1.5

Lactose 465.5

Pregelatinizcd starch 120.0

Magnesium stearatc 3J)

600.0

(iv) lnicclion 1 ( I me/ml) mg/nil

Compound X= (free acid form) i.O

Dibasic sodium phosphate 12.0

Monobasic sodium phosphate 0.7

Sodium chloride 4.5

1.0 N Sodium hydroxide solution

(pH adjustment to 7.0-7,5) q.s.

Water for injection q.s. ad 1 niL

(v) Injection 2 (10 me/ml) ma/ml

Compound X= (free acid form) 10.0

Monobasic sodium phosphate 0.3

Dibasic sodium phosphate 1.1

Polyethylene glycol 400 200.0

01 N Sodium hydroxide solution

(pH adjustment to 7.0-7.5) q.s.

Water for injection q.s. ad 1 niL

(vi") Aerosol nm/can

Compound X= 20.0

Oleic acid 10.0

Trichloromonofluoromethanc 5,000.0

Dichlorodifluoromcthanc 10,000.0

Dicliloiotctrafluoroethanc 5.000.0

J00254] The above formulations may be obtained by conventional procedures well known in the pharmaceutical art.

(00255] All publications, patents, and patent documents are incorporated by reference herein, as though individually incorporated by reference. The foregoing description is considered as illustrative only of the principles of the invention. Further, since numerous modifications and changes will be readily apparent to those skilled in the art, it is not desired to limit the invention to the exact construction and process shown as described above. Accordingly, all suitable modifications and equivalents may be considered to fall within the scope of the invention as defined by the claims that follow.

[00256] The words "comprise," "comprising," "include." "including," and "includes" when used in this specification and in the following claims arc intended to specify the presence of stated features, integers, components, or steps, but they do not preclude the presence or addition of one or more other features, integers, components, steps, or groups thereof.