TRICYCLIC INDOLE DERIVATIVES FOR USE IN THE TREATMENT OF ALZHEIMER' S DISEASE

The present invention relates to novel ketone compounds having Asp2 (β-secretase, 5 BACE1 or Memapsin-2) inhibitory activity, processes for their preparation, to compositions containing them and to their use in the treatment of diseases characterised by elevated β- amyloid levels or β-amyloid deposits, particularly Alzheimer's disease.

Alzheimer's disease is a degenerative brain disorder in which extracellular deposition of 0 Aβ in the form of senile plaques represents a key pathological hallmark of the disease (Selkoe, D. J. (2001) Physiological Reviews 81: 741-766). The presence of senile plaques is accompanied by a prominent inflammatory response and neuronal loss, β- amyloid (Aβ) exists in soluble and insoluble, fibrillar forms and a specific fibrillar form has been identified as the predominant neurotoxic species (Vassar, R. and Citron, M. (2000) 5 Neuron 27: 419-422). In addition it has been reported that dementia correlates more closely with the levels of soluble amyloid rather than plaque burden (Naslund, J. et al. (2000) J. Am. Med. Assoc. 12: 1571-1577; Younkin, S. (2001) Nat. Med. 1: 8-19). Aβ is known to be produced through the cleavage of the beta amyloid precursor protein (also known as APP) by an aspartyl protease enzyme known as Asp2 (also known as β- 0 secretase, BACE1 or Memapsin-2) (De Strooper, B. and Konig, G. (1999) Nature 402: 471-472).

Therefore, it has been proposed that inhibition of the Asp2 enzyme would reduce the level of APP processing and consequently reduce the levels of Aβ peptides found within 5 the brain. Therefore, it is also thought that inhibition of the Asp2 enzyme would be an effective therapeutic target in the treatment of Alzheimer's disease.

APP is cleaved by a variety of proteolytic enzymes (De Strooper, B. and Konig, G. (1999) Nature 402: 471-472). The key enzymes in the amyloidogenic pathway are Asp2 0 (β-secretase) and γ-secretase both of which are aspartic proteinases and cleavage of APP by these enzymes generates Aβ. The non-amyloidogenic, α-secretase pathway, which precludes Aβ formation, has been shown to be catalysed by a number of proteinases, the best candidate being ADAM10, a disintegrin and metalloproteinase. Asp1 has been claimed to show both α- and β-secretase activity in vitro. The pattern of 5 expression of Asp1 and Asp2 are quite different, Asp2 is most highly expressed in the pancreas and brain while Asp1 expression occurs in many other peripheral tissues. The Asp2 knockout mouse indicates that lack of Asp2 abolished Aβ production and also shows that in this animal model endogenous Asp1 cannot substitute for the Asp2 deficiency (Luo, Y. et al. (2001) Nat Neurosci. 4: 231-232; Cai, H. et al. (2001) Nat 0 Neurosci. 4: 233-234; Roberds, S. L. et al. (2001) Hum. MoI. Genet. 10: 1317-1324).

For an agent to be therapeutically useful in the treatment of Alzheimer's disease it is preferable that said agent is a potent inhibitor of the Asp2 enzyme, but should ideally also be selective for Asp2 over other enzymes of the aspartyl proteinase family, e.g. Cathepsin D (Connor, G. E. (1998) Cathepsin D in Handbook of Proteolytic Enzymes, Barrett, A. J., Rawlings, N. D., & Woesner, J. F. (Eds) Academic Press London. pp828- 836).

WO 2004/014843 (Takeda) and WO 2004/043916 (Merck) describe a series of ketone compounds having β-secretase activity which are implicated to be useful in the treatment of Alzheimer's disease. WO2004/094430 (Glaxo Group Ltd.; published 4 November 2004) describes a series of tricyclic indole derivatives and their use in the treatment of Alzheimer's disease.

We have found a novel series of compounds which are potent inhibitors of the Asp2 enzyme, thereby indicating the potential for these compounds to be effective in the treatment of disease characterised by elevated β-amyloid levels or β-amyloid deposits, such as Alzheimer's disease.

Thus, according to a first aspect of the present invention we provide a compound of formula (I):

(D wherein

R ¹ represents halogen or C _1-3 alkyl; R ² represents Ci _-3 alkyl, C _2-4 alkenyl, C _2-4 alkynyl, halogen, C _1-3 alkoxy, amino, cyano or hydroxy; m represents an integer from 0 to 4; n represents an integer from 0 to 2;

A-B represents -NR ⁵ -SO ₂ - ; R ⁵ represents hydrogen, C _1-6 alkyl, C _3-6 alkenyl, C _3-6 alkynyl, C _3-10 cycloalkyl, -C _0-6 alkyl- aryl, -C _0-6 alkyl-heteroaryl, -C _0-6 alkyl-heterocyclyl, -C _3-10 cycloalkyl-aryl, -C _3-10 cycloalkyl- heteroaryl or -C _3-10 cycloalkyl-heterocyclyl;

-W- represents -CH ₂ -, -(CHz) ₂ -, -(CHz) ₃ - Or -C(H)=C(H)-CH ₂ -;

X-Y-Z represents -N-CR ⁸ =CR ⁹ -; R ⁸ represents hydrogen, Ci _-6 alkyl or C _3-10 cycloalkyl;

R ⁹ represents hydrogen, Ci _-6 alkyl, Ci _-6 alkoxy, C _3- Io cycloalkyl, -C _0-6 alkyl-aryl, -C _0-6 alkyl- heteroaryl, -C _0-6 alkyl-heterocyclyl, -C _3-10 cycloalkyl-aryl, -C _3-10 cycloalkyl-heteroaryl or - C _3-I0 cycloalkyl-heterocyclyl;

R ³ represents Ci _-6 alkyl, C _2-6 alkenyl, C _2-6 alkynyl, -Ci _-6 alkyl-C _3-10 cycloalkyl, -C _0-6 alkyl- aryl, -C ₀ . ₆ alkyl-heteroaryl or -C _0-6 alkyl-heterocyclyl;

R ⁴ represents hydrogen, C ₁ - _I0 alkyl, C _3-10 alkenyl, C _3-10 alkynyl, -C _3-10 cycloalkyl, -C _3- - _I0 cycloalkenyl, -C _0-6 alkyl-aryl, -C _0-6 alkyl-heteroaryl, -C ₀ . ₆ alkyl-heterocyclyl, -C _1-6 alkyl-C ₃ , i ₀ cycloalkyl, -C _3-10 cycloalkyl-aryl, -C _3- i ₀ cycloalkyl-heteroaryl, -C _3-10 cycloalkyl- heterocyclyl, -C(R ^a R ^b )-CONH-Ci _-6 alkyl, -C(R ^a R ^b )-CONH-C _3-10 cycloalkyl, -C _2-6 alkyl-S-d. ₆ alkyl, -C _2-6 alkyl-NR ^c R ^d , -C(R ^a R ^b )-C _1-6 alkyl, -C(R ^a R ^b )-C _0-6 alkyl-aryl, -C(R ^a R ^b )-C _0-6 alkyl- heteroaryl, -C(R ^a R ^b )-C _o-6 alkyl-heterocyclyl, -C _2-6 alkyl-0-C _o-6 alkyl-aryl, -C _2-6 alkyl-0-C _o-6 alkyl-heteroaryl Or -C _2-6 alkyl-0-C _o-6 alkyl-heterocyclyl;

R ^a and R ^b independently represent hydrogen, Ci _-6 alkyl or R ^a and R ^b together with the carbon atom to which they are attached may form a C _3-10 cycloalkyl or heterocyclyl group;

R ^c and R ^d independently represent hydrogen, Ci _-6 alkyl, C _3-I0 cycloalkyl or R ^c and R ^d together with the nitrogen atom to which they are attached may form a nitrogen containing heterocyclyl group; wherein said alkyl and cycloalkyl groups may be optionally substituted by one or more (e.g. 1 to 6) halogen, C _1-6 alkyl, haloC _1-6 alkyl, C _1-6 alkoxy, haloCi _-6 alkoxy, C _1-6 alkylamino, amino, cyano, hydroxy or -COOR ²² groups; and wherein said aryl, heteroaryl or heterocyclyl groups may be optionally substituted by one or more (e.g. 1 to 5) C _1-6 alkyl, halogen, haloC _1-6 alkyl, haloC _1-6 alkoxy, oxo, hydroxy, C _1-6 alkoxy, C _2-6 alkynyl, C _2-6 alkenyl, amino, cyano, nitro, -NR ²² COR ²³ , -CONR ²² R ²³ - SO ₂ R ²² , -SO ₂ NR ²² R ²³ , -COOR ²² , -C _1-6 alkyl-NR ²² R ²³ , -C _1-6 alkyl-O-C _1-6 alkyl or -C _1-6 alkanoyl groups (wherein R ²² and R ²³ independently represent hydrogen, C _1-6 alkyl or C _3-

₈ cycloalkyl); or a pharmaceutically acceptable salt or solvate thereof.

When W represents -C(H)=C(H)-CH ₂ -, the terminal sp2 hybridised carbon is attached to B.

In one aspect, the invention provides compounds of formula (I) wherein: R ¹ represents halogen or Ci _-3 alkyl; R ² represents C _1-3 alkyl, C _2-4 alkenyl, C _2-4 alkynyl, halogen, C _1-3 alkoxy, amino, cyano or hydroxy; m represents an integer from 0 to 4; n represents an integer from 0 to 2; A-B represents -NR ⁵ -SO ₂ - or -NR ⁵ -CO-; R ⁵ represents hydrogen, C _1-6 alkyl, C _3-6 alkenyl, C _3-6 alkynyl, C _3-10 cycloalkyl, -C _0-6 alkyl- aryl, -Co- ₆ alkyl-heteroaryl, -C _0-6 alkyl-heterocyclyl, -C _3-10 cycloalkyl-aryl, -C _3-10 cycloalkyl- heteroaryl or -C _3- - _I0 cycloalkyl-heterocyclyl;

-W- represents -CH ₂ -, -(CH ₂ ) ₂ -, -(CH ₂ )S-, -C(H)=C(H)- Or -CH ₂ -C(H)=C(H)-; X-Y-Z represents -N-CR ^δ =CR ⁹ -; R ⁸ represents hydrogen, C _1-6 alkyl or C _3-10 CyClOaIRyI;

R ⁹ represents hydrogen, Ci _-6 alkyl, C _1-6 alkoxy, C _3-I0 cycloalkyl, -C _0-6 alkyl-aryl, -C _0-6 alkyl- heteroaryl, -C ₀ .e alkyl-heterocyclyl, -C _3-10 cycloalkyl-aryl, -C _3- i ₀ cycloalkyl-heteroaryl or - C _3-10 cycloalkyl-heterocyclyl;

R ³ represents Ci _-6 alkyl, C _2-6 alkenyl, C _2-6 alkynyl, -Ci _-6 alkyl-C _3-1o cycloalkyl, -C _0-6 alkyl- aryl, -C _0-6 alkyl-heteroaryl or -C _0-6 alkyl-heterocyclyl; R ⁴ represents hydrogen, C ₁ - _I0 alkyl, C _2-10 alkenyl, C _2-10 alkynyl, -C _3-I0 cycloalkenyl, -C _0-6 alkyl-aryl, -C _0-6 alkyl-heteroaryl, -C _0-6 alkyl-heterocyclyl, -C _0-6 alkyl-C ₃ . ₁₀ cycloalkyl, -C _3-10 cycloalkyl-aryl, -C _3-10 cycloalkyl-heteroaryl, -C _3-I0 cycloalkyl-heterocyclyl, -C(R ^a R ^b )- CONH-C _1-6 alkyl, -C(R ^a R ^b )-CONH-C _3-10 cycloalkyl, -C _2-6 alkyl-S-C _1-6 alkyl, -C _2-6 alkyl- NR ^c R ^d , -C(R ^a R ^b )-C _o-6 alkyl-aryl, -C(R ^a R ^b )-C _0-6 alkyl-heteroaryl, -C(R ^a R ^b )-C _0-6 alkyl- heterocyclyl, -C _2-6 alkyl-O-C ₀ . ₆ alkyl-aryl, -C _2-6 alkyl-0-C _o-6 alkyl-heteroaryl or -C _2-6 alkyl- 0-C _0-6 alkyl-heterocyclyl;

R ^a and R ^b independently represent hydrogen, Ci _-6 alkyl or R ^a and R ^b together with the carbon atom to which they are attached may form a C _3-10 cycloalkyl or heterocyclyl group;

R ^c and R ^d independently represent hydrogen, C _1-6 alkyl, C ₃ - _I0 cycloalkyl or R ^c and R ^d together with the nitrogen atom to which they are attached may form a nitrogen containing heterocyclyl group; wherein said alkyl and cycloalkyl groups may be optionally substituted by one or more (e.g. 1 to 6) halogen, Ci _-6 alkyl, haloCi _-6 alkyl, Ci _-6 alkoxy, haloC _1-6 alkoxy, C _1-6 alkylamino, amino, cyano, hydroxy or -COOR ²² groups; and wherein said aryl, heteroaryl or heterocyclyl groups may be optionally substituted by one or more (e.g. 1 to 5) C _1-6 alkyl, halogen, haloC _1-6 alkyl, haloC _1-6 alkoxy, oxo, hydroxy, C _1-6 alkoxy, C _2-6 alkynyl, C _2-6 alkenyl, amino, cyano, nitro, -NR ²² COR ²³ , -CONR ²² R ²³ - SO ₂ R ²² , -SO ₂ NR ²² R ²³ , -COOR ²² , -C _1-6 alkyl-NR ²² R ²³ , -C _1-6 alkyl-O-C _1-6 alkyl or -C _1-6 alkanoyl groups (wherein R ²² and R ²³ independently represent hydrogen, Ci _-6 alkyl or C ₃ , ₈ cycloalkyl); or a pharmaceutically acceptable salt or solvate thereof.

In a more particular aspect, -W- represents -CH ₂ -, -(CH ₂ ) ₂ - or -(CH ₂ ) ₃ -, particularly CH ₂

In another aspect, R ⁴ represents hydrogen, Ci _-10 alkyl, C _3-10 alkenyl, C _3-10 alkynyl, -C _3-10 cycloalkenyl, -C _0-6 alkyl-aryl, -C _0-6 alkyl-heteroaryl, -C _0-6 alkyl-heterocyclyl, -C _0-6 alkyl-C _{3- K} ) cycloalkyl, -C _3- i ₀ cycloalkyl-aryl, -C _3- i ₀ cycloalkyl-heteroaryl, -C ₃ - _I0 cycloalkyl- heterocyclyl, -C(R ^a R ^b )-CONH-Ci _-6 alkyl, -C(R ^a R ^b )-CONH-C _3- i ₀ cycloalkyl, -C _2-6 alkyl-S-d. ₆ alkyl, -C _2-6 alkyl-NR°R ^d , -C(R ^a R ^b )-C _0-6 alkyl-aryl, -C(R ^a R ^b )-C _o-6 alkyl-heteroaryl, - C(R ^a R ^b )-C ₀ -6 alkyl-heterocyclyl, -C _2-6 alkyl-0-C _o-6 alkyl-aryl, -C _2-6 alkyl-0-C _o . ₆ alkyl- heteroaryl or -C _2-6 alkyl-O-Co-e alkyl-heterocyclyl.

In yet another aspect, A-B represents -NR ⁵ -SO ₂ .

The term 'C _x-y alkyl' as used herein as a group or a part of the group refers to a linear or branched saturated hydrocarbon group containing from x to y carbon atoms. Examples of C _1-6 alkyl groups include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert butyl, n-pentyl, isopentyl, neopentyl or hexyl and the like.

The term 'C _x-y alkenyl' as used herein refers to a linear or branched hydrocarbon group containing one or more carbon-carbon double bonds and having from x to y carbon atoms. Examples of C _2-6 alkenyl groups include ethenyl, propenyl, butenyl, pentenyl or hexenyl and the like.

The term 'C _x-y alkynyl' as used herein refers to a linear or branched hydrocarbon group containing one or more carbon-carbon triple bonds and having from x to y carbon atoms. Examples of C _2-6 alkynyl groups include ethynyl, propynyl, butynyl, pentynyl or hexynyl and the like.

The term 'C _x-y alkoxy' as used herein refers to an -O-C _x-y alkyl group wherein C _x-y alkyl is as defined herein. Examples of C _1-6 alkoxy groups include methoxy, ethoxy, propoxy, butoxy, pentoxy or hexoxy and the like.

The term 'C _x-y cycloalkyl' as used herein refers to a saturated monocyclic hydrocarbon ring of x to y carbon atoms. Examples of C _3-10 cycloalkyl groups include cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl or cyclooctyl and the like.

The term 'C _x-y cycloalkenyl' as used herein refers to an unsaturated non-aromatic monocyclic hydrocarbon ring of x to y carbon atoms containing one or more carbon- carbon double bonds. Examples of C _3- - _I0 cycloalkenyl groups include cyclopropenyl, cyclobutenyl, cyclopentenyl, cyclohexenyl, cycloheptenyl or cyclooctenyl and the like.

The term 'halogen' as used herein refers to a fluorine, chlorine, bromine or iodine atom.

The term 'haloC _x . _y alkyl' as used herein refers to a C _x-y alkyl group as defined herein wherein at least one hydrogen atom is replaced with halogen. Examples of haloCi _-6 alkyl groups include fluoroethyl, trifluoromethyl or trifluoroethyl and the like.

The term 'halo C _x-y alkoxy' as used herein refers to a C _x-y alkoxy group as herein defined wherein at least one hydrogen atom is replaced with halogen. Examples of halo C _1-6 alkoxy groups include difluoromethoxy or trifluoromethoxy and the like.

The term 'aryl' as used herein refers to a C _6- i2 monocyclic or tricyclic hydrocarbon ring wherein at least one ring is aromatic. Examples of such groups include phenyl, naphthyl or tetrahydronaphthalenyl and the like.

The term 'heteroaryl' as used herein refers to a 5-6 membered monocyclic aromatic or a fused 8-10 membered bicyclic aromatic ring, which monocyclic or bicyclic ring contains 1 to 4 heteroatoms selected from oxygen, nitrogen and sulphur. Examples of such monocyclic aromatic rings include thienyl, furyl, furazanyl, pyrrolyl, triazolyl, tetrazolyl, imidazolyl, oxazolyl, thiazolyl, oxadiazolyl, isothiazolyl, isoxazolyl, thiadiazolyl, pyranyl, pyrazolyl, pyrimidyl, pyridazinyl, pyrazinyl, pyridyl, triazinyl, tetrazinyl and the like. Examples of such fused aromatic rings include quinolinyl, isoquinolinyl, quinazolinyl, quinoxalinyl, pteridinyl, cinnolinyl, phthalazinyl, naphthyridinyl, indolyl, isoindolyl, azaindolyl, indolizinyl, indazolyl, purinyl, pyrrolopyridinyl, furopyridinyl, benzofuranyl, isobenzofuranyl, benzothienyl, benzoimidazolyl, benzoxazolyl, benzoisoxazolyl, benzothiazolyl, benzoisothiazolyl, benzoxadiazolyl, benzothiadiazolyl and the like.

The term 'heterocyclyl' refers to a 4-7 membered monocyclic ring or a fused 8-12 membered bicyclic ring which may be saturated or partially unsaturated, which monocyclic or bicyclic ring contains 1 to 4 heteroatoms selected from oxygen, nitrogen or sulphur. Examples of such monocyclic rings include pyrrolidinyl, azetidinyl, pyrazolidinyl, oxazolidinyl, piperidinyl, piperazinyl, morpholinyl, thiomorpholinyl, thiazolidinyl, hydantoinyl, valerolactamyl, oxiranyl, oxetanyl, dioxolanyl, dioxanyl, oxathiolanyl, oxathianyl, dithianyl, dihydrofuranyl, tetrahydrofuranyl, dihydropyranyl, tetrahydropyranyl, tetrahydropyridinyl, tetrahydropyrimidinyl, tetrahydrothiophenyl, tetrahydrothiopyranyl, diazepanyl, azepanyl and the like. Examples of such bicyclic rings include indolinyl, isoindolinyl, benzopyranyl, quinuclidinyl, 2,3,4,5-tetrahydro-1H-3-benzazepine, tetrahydroisoquinolinyl and the like.

The term 'nitrogen containing heterocyclyl' is intended to represent any heterocyclyl group as defined above which contains a nitrogen atom.

In one embodiment, R ⁵ represents hydrogen, C _1-6 alkyl (e.g. methyl, ethyl or i-propyl) optionally substituted by one or more (e.g. 1 , 2 or 3) halogen atoms (e.g. trifluoroethyl) or -Co- ₆ alkyl-aryl (e.g. phenyl or benzyl).

In a more particular embodiment, R ⁵ represents C _1-6 alkyl (e.g. methyl or ethyl) optionally substituted by one or more (e.g. 1 , 2 or 3) halogen atoms (e.g. trifluoroethyl), particularly methyl.

In another embodiment, -W- represents CH ₂ or ~(CH ₂ ) ₂ -. More particularly, W represents -(CH ₂ J ₂ -.

In yet another embodiment, m represents 0-2, more particularly, 0 or 1 and most particularly 0.

In certain embodiments in which m is not 0, R ¹ is C _1-3 alkyl (e.g. methyl).

In another embodiment, n represents 0.

In a further, R ⁸ represents hydrogen.

In one embodiment, R ⁹ represents hydrogen or C _1-6 alkyl (e.g. methyl, ethyl, propyl or isopropyl). In a more particular embodiment, R ⁹ represents C _1-6 alkyl (e.g. ethyl, propyl or isopropyl). Most particularly, R ⁹ represents ethyl.

In another embodiment, R ³ represents -C _0-6 alkyl-aryl (e.g. benzyl) optionally substituted by one or two halogen atoms (e.g. chlorine or fluorine). For example, R ³ may represent unsubstituted benzyl, 3-chlorobenzyl, 3-fluorobenzyl or 3,5-difluorobenzyl. In a more particular embodiment, R ³ represents unsubstituted benzyl.

In one embodiment, R ⁴ represents hydrogen, C _1- - _I0 alkyl, C _3-10 alkenyl, C _3-10 alkynyl, -C _0-6 alkyl-C _3-8 cycloalkyl (i.e. -C _3-10 cycloalkyl and -C _1-6 alkyl-C _3-8 cycloalkyl), -C _0-6 alkyl-aryl, - C _0-6 alkyl-heteroaryl, -C _0-6 alkyl-heterocyclyl, -C(R ^a R ^b )-CO N H-C _3-10 cycloalkyl or -C _3-10 cycloalkyl-aryl.

In a more particular embodiment, the aryl, heteroaryl and heterocyclyl groups of R ⁴ may optionally be substituted by one or more (e.g. 1 , 2 or 3) substituents selected from the group consisting of halogen, C _1-6 alkyl, C _1-6 alkoxy, haloC _1-6 alkyl, haloC _1-6 alkoxy and - CONR ²² R ²³ , wherein R ²² and R ²³ independently represent hydrogen or Ci _-6 alkyl.

In certain embodiments in which the aryl, heteroaryl or heterocyclyl groups of R ⁴ are 6 membered rings that are substituted by one substituent, the substituent is in the 3- position relative to the attachment position.

In a more particular embodiment, the alkyl, and cycloalkyl groups of R ⁴ may optionally be substituted by one or more (e.g. 1 to 6) substituents selected from the group consisting of halogen, C _1-6 alkyl, haloCi _-6 alkyl, C _1-6 alkoxy and haloC _1-6 alkoxy. More particularly, the substiutents are selected from the group consisting of halogen and C _1-6 alkoxy.

In a more particular embodiment, R ⁴ represents hydrogen;

C- _I-I0 alkyl (e.g. methyl, ethyl, i-propyl, propyl, methylpropyl, dimethylethyl, butyl, 1 ,5-dimethylhexyl or 1 ,1 ,5-trimethylhexyl) optionally substituted by one or more halogen

(e.g. fluoroethyl, difluoroethyl, trifluoroethyl or pentafluoropropyl) or Ci _-6 alkoxy (e.g. methoxy) groups;

C _3-I Q alkenyl (e.g. ethenyl);

C _3- io alkynyl (e.g. propynyl);

-C _0-6 alkyl-C _3-8 cycloalkyl (e.g. -CHs-cyclopropyl, cyclopropyl, cyclobutyl, cyclopentyl or cyclohexyl) optionally substituted by one or more halogen atoms (e.g. fluorine) or Ci _-6 alkyl groups (e.g. methyl);

-C _0-6 alkyl-aryl (e.g. phenyl, dihydroindenyl, benzyl, 1 -methyl- 1-phenylethyl, ethylphenyl or α,α-dimethylbenzyl) optionally substituted (e.g. substituted at the 3 and 5 positions) by one or more halogen, cyano, nitro, haloCi _-6 alkyl (e.g. -CF ₃ ), haloCi _-6 alkoxy (e.g. -OCF ₃ ), C _1-6 alkyl (e.g. methyl), C _1-6 alkoxy (e.g. methoxy), C _2-6 alkynyl, C _2-6 alkenyl, amino, -NR ²² COR ²³ , -CONR ²² R ²³ -SO ₂ R ²² , -SO ₂ NR ²² R ²³ , -COOR ²² , -C _1-6 alkyl-NR ²² R ²³ , -C _1-6 alkanoyl or hydroxy groups;

-C _0-6 alkyl-heteroaryl (e.g. -pyridinyl, -CH ₂ -pyrazolyl, -CH ₂ -pyridinyl, -CH ₂ - quinoxalinyl, -CH ₂ -quinolinyl, -CH ₂ -thienyl, -CH ₂ -pyrazinyl or -CH ₂ -isoxazolyl) optionally substituted by one or more C _1-6 alkyl (e.g. methyl or ethyl), halogen (e.g. bromine), haloC _1-6 alkyl (e.g. trifluoroethyl) or -CONR ²² R ²³ (e.g. -CONHMe) groups;

-C _0-6 alkyl-heterocyclyl (e.g. tetrahydropyranyl) optionally substituted by one or more C _1-6 alkyl (e.g. methyl) groups;

-C(R ^a R ^b )-CONH-C _3-10 cycloalkyl (e.g. C(R ^a R ^b )-CONH-cyclohexyl); or

-C _3-10 cycloalkyl-aryl.

In one aspect, R ^a and R ^b independently represent hydrogen or methyl, or R ^a and R ^b together with the carbon atom to which they are attached form a cyclopropyl or cyclohexyl group. More particularly R ^a and R ^b both represent hydrogen, both represent methyl or together with the carbon atom to which they are attached form a cyclopropyl group.

In an even more particular embodiment, R ⁴ represents hydrogen;

C _1-10 alkyl (e.g. methyl, ethyl, i-propyl, propyl, methylpropyl, dimethylethyl, butyl, or 1 ,1 ,5-trimethylhexyl) optionally substituted by one or more halogen (e.g. fluoroethyl, difluoroethyl, trifluoroethyl or pentafluoropropyl) or Ci _-6 alkoxy (e.g. methoxy) groups;

C _3-10 alkynyl (e.g. propynyl);

-C _0-6 alkyl-C _3-8 cycloalkyl (e.g. -CH ₂ -cyclopropyl, cyclopropyl, cyclobutyl, cyclopentyl or cyclohexyl) optionally substituted by one or more halogen atoms (e.g. fluorine);

-C _0-6 alkyl-aryl (e.g. dihydroindenyl, benzyl, ethylphenyl or α,α-dimethylbenzyl) optionally substituted (e.g. substituted at the 3 position) by one or more haloCi _-6 alkyl (e.g. -CF ₃ ), haloC _1-6 alkoxy (e.g. -OCF ₃ ), Ci _-6 alkyl (e.g. methyl) or C _1-6 alkoxy (e.g. methoxy) groups; -C _0-6 alkyl-heteroaryl (e.g. -pyridinyl, -CH ₂ -pyrazolyl, -CH ₂ -pyridinyl, -CH ₂ - quinoxalinyl, -CH ₂ -quinolinyl, -CH ₂ -thienyl, -CH ₂ -pyrazinyl or -CH ₂ -isoxazolyl) optionally

substituted by one or more C _1-6 alkyl (e.g. methyl or ethyl), halogen (e.g. bromine) or haloC _1-6 alkyl (e.g. trifluoroethyl) groups; or

-C _0-6 alkyl-heterocyclyl (e.g. tetrahydropyranyl) optionally substituted by one or more Ci _-6 alkyl (e.g. methyl) groups.

Most particularly, R ⁴ represents

-Co- ₆ alkyl-heterocyclyl (e.g. tetrahydropyran-4-yl); or

-Co- ₆ alkyl-aryl (e.g. benzyl) optionally substituted by one or more Ci _-6 alkoxy (e.g. methoxy) groups.

In one aspect, the invention provides compounds of formula (I) and pharmaceutically acceptable salts and solvates thereof, wherein:

R ¹ represents Ci _-3 alkyl; m represents an integer from 0 to 2; n represents 0;

A-B represents -NR ⁵ -SO ₂ -;

R ⁵ represents hydrogen or Ci _-6 alkyl optionally substituted by one or more (e.g. 1 , 2 or 3) halogen atoms; -W- represents -CH ₂ - or -(CH ₂ )Z-;

X-Y-Z represents -N-CR ⁸ =CR ⁹ -;

R ⁸ represents hydrogen;

R ⁹ represents Ci _-6 alkyl;

R ³ represents -C _0-6 alkyl-aryl optionally substituted by one or two halogen atoms; R ⁴ represents hydrogen, Ci _-10 alkyl, C _3- - _I0 alkenyl, C _3-I0 alkynyl, -C _0-6 alkyl-C _3-8 cycloalkyl, -

C _0-6 alkyl-aryl, -C _0-6 alkyl-heteroaryl, -C ₀ . ₆ alkyl-heterocyclyl, -C(R ^a R ^b )-CONH-C _3- io cycloalkyl or -C ₃ _i ₀ cycloalkyl-aryl;

R ^a and R ^b independently represent hydrogen or methyl, or R ^a and R ^b together with the carbon atom to which they are attached may form a cyclopropyl or cyclohexyl group; wherein said alkyl and cycloalkyl groups of R ⁴ may be optionally substituted by one or more (e.g. 1 to 6) halogen, Ci _-6 alkyl, haloC^alkyl, d _-6 alkoxy and haloCi _-6 alkoxy groups; and wherein said aryl, heteroaryl or heterocyclyl groups of R ⁴ may be optionally substituted by one or more (e.g. 1 , 2 or 3) halogen, Ci _-6 alkyl, Ci _-6 alkoxy, haloCi_ ₆ alkyl, haloCi _-6 alkoxy and -CONR ²² R ²³ groups (wherein R ²² and R ²³ independently represent hydrogen or Ci _-6 alkyl).

In a more particular aspect, the invention provides compounds of formula (I) and pharmaceutically acceptable salts and solvates thereof, wherein: m and n represent 0; A-B represents -NR ⁵ -SO ₂ -;

R ⁵ represents hydrogen or Ci _-6 alkyl optionally substituted by one or more (e.g. 1 , 2 or 3) halogen atoms;

-W- represents -(CH ₂ ) ₂ -; X-Y-Z represents -N-CR ⁸ =CR ⁹ -; R ⁸ represents hydrogen; R ⁹ represents C _1-6 alkyl; R ³ represents benzyl;

R ⁴ represents hydrogen, C _1-10 alkyl, C _3-I0 alkynyl, -C _0-6 alkyl-C _3-8 cycloalkyl, -C _0-6 alkyl- aryl, -C _0-6 alkyl-heteroaryl or -C _0-6 alkyl-heterocyclyl; wherein said alkyl and cycloalkyl groups of R ⁴ may be optionally substituted by one or more (e.g. 1 to 6) halogen and C-ι _-6 alkoxy groups; and wherein said aryl, heteroaryl or heterocyclyl groups of R ⁴ may be optionally substituted by one or more (e.g. 1 , 2 or 3) halogen, Ci. ₆ alkyl, C _1-6 alkoxy, haloC _1-6 alkyl, haloC _1-6 alkoxy and -CONR ²² R ²³ groups (wherein R ²² and R ²³ independently represent hydrogen or C _1-6 alkyl).

Compounds according to the invention include examples E1-2 as shown below, or a pharmaceutically acceptable salt or solvate thereof.

The compounds of formula (I) can form acid addition salts thereof. It will be appreciated that for use in medicine the salts of the compounds of formula (I) should be pharmaceutically acceptable. Suitable pharmaceutically acceptable salts will be apparent to those skilled in the art and include those described in J. Pharm. ScL, 1977, 66, 1-19, such as acid addition salts formed with inorganic or organic acids e.g. hydrochlorides, hydrobromides, sulphates, phosphates, acetates, benzoates, citrates, nitrates, succinates, lactates, tartrates, fumarates, maleates, 1-hydroxy-2-naphthoates, palmoates, methanesulphonates, p-toluenesulphonates, naphthalenesulphonates, formates or trifluoroacetates. The present invention includes within its scope all possible stoichiometric and non-stoichiometric forms.

A pharmaceutically acceptable acid addition salt can be formed by reaction of a compound of formula (I) with a suitable inorganic or organic acid (such as hydrobromic, hydrochloric, sulfuric, nitric, phosphoric, succinic, maleic, formic, acetic, propionic, fumaric, citric, tartaric, lactic, benzoic, salicylic, glutamaic, aspartic, p-toluenesulfonic, benzenesulfonic, methanesulfonic, ethanesulfonic, naphthalenesulfonic such as 2- naphthalenesulfonic, or hexanoic acid), optionally in a suitable solvent such as an organic solvent, to give the salt which is usually isolated for example by crystallisation and filtration.

The compounds of formula (I) may be prepared in crystalline or non-crystalline form, and, if crystalline, may optionally be solvated, e.g. as the hydrate. The invention includes within its scope all possible stoichiometric and non-stoichiometric forms of the

salts of the compounds of formula (I) including hydrates and solvates as well as compounds containing variable amounts of solvent (e.g water). Certain compounds of formula (I) are capable of existing in stereoisomeric forms (e.g. diastereomers and enantiomers) and the invention extends to each of these stereoisomeric forms and to mixtures thereof including racemates. The different stereoisomeric forms may be separated one from the other by the usual methods, or any given isomer may be obtained by stereospecific or asymmetric synthesis. The invention also extends to any tautomeric forms and mixtures thereof. Preferably, compounds of formula (I) are in the form of a single enantiomer of formula (Ia):

(Ia)

The compounds of formula (I) and salts and solvates thereof may be prepared by the methodology described hereinafter, constituting a further aspect of this invention.

A process according to the invention for preparing a compound of formula (I) which comprises:

(a) oxidation of a compound of formula (II)

(H) wherein R ¹ , R ² , R ³ , R ⁴ , m, n, A, B ₁ W, X, Y and Z are as defined above and P ¹ represents a suitable protecting group such as -COOC(CH ₃ ) ₃ followed by deprotection to remove the P ¹ protecting group;

(b) deprotecting a compound of formula (I) which is protected; or

(c) interconversion from one compound of formula (I) to another.

Process (a) typically comprises the use of an oxidising reagent such as Dess-Martin periodinane in an appropriate solvent such as dichloromethane at an appropriate range of temperature such as O ⁰ C to room temperature.

In processes (a) and (b), examples of protecting groups and the means for their removal can be found in T. W. Greene and P. G. M. Wuts 'Protective Groups in Organic Synthesis' (J. Wiley and Sons, 3rd Ed. 1999). Suitable amine protecting groups include aryl sulphonyl (e.g. tosyl), acyl (e.g. acetyl), carbamoyl (e.g. benzyloxycarbonyl or t- butoxycarbonyl) and arylalkyl (e.g. benzyl), which may be removed by hydrolysis or hydrogenolysis as appropriate. Other suitable amine protecting groups include trifluoroacetyl (-COCF ₃ ) which may be removed by base catalysed hydrolysis. Suitable hydroxy protecting groups would be silyl based groups such as t-butyldimethylsilyl, which may be removed using standard methods, for example use of an acid such as trifluoroacetic or hydrochloric acid or a fluoride source such as tetra n-butylammonium fluoride.

Process (c) may be performed using conventional interconversion procedures such as epimerisation, oxidation, reduction, alkylation, aromatic substitution, ester hydrolysis, amide bond formation or removal and sulphonylation. For example, compounds of formula (I) wherein W represents -CH ₂ -C(H)=C(H)- may be converted to compounds of formula (I) wherein W represents -(CH ₂ ) ₂ - or -(CH ₂ ) ₃ - by catalytic hydrogenation compounds as herein described.

Compounds of formula (II) wherein W is -CH ₂ - or -(CH ₂ ) ₂ - may be prepared using the process described in WO2004/094430 (PCT/EP2004/004244).

In the specific case where W is -CH ₂ -C(H)=C(H)- and wherein R ⁵ represents hydrogen, the compound of formula (II) may be prepared according to the following process:

wherein R ¹ , R ² , R ³ , R ⁴ , R ⁹ m, n, A, B, X, Y, Z and P ¹ are as defined above, P ² represents a suitable group such as Ci _-6 alkyl, P ³ represents a suitable protecting group such as trimethylsilyl, L ¹ , L ² and L ³ independently represent a suitable leaving group such as a halogen atom (e.g. chlorine or iodine) and p and q represent an integer such that p+q represents m.

Step (i) typically comprises treatment with Pd(OAc) ₂ and LiCI in the presence of a suitable base (e.g. potassium carbonate) in a suitable solvent such as dimethylformamide at a suitable temperature such as 100 ⁰ C.

Step (ii) is a deprotection step and may be carried out as described above for processes (a) and (b). When P ³ represents a trimethylsilyl, this may be removed by treatment with a fluoride source such as tetra n-butylammonium fluoride (TBAF), in a suitable solvent such as tetrahydrofuran at a suitable temperature such as room temperature.

Step (iii) typically comprises the use of a suitable base such as sodium hydride in the presence of a suitable solvent such as DMF at a suitable temperature, such as room temperature.

Step (iv) typically comprises the use of a suitable reducing agent such as Fe(O) in a suitable solvent such as acetic acid at a suitable temperature, such as room temperature.

Step (v) typically comprises the use of a suitable base such as pyridine/DMAP in the presence of a suitable solvent such as dichloromethane at a suitable temperature, such as room temperature.

Step (vi) typically comprises the use of a suitable catalyst such as tricyclohexylphosphine [1 ,3-bis(2,4,6-trimethyl-phenyl)-4,5-dihydro-imidazol-2- ylidene][benzylidine]ruthenium (IV) dichloride in the presence of a suitable solvent such as toluene at a suitable temperature such as reflux

Step (vii) typically comprises a standard procedure for conversion of a carboxylic ester to an acid, such as the use of an appropriate alkali metal hydroxide like lithium or sodium hydroxide in an appropriate solvent such as methanol at an appropriate temperature such as room temperature. In the case of a tert-butyl ester this conversion can be achieved by the use of an appropriate acid such as trifluoroacetic acid in an appropriate solvent such as dichloromethane at an appropriate temperature such as 0 ⁰ C.

Step (viii) typically comprises reacting a compound of formula (IX) with a compound of formula (X) in the presence of water soluble carbodiimide and HOBT and a suitable base

such as a tertiary alkylamine (e.g. 4 ethyl morpholine) or pyridine in a suitable solvent such as DMF and at a suitable temperature, e.g. between 0 ⁰ C and room temperature.

Compounds of formula (II) wherein W represents -(CH ₂ ) ₃ - may be prepared in an identical manner to the process described above except an additional step is required in which compounds of formula (X) are reduced prior to step (vii). This step, typically comprises the use of reducing agents such as sodium borohydride in a suitable solvent such as methanol at a suitable temperature such as room temperature.

Compounds of formula (IX) or formula (X) in which R ⁵ is hydrogen can be converted into compounds of formula (IX) or formula (X) in which R ⁵ has an alternative definition (e.g. C _1-6 alkyl) by treatment with an alkylating agent, such as an alkyl iodide (e.g. methyl iodide) in the presence of a suitable base such as potassium carbonate in a suitable solvent such as dimethyl formamide at a suitable temperature such as room temperature.

Compounds of formula (X) may be prepared by protecting a compound of formula (III) from WO2004/094430.

As a further aspect of the invention there is thus provided a compound of formula (I) or a pharmaceutically acceptable salt or solvate thereof for use as a pharmaceutical, particularly in the treatment of patients with diseases characterised by elevated β- amyloid levels or β-amyloid deposits.

According to another aspect of the invention, there is provided the use of a compound of formula (I) or a physiologically acceptable salt or solvate thereof for the manufacture of a medicament for the treatment of patients with diseases characterised by elevated β- amyloid levels or β-amyloid deposits.

In a further or alternative aspect there is provided a method for the treatment of a human or animal subject with diseases characterised by elevated β-amyloid levels or β-amyloid deposits, which method comprises administering to said human or animal subject an effective amount of a compound of formula (I) or a physiologically acceptable salt or solvate thereof.

As a further aspect of the invention there is thus provided a pharmaceutical composition comprising a compound of formula (I) or a pharmaceutically acceptable salt or solvate thereof for use in the treatment of diseases characterised by elevated β-amyloid levels or β-amyloid deposits.

It will be appreciated by those skilled in the art that reference herein to treatment extends to prophylaxis as well as the treatment of diseases characterised by elevated β-amyloid levels or β-amyloid deposits.

The compounds according to the invention may be formulated for administration in any convenient way, and the invention therefore also includes within its scope pharmaceutical compositions for use in the therapy of diseases characterised by elevated β-amyloid levels or β-amyloid deposits, comprising a compound of formula (I) or a physiologically acceptable salt or solvate thereof together, if desirable, with one or more physiologically acceptable diluents or carriers.

It will be appreciated that diseases characterised by elevated β-amyloid levels or β- amyloid deposits include Alzheimer's disease, mild cognitive impairment, Down's syndrome, hereditary cerebral haemorrhage with β-amyloidosis of the Dutch type, cerebral β-amyloid angiopathy and various types of degenerative dementias, such as those associated with Parkinson's disease, progressive supranuclear palsy, cortical basal degeneration and diffuse Lewis body type of Alzheimer's disease.

Most preferably, the disease characterised by elevated β-amyloid levels or β-amyloid deposits is Alzheimer's disease.

There is also provided a process for preparing such a pharmaceutical formulation which comprises mixing the ingredients.

Compounds of formula (I) may be used in combination with other therapeutic agents. Suitable examples of such other therapeutic agents may be acetylcholine esterase inhibitors (such as tetrahydroaminoacridine, donepezil hydrochloride and rivastigmine), gamma secretase inhibitors, histamine H3 antagonists, 5HT4 partial agonists, anti¬ inflammatory agents (such as cyclooxygenase Il inhibitors), antioxidants (such as Vitamin E and ginkolidesor), statins or p-glycoprotein (P-gp) inhibitors (such as cyclosporin A, verapamil, tamoxifen, quinidine, Vitamin E-TGPS, ritonavir, megestrol acetate, progesterone, rapamycin, 10,11-methanodibenzosuberane, phenothiazines, acridine derivatives such as GF120918, FK506, VX-710, LY335979 and PSC-833).

When the compounds are used in combination with other therapeutic agents, the compounds may be administered either sequentially or simultaneously by any convenient route.

The combinations referred to above may conveniently be presented for use in the form of a pharmaceutical formulation and thus pharmaceutical formulations comprising a combination as defined above together with a pharmaceutically acceptable carrier or excipient comprise a further aspect of the invention. The individual components of such

combinations may be administered either sequentially or simultaneously in separate or combined pharmaceutical formulations.

The compounds according to the invention may, for example, be formulated for oral, inhaled, intranasal, buccal, enteral, parenteral, topical, sublingual, intrathecal or rectal administration, preferably for oral administration.

Tablets and capsules for oral administration may contain conventional excipients such as binding agents, for example syrup, acacia, gelatin, sorbitol, tragacanth, mucilage of starch, cellulose or polyvinyl pyrrolidone; fillers, for example, lactose, microcrystalline cellulose, sugar, maize- starch, calcium phosphate or sorbitol; lubricants, for example, magnesium stearate, stearic acid, talc, polyethylene glycol or silica; disintegrants, for example, potato starch, croscarmellose sodium or sodium starch glycollate; or wetting agents such as sodium lauryl sulphate. The tablets may be coated according to methods well known in the art. Oral liquid preparations may be in the form of, for example, aqueous or oily suspensions, solutions, emulsions, syrups or elixirs, or may be presented as a dry product for constitution with water or other suitable vehicle before use. Such liquid preparations may contain conventional additives such as suspending agents, for example, sorbitol syrup, methyl cellulose, glucose/sugar syrup, gelatin, hydroxymethyl cellulose, carboxymethyl cellulose, aluminium stearate gel or hydrogenated edible fats; emulsifying agents, for example, lecithin, sorbitan mono-oleate or acacia; non-aqueous vehicles (which may include edible oils), for example almond oil, fractionated coconut oil, oily esters, propylene glycol or ethyl alcohol; or preservatives, for example, methyl or propyl p- hydroxy benzoates or sorbic acid. The preparations may also contain buffer salts, flavouring, colouring and/or sweetening agents (e.g. mannitol) as appropriate.

For buccal administration the compositions may take the form of tablets or lozenges formulated in conventional manner.

The compounds may also be formulated as suppositories, e.g. containing conventional suppository bases such as cocoa butter or other glycerides.

The compounds according to the invention may also be formulated for parenteral administration by bolus injection or continuous infusion and may be presented in unit dose form, for instance as ampoules, vials, small volume infusions or pre-filled syringes, or in multi-dose containers with an added preservative. The compositions may take such forms as solutions, suspensions, or emulsions in aqueous or non-aqueous vehicles, and may contain formulatory agents such as anti-oxidants, buffers, antimicrobial agents and/or tonicity adjusting agents. Alternatively, the active ingredient may be in powder form for constitution with a suitable vehicle, e.g. sterile, pyrogen-free water, before use. The dry solid presentation may be prepared by filling a sterile powder aseptically into

individual sterile containers or by filling a sterile solution aseptically into each container and freeze-drying.

When the compounds of the invention are administered topically they may be presented as a cream, ointment or patch.

The composition may contain from 0.1% to 99% by weight, preferably from 10 to 60% by weight, of the active material, depending on the method of administration.

The dose of the compound used in the treatment of the aforementioned disorders will vary in the usual way with the seriousness of the disorders, the weight of the sufferer, and other similar factors. However, as a general guide suitable unit doses may be 0.05 to 3000 mg; and such unit doses may be administered more than once a day, for example one, two, three or four times per day (preferably once or twice); and such therapy may extend for a number of weeks, months or years.

All publications, including but not limited to patents and patent applications, cited in this specification are herein incorporated by reference as if each individual publication were specifically and individually indicated to be incorporated by reference herein as though fully set forth.

Examples

Intermediates and compounds of the invention are characterised by their retention time (R.T.) in analytic LCMS. Analytical LCMS is conducted as described below:

• Column: Waters Atlantis 4.6mmx50mm ; 3 μm particle size

• Flow Rate: 3ml/min

• Injection Volume: 5μl • Temp: 30 ⁰ C

• UV Detection Range: 220 to 330nm •

Solvents: A. Water + 0.05% Formic acid

B: Acetonitrile + 0.05% Formic Acid

Gradient: Time B%

0.00 3

0.10 3

4.00 97

4.80 97

4.90 3

5.00 3

Also, where indicated, Mass Directed Auto-Purification or MDAP was carried out using a purification system supplied by Waters. The columns used were Waters Atlantis (19mm x 100mm or 30mm x 100mm). The solvent systems used comprised solvent A (water + 0.1% formic acid) and solvent B (acetonitrile + 0.1% formic acid) with gradients within the range 5-99% solvent B in solvent A.

Preparation of Intermediates

Description 1

Methyl 4-amino-3-nitrobenzoate (D1)

To a suspension of 4-amino-3-nitrobenzoic acid (available commercially from Aldrich) (50 g, 270 mmol, 1 equiv) in MeOH (600 ml) at room temperature was added SOCI ₂ (20 ml, 270 mmol, 1 equiv) dropwise. The resulting suspension was refluxed for 16 h then cooled to room temperature. The suspension was filtered off to give methyl-4-amino-3- nitrobenzoate (D1) (53g, 100%) as a yellow solid which was used in the next step without further purification. [M+H] ⁺ = 197.3, RT = 2.42 min.

Description 2 Methyl 4-amino-3-bromo-5-nitrobenzoate (D2)

To a solution of methyl-4-amino-3-nitrobenzoate (may be prepared as described in Description 1) (48 g, 244 mmol, 1 equiv) in CH ₂ CI ₂ (1.4 I) at room temperature was added bromine (16.3 ml, 318 mmol, 1.3 equiv). The resulting solution was refluxed for 2 h then another 6 ml (117 mmol, 0.5 equiv) of bromine were added and the solution was stirred for 1 h then cooled to room temperature. The organic phase was washed twice with a 10% aqueous sodium thiosulfite solution (200 ml) then with H ₂ O (200 ml), dried over MgSO ₄ and concentrated in vacuo to give methyl 4-amino-3-bromo-5-nitrobenzoate (D2) (66.2 g, 98%) as a yellow solid which was used in the next step without further purification. [M-H] ^" = 274.1 , RT = 2.90 min.

Description 3

Methyl 3-bromo-5-nitro-4-[(trifluoroacetyl)amino]benzoate (D3)

To a solution of methyl 4-amino-3-bromo-5-nitrobenzoate (may be prepared as described in Description 2) (46.4 g, 168 mmol, 1 equiv) in CH ₂ CI ₂ (1 I) at O ⁰ C was added pyridine (61 ml, 438 mmol, 2.6 equiv) then (CF ₃ CO) ₂ O (31 ml, 219 mmol, 1.3 equiv) and the resulting colourless solution was stirred for 1 h then concentrated in vacuo. The residue was dissolved in ethyl acetate (350 ml) and the organic phase was washed with H ₂ O (200 ml). The aqueous phase was extracted with ethyl acetate and the combined organic phases were washed with a 2N aqueous HCI solution and brine then dried over MgSO ₄ and concentrated in vacuo to give methyl 3-bromo-5-nitro-4- [(trifluoroacetyl)amino]benzoate (D3) (62.05 g, 99%) as a pale yellow solid which was used in the next step without further purification. [M+H] ⁺ = 372.2, RT = 2.92 min.

Description 4

Methyl 3-bromo-4-[(2i_yZ)-2-biiten-1 ^« yl(trifluoroacetyl)amino]-5-nitrobenzoate (D4)

To a solution of methyl 3-bromo-5-nitro-4-[(trifluoroacetyl)amino]benzoate (may be prepared as described in Description 3) (84.5 g, 228 mmol, 1 equiv) in CH ₃ CN (1 I) at room temperature under nitrogen was added K ₂ CO3 (37.7 g, 273 mmol, 1.2 equiv) and (2£/Z)-1-bromo-2-butene (available commercially from Aldrich) (30.5 ml, 296 mmol, 1.3 equiv) and the resulting suspension was refluxed for 2 h. (2E/Z)-1-bromo-2-butene (5 ml, 48 mmol, 0.2 equiv) was then added and the suspension refluxed for another hour then cooled to room temperature. The precipitate was filtered off and washed with ethyl acetate and the organic phase concentrated in vacuo. The residue was dissolved in ethyl acetate and the organic phase was washed with brine, dried over MgSO ₄ and concentrated in vacuo to give methyl 3-bromo-4-[(2E/Z)-2-buten-1- yl(trifluoroacetyl)amino]-5-nitrobenzoate (D4) as a brown oil (95 g, 98%) which was used in the next step without further purification. RT = 3.70 min.

Description 5

Methyl 3-bromo-4-[(2E/Z)-2-buten-1-ylamino]-5-nitrobenzoate (D5)

To a solution of methyl 3-bromo-4-[(2E/Z)-2~buten-1-yl(trifluoroacetyl)amino]-5- nitrobenzoate (67.5 g, 159 mmol, 1 equiv) (may be prepared as described in Description 4) in methanol (1 I) was added K ₂ CO ₃ (24.1 g, 175 mmol, 1.1 equiv) and the resulting red solution was stirred for 45 min at room temperature. Most of K ₂ CO ₃ was filtered off and most of methanol was removed in vacuo. When approximately 300 ml of methanol remained, a yellow precipitate was formed. This was filtered off and washed with methanol. The filtrate and washings were evaporated in vacuo and the residue was dissolved in ethyl acetate. The organic solution was washed with brine, dried over MgSO ₄ and concentrated in vacuo. Purification of the residue by flash chromatography on silica gel (/so-hexane/ethyl acetate : 9/1 then 4/1 ) gave methyl 3-bromo-4-[(2E/Z)-2- buten-1-ylamino]-5-nitrobenzoate (D5) as a red solid (8.9 g, 17%). The yellow precipitate was dissolved in ethyl acetate. The solution was washed with brine, dried over MgSO ₄ and concentrated in vacuo to give methyl 3-bromo-4-[(2£/Z)-2-buten-1-ylamino]-5- nitrobenzoate (D5) as a yellow solid (34.5 g, 66%). [M-H]- = 328.9, RT = 3.56 min.

Description 6

Methyl 3-amino-5-bromo-4-[(2£/2)-2-buten-1-ylamino]benzoate (D6)

To a yellow solution of methyl 3-bromo-4-[(2E/Z)-2-buten-1-ylamino]-5-nitrobenzoate (may be prepared as described in Description 5) (12 g, 36.6 mmol, 1 equiv) in glacial acetic acid (200 ml) was added iron (20.4 g, 366 mmol, 10 equiv) and the resulting mixture was vigorously stirred. The temperature slowly rose to 35 ⁰ C over 25 min then rapidly to 4O ⁰ C at which time the mixture was cooled with an ice bath. The temperature rose to 6O ⁰ C then went down to 3O ⁰ C. After 15 min, the colourless solution was diluted

with ethyl acetate (200 ml) and the resulting suspension was filtered through Hyflo. The insoluble residue was washed with ethyl acetate (200 ml) and the combined organic phases were concentrated in vacuo. The residue was dissolved in ethyl acetate and the organic phase was carefully washed with a saturated aqueous NaHCO ₃ solution, dried over MgSO ₄ and concentrated in vacuo to give methyl 3-amino-5-bromo-4-[(2£/Z)-2- buten-1-ylamino]benzoate (D6) (10.5 g, 96%) as a light brown solid which was used in the next step without further purification. [M+H] ⁺ = 301.0, RT = 3.34 min.

Description 7

Methyl 7-amino-3-ethyl-1H-indole-5-carboxylate (D7)

Methyl 3-amino-5-bromo-4-[(2£/Z)-2-buten-1-ylamino]benzoate (may be prepared as described in Description 6) (3 g, 10 mmol, 1 equiv), Na ₂ CO ₃ (2.65 g, 25 mmol, 2.5 equiv), tetra-n-butylammonium chloride (3 g, 11 mmol, 1.1 equiv) and Pd(OAc) ₂ (225 mg, 0.1 mmol, 0.1 equiv) were dissolved in dimethylformamide (60 ml) and the resulting mixture was stirred at 100 ⁰ C under nitrogen for 1 h then cooled to room temperature and concentrated in vacuo. The residue was dissolved in ethyl acetate and the organic phase was washed twice with a saturated aqueous NaHCO ₃ solution then with brine, dried over MgSO ₄ and concentrated in vacuo. Purification of the residue by flash chromatography on silica gel (/so-hexane/ethyl acetate: 4/1 to 1/1) gave methyl 7-amino-3-ethyl-1 H- indole-5-carboxylate (D7) (1.34 g, 61 %) as a pale yellow solid. [M+H] ⁺ = 219.0, RT = 2.68 min.

Description 8 Methyl 7-[(ethenylsulfonyl)amino]-3-ethyl-1H-indole-5-carboxylate (D8)

To a solution of methyl 7-amino-3-ethyl-1H-indole-5-carboxylate (may be prepared as described in Description 7) (1.03 g, 4.74 mmol, 1 equiv) in CH ₂ CI ₂ (20 ml) at room temperature were added pyridine (575 μl, 7.11 mmol, 1.5 equiv), DMAP (66 mg, 0.47 mmol, 0.1 equiv) and 2-chloroethanesulfonyl chloride (545 μl, 5.22 mmol, 1.1 equiv) and the resulting mixture was stirred for 5 min then diluted with ethyl acetate. The organic phase was washed with a 2N aqueous HCI solution, dried over MgSO ₄ and concentrated in vacuo. The residue was dissolved in CH ₂ CI ₂ (20 ml) and triethylamine

(1 ml, excess) was added and the resulting solution was stirred at room temperature for

16 h then diluted with ethyl acetate. The organic phase was washed with H ₂ O, 2N aqueous HCI solution and brine, dried over MgSO ₄ and concentrated in vacuo to give crude methyl 7-[(ethenylsulfonyl)amino]-3-ethyl-1H-indole-5-carboxylate (D8) (1.7 g, 110%) as a brown oil which was used in the next step without further purification. [M+H] ⁺ = 309.1 , RT = 3.29 min.

Description 9

Methyl 7-ethyl-3,4-dihydro-1 H-[1 ,2,5]thiadiazepino[3,4,5-Λ/|indole-9-carboxylate 2,2-dioxide (D9)

To a solution of methyl 7-[(ethenylsulfonyl)amino]-3-ethyl-1 H-indole-5-carboxylate (may be prepared as described in Description 8) (124 mg, 0.4 mmol, 1 equiv) in dimethylformamide (10 ml) at room temperature under nitrogen was added NaH (60% in mineral oil, 19 mg, 0.45 mmol, 1.2 equiv). After 5 min, the mixture was heated to 100 ⁰ C for 1 h and then cooled to room temperature. Ethanol (1 ml) was added and the solution was diluted with ethyl acetate. The organic phase was washed with 2N aqueous HCI solution, dried over MgSO ₄ and concentrated in vacuo to give methyl 7-ethyl-3,4-dihydro- 1H-[1 ,2,5]thiadiazepino[3,4,5-Λ/]indole-9-carboxylate 2,2-dioxide (D9) (95 mg, 77%) as a brown solid which was used in the next step without further purification. [M+H] ⁺ = 309.3, RT = 2.93 min.

Description 10

Methyl 7-ethyl-1-methyl-3,4-dihydro-1H-[1,2,5]thiadiazepino[3,4,5-/ 7/]indole-9- carboxylate 2,2-dioxide (D10) To a solution of methyl 7-ethyl-3,4-dihydro-1H-[1 ,2,5]thiadiazepino[3,4,5-/7/]indole-9- carboxylate 2,2-dioxide (may be prepared as described in Description 9) (191 mg, 0.621 mmol, 1 equiv) in dimethylformamide (10 ml) at room temperature under nitrogen were added NaH (60% in mineral oil, 50 mg, 1.24 mmol, 2 equiv) and, after 2 min, methyl iodide (46 μl, 0.74 mmol, 1.2 equiv). The resulting mixture was stirred at room temperature for 30 min then ethanol (1 ml) was added and the solution concentrated in vacuo. The residue was dissolved in ethyl acetate and the organic phase was washed with H ₂ O, dried over MgSO ₄ and concentrated in vacuo. Purification of the residue by flash chromatography on silica gel (/so-hexane/ethyl acetate : 1/1) gave methyl 7-ethyl-1- methyl-3,4-dihydro-1 H-[1 ,2,5]thiadiazepino[3,4,5-/7/lindole-9-carboxylate 2,2-dioxide (D10) (152 mg, 76%) as a white solid. [M+H] ⁺ = 323.1, RT = 3.24 min.

Description 11

7-Ethyl-1-methyl-3,4-dihydro-1H-[1,2,5]thiadiazepino[3,4, 5-/ϊ/|indole-9-carboxylic acid 2,2-dioxide (D11) To a solution of methyl 7-ethyl-1-methyl-3,4-dihydro-1H-[1 ,2,5]thiadiazepino[3,4,5- /7/]indole-9-carboxylate 2,2-dioxide (may be prepared as described in Description 10) (135 mg, 0.42 mmol, 1 equiv) in ethanol (20 ml) was added 2N aqueous NaOH solution (20 ml, 40 mmol, 95 equiv). The resulting mixture was stirred for 14 h then most of ethanol was removed in vacuo. The residue was extracted with diethyl ether. The aqueous layer was acidified using 2N aqueous HCI solution and the white precipitate formed was extracted twice with ethyl acetate. The combined organic solutions were dried over MgSO ₄ and concentrated in vacuo to give 7-ethyl-1-methyl-3,4-dihydro-1H- [1 ,2,5]thiadiazepino[3,4,5-/7/]indole-9~carboxylic acid 2,2-dioxide (D11) (74 mg, 57%) as a white solid, which was used in the next step without further purification. [M+H] ⁺ = 309.4, RT = 2.56 min

Description 12

1 ,1 -Dimethylethyl [(1 S,2/?)-2-hydroxy-1 -(phenylmethyl)-3-(tetrahydro-2H-pyran-4- ylamino)propyl]carbamate (D12)

((S)-(S)-1-Oxiranyl-2-pheny[-ethyl)-carbamic acid tert-butyl ester (10 g, 38 mmol, 1 equiv) (obtainable commercially from e.g. Chirex) was dissolved in ethanol (100 ml) and tetrahydro-2H-pyran-4~amine (available commercially from ABCR) (13 ml, 114 mmol, 3 equiv) was added. The resulting mixture was heated, under an atmosphere of nitrogen, for 12 h at reflux temperature. The mixture was cooled and the solvent was removed by evaporation in vacuo. The resulting white solid was washed with H ₂ O and then with diethyl ether before drying in vacuo to give 1 ,1-dimethylethyl[(1 S,2R)-2-hydroxy-1- (phenylmethyl)-3-(tetrahydro-2H-pyran-4-ylamino)propyl]carba mate (D12) (9.1 g, 66%).

[M+H] ⁺ = 365.2

Description 13

1 ,1 -Dimethylethyl [(1 S,2R)-2-hydroxy-3-({[3-(methyloxy)phenyl]methyl}amino)-1 - (phenylmethyl)propyl]carbamate (D13)

1 , 1 -Dimethylethyl [(1S,2R)-2-hydroxy-3-({[3-(methyloxy)phenyl]methyl}amino)-1- (phenylmethyl)propyl]carbamate (D13) was obtained from ((S)-(S)-I -Oxiranyl-2-phenyl- ethyl)-carbamic acid tert-butyl ester (obtainable commercially from e.g. Chirex) using an analogous process to that described in Description 12 using {[3- (methyloxy)phenyl]methyl}amine (available commercially from Aldrich) instead of tetrahydro-2/-/-pyran-4-amine. [M+H]+ = 401.1 RT = 2.5 min

Description 14 (2/?,3S)-3-Amino-4-phenyl-1 -(tetrahydro-2H-pyran-4-ylamino)-2-butanol di- hydrochloride (D14)

1 ,1-Dimethylethyl[(1 S,2R)-2-hydroxy-1-(phenylmethyl)-3-(tetrahydro-2H-pyran-4- ylamino)propyl]carbamate (may be prepared as described in Description 12) (9.1 g, 25 mmol, 1 equiv) was dissolved in methanol (70 ml) and then a 4M solution of HCI in diethyl ether (60 ml, excess) was added. The resulting mixture was stirred for 3 h at room temperature and then the solvents were removed by evaporation in vacuo. The resulting residue was washed with ethyl acetate and then with diethyl ether before drying in vacuo to give (2/?,3S)-3-amino-4-phenyl-1-(tetrahydro-2H-pyran-4-ylamino)~ 2- butanol di-hydrochloride (D14) as a white solid (7.4g, 88%).

Description 15

(2R3S)-3-Amino-4-phenyl-1-(tθtrahvdro-2H-pyran-4~ylamino )-2-butanol bis(4- methylbenzenesulfonate) salt (D15) 1 ,1-Dimethylethyl[(1 S,2R)-2-hydroxy-1-(phenylmethyl)-3-(tetrahydro-2H-pyran-4- ylamino)propyl]carbamate (may be prepared as described in Description 12) (1.2 g, 25 mmol, 1 equiv) was dissolved in acetonitrile (15 ml) and then p-toluenesulphonic acid monohydrate (1.88 g, 3 equiv) was added. The resulting mixture was stirred for 6 h at

room temperature and then the precipitated solid was collected by filtration. The solid was washed with diethyl ether before drying in vacuo to give (2f?,3S)-3-amino-4-phenyl- 1-(tetrahydro-2H-pyran-4-ylamino)-2-butanol bis(4-methylbenzenesulfonate) salt (D15) as a white solid (U g ₁ ), [M+H] ⁺ = 265.5, RT = 0.91 min

Description 16

(2/?,3S)-3-Amino-1-({[3-(methyloxy)phenyI]methyl}amino)-4 -phenyl-2-butanol di~ hydrochloride (D16) (2R,3S)-3-Amino-1-({[3-(methyloxy)phenyl]methyl}amino)-4-phe nyl-2-butanol di- hydrochloride (D16) was obtained from 1 ,1-dimethylethyl [(1 S,2R)-2-hydroxy-3-({[3- (methyloxy)phenyl]methyl}amino)-1-(phenylmethyl)propyl]carba mate (may be prepared as described in Description 13) using an an analogous process to that described in Description 14.

Description 17

(2f?,3S)-3-Amino-1-({[3-(methyloxy)phenyl]methyl}amino)-4 -phenyI-2-butanol bis(4j; methylbenzenesulfonate) salt (D17) (2R,3S)-3-Amino-1-({[3-(methyloxy)phenyl]methyl}amino)-4-phe nyl-2-butanol bis(4- methylbenzenesulfonate) salt (D 17) was obtained from 1 ,1-dimethylethyl [(1 S,2f?)-2- hydroxy-3-({[3-(methyloxy)phenyl]methyl}amino)-1-(phenylmeth yl)propyl]carbamate (may be prepared as described in Description 13) using an an analogous process to that described in Description 14. LC/MS data: [M+H]+ = 301.1 retention time = 1.6 min

Description 18

7-Ethyl-Λ/-[(1S,2/?)-2-hydroxy-1-(phenylmethyl)-3-(tetra hydro-2H-pyran-4- ylaminoJpropyll-i-methyl-S^-dihydro-IH-fi^^lthiadiazepinoISA S-Λ/lindole-θ- carboxamide 2,2-dioxide (D18) To a solution of 7-ethyl-1-methyl-3,4-dihydro-1H-[1 ,2,5]thiadiazepino[3,4,5-Λ/]indole-9- carboxylic acid 2,2-dioxide (may be prepared as described in Description 11) (62 mg, 0.2 mmol, 1 equiv) in dimethylformamide (5 ml) at room temperature was added (2R,3S)-3- amino-4-phenyl-1-(tetrahydro-2W-pyran-4-ylamino)-2-butanol bis(4- methylbenzenesulfonate) salt (may be prepared as described in Description 15) (67 mg, 0.2 mmol, 1 equiv), 1-(3-dimethylaminopropyl)-3-ethyl-carbodiimide hydrochloride (available commercially from Lancaster)(46 mg, 0.24 mmol, 1.2 equiv), 1- hydroxybenzotriazole hydrate (37 mg, 0.24 mmol, 1.2 equiv) and 4-ethylmorpholine (available commercially from Aldrich) (152 μl, 1.2 mmol, 6 equiv). The resulting mixture was stirred for 12 h then concentrated in vacuo. The residue was diluted with ethyl acetate and the organic phase washed with a saturated aqueous NaHCO ₃ solution, dried over MgSO ₄ and concentrated in vacuo. Purification of the residue by flash chromatography on silica gel (CH ₂ CI ₂ /methanol :100/0 to 98/2) gave 7-ethyl-Λ/-[(1 S,2R)-

2-hydroxy-1 -(phenylmethyl)-3-(tetrahydro-2H-pyran-4-ylamino)propyl]-1 -methyl-3,4- dihydro-1H-[1 ,2,5]thiadiazepino[3,4,5-/7/]indole-9-carboxamide 2,2-dioxide (D18) as a gum (78 mg, 70%) [M+H] ⁺ = 555.4, RT = 2.30 min 7-Ethyl-Λ/-[(1 S,2R)-2-hydroxy-1-(phenylmethyl)-3-(tetrahydro-2/-/-pyran-4- ylamino)propyl]-1 -methyl-3,4-dihydro-1 H-[1 ,2,5]thiadiazepino[3,4,5-/i/]indole-9- carboxamide 2,2-dioxide (D18) may also be prepared using (2f?,3S)-3-Amino-4-phenyl- 1-(tetrahydro-2H-pyran-4-ylamino)-2-butanol c//-hydrochloride (may be prepared as described in Description 14) in place of (2R,3S)-3-amino-4-phenyl-1-(tetrahydro-2H- pyran-4-ylamino)-2-butanol bis(4-methylbenzenesulfonate) salt.

Description 19

7-Ethyl-Λ/-[(1S,2/?)-2-hydroxy-3-({[3-(methyloxy)phenyl] methyl}amino)-1- (phenylmethyl)propyl]-1 -methyl-3,4-dihydro-1 H-[1 ,2,5]thiadiazepino[3,4,5-/7/|indole- 9-carboxamide 2,2-dioxide (D19)

7-Ethyl-Λ/-[(1S,2R)-2-hydroxy-3-({[3-(methyloxy)phenyl]m ethyl}amino)-1- (phenylmethyl)propyl]-1 -methyl-3,4-dihydro-1 H-[1 ,2,5]thiadiazepino[3,4,5-/}/]indole-9- carboxamide 2,2-dioxide (D19) was obtained from (2R,3S)-3-amino-1-({[3- (methyloxy)phenyl]methyl}amino)-4-phenyl-2-butanol bis(4-methylbenzenesulfonate) salt (may be prepared as described in Description 17) and 7-ethyl-1-methyl-3,4-dihydro-1H- [1,2,5]thiadiazepino[3,4,5-/7/]indole-9-carboxylic acid 2,2-dioxide (may be prepared as described in Description 11 ) using an analogous process to that described in Description 16. [M+H] ⁺ = 591.2, RT = 2.63 min 7-Ethyl-Λ/-[(1 S,2R)-2-hydroxy-3-({[3-(methyloxy)phenyl]methyl}amino)-1 -

(phenylmethyl)propyl]-1 -methyl-3,4-dihydro-1 H-{\ ,2,5]thiadiazepino[3,4,5-/7/]indole-9- carboxamide 2,2-dioxide (D19) may also be prepared using (2R,3S)-3-Amino-1-({[3- (methyloxy)phenyl]methyl}amino)-4-phenyl-2-butanol (//-hydrochloride (may be prepared as described in Description 16) in place of (2R,3S)-3-Amino-1-({[3- (methyloxy)phenyl]methyl}amino)-4-phenyl-2-butanol bis(4-methylbenzenesulfonate) salt.

Description 20

1,1-DimethylethyI ((2/?,3S)-3-{[(7-ethyl-1-methyl-2,2-dioxido-3,4-dihydro-1H- [1,2,5]thiadiazepino[3,4,5-/7/]indol-9-yl)carbonyI]amino}-2- hydroxy-4- phenylbutyl)tetrahydro-2H-pyran-4-ylcarbamate (D20)

To a solution of 7-ethyl-N-[(1 S,2f?)-2-hydroxy-1-(phenylmethyl)-3-(tetrahydro-2/-/-pyran- 4-ylamino)propyl]-1 -methyl-3,4-dihydro-1 H-[1 ,2,5]thiadiazepino[3,4,5-/7/]indole-9- carboxamide 2,2-dioxide (may be prepared as described in Description 18) (78 mg, 0.14 mmol, 1 equiv) in CH ₂ CI ₂ (3 ml) at room temperature was added bis(1 ,1-dimethylethyl) dicarbonate (available commercially from Aldrich) (34 mg, 0.154 mmol, 1.1 equiv) and the resulting solution was stirred then concentrated in vacuo. Purification of the residue

by flash chromatography on silica gel (/so-hexane/ethyl acetate: 1/2 then 1/3) gave 1 ,1- dimethylethyl((2f?,3S)-3-{[(7-ethyl-1-methyl-2 _I 2-clioxiclo-3,4-dihydro-1H- [1 ,2,5]thiadiazepino[3,4,5-ft/]indol-9-yl)carbonyl]amino}-2-hy droxy-4- phenylbutyl)tetrahydro-2H-pyran-4-ylcarbamate (D20) (77 mg, 85%) as a white foam. [M+H] ⁺ = 655.5, RT = 3.34 min

Description 21 i.i-Dimethylethyl ^fϊ.SSJ-S-dtT-ethyl-i-methyl-Z^-dioxido-a^-dihydro-IH- [1,2,5]thiadiazβpino[3,4,5-/i/]indol-9-yl)carbonyl]amino}-2 -hydroxy-4- phenylbutyl){[3-(methyloxy)phenyl]methyl}carbamate (D21)

1 ,1 -Dimethylethyl ((2R,3S)-3-{[(7-ethyl-1 -methyl-2,2-dioxido-3,4-dihydro-1 H- [1,2,5]thiadiazepino[3,4,5-/7/jindol-9-yl)carbonyl]amino}-2- hydroxy-4-phenylbutyl){[3- (methyloxy)phenyl]methyl}carbamate (D21) was obtained from 7-ethyl-N-[(1 S,2f?)-2- hydroxy-3-({[3-(methyloxy)phenyl]methyl}amino)-1-(phenylmeth yl)propyl]-1-methyl-3,4- dihydro-1/-/-[1 ,2,5]thiadiazepino[3,4,5-/)/]indole-9-carboxarnide 2,2-dioxide (may be prepared as described in Description 19) using an analogous process to that described in Description 20.

[M+H] ⁺ = 691.5, RT = 3.69 min

Description 22

1, 1 -Dimethylethyl ((3S)-3-{[(7-ethyl-1-methyl-2,2-dioxido-3,4-dihydro-1 H- [1,2,5]thiadiazepino[3,4,5-/7/]indol-9-yl)carbonyl]amino}-2- oxo-4- phenylbutyl)tetrahydro-2H-pyran-4-ylcarbamate (D22)

To a solution of 1 ,1 -dimethylethyl ((2R,3S)-3-{[(7-ethyM-methyl-2,2-dioxido-3,4-dihydro- 1 H-[1 ,2,5]thiadiazepino[3,4,5-/7/]indol-9-yl)carbonyl]amino}-2-hy droxy-4- phenylbutyl)tetrahydro-2H-pyran-4-ylcarbamate (may be prepared as described in Description 20) (73 mg, 0.112 mmol, 1 equiv) in CH ₂ CI ₂ (4 ml) under nitrogen at room temperature was added Dess-Martin periodinane (71 mg, 0.168 mmol, 1.5 equiv). After 40 min, a saturated aqueous NaHCO ₃ solution containing 10% w/w Na ₂ S ₂ O ₃ was added and the biphasic mixture stirred vigorously for 40 min. The two layers were separated and the organic phase dried over MgSO ₄ then concentrated in vacuo. Purification of the residue by flash chromatography on silica gel (/so-hexane/ethyl acetate: 3/2) gave 1 ,1- dimethylethyl ((3S)-3-{[(7-ethyl-1 -methyl-2,2-dioxido-3,4-dihydro-1 H-

[i^.δJthiadiazepinoP^.S-Λ/Iindol-θ-yOcarbonylJaminoϊ^ -oxo^-phenylbutylJtetrahydro- 2H-pyran-4~ylcarbamate (D22) (60 mg, 82%) as a pale yellow gum. [M-H]- = 651.4, RT = 3.48 min.

Description 23

1 ,1 -Dimethylethyl ((3S)-3-{[(7-ethyl-1 -methyl-2,2-dioxido-3,4-dihydro-1 H- [1,2,5]thiadiazepino[3,4,5-/7/]indol-9-yl)carbonyl]amino}-2- oxo-4-phenylbutyl){[3- (methyloxy)pheny[]methyl}carbamate (D23)

1 , 1 -Dimethylethyl ((3S)-3-{[(7-ethyl-1 -m ^β thyl-2,2-dioxido-3,4-dihydro-1 i^

[i^.δlthiadiazepino^^.δ-Λ/linclol-θ-yOcarbonyllaminoJ ^-oxo^-phenylbutyl)!^- (methyloxy)phenyl]methyl}carbamate (D23) was obtained from 1 ,1-dimethylethyl ((2R,3S)-3-{[(7-ethyl-1 -methyl-2,2-dioxido-3,4-dihydro-1 H-[1 ,2,5]thiadiazepino[3,4,5- /7/]indol-9-yl)carbonyl]amino}-2~hydroxy-4-phenylbutyl){[3-

(methyloxy)phenyl]methyl}carbamate (may be prepared as described in Description 21) using an analogous process to that described in Description 22. [M-H]- = 687.4, RT = 3.85 min

Example 1

7-Ethyl-1 -methyl-W-[(1 S)-2-oxo-1 -(phenylmethyl)-3-(tetrahydro-2H-pyran-4- ylamino)propyl]-3,4-dihydro-1H-[1,2,5]thiadia2epino[3,4,5-/7 /]indole-9-carboxamide 2,2-dioxide (E1)

To a solution of 1 ,1 -dimethylethyl ((3S)-3-{[(7-ethyl-1 -methyl-2,2-dioxido-3,4-dihydro-1 H- [1 ,2,5]thiadiazepino[3,4,5-/?ι]indol-9-yl)carbonyl]amino}-2-o xo-4-phenylbutyl)tetrahydro- 2H-pyran-4-ylcarbamate (may be prepared as described in Description 22) (55 mg, 0.084 mmol, 1 equiv) in dioxane (2.4 ml) was added 4-methylbenzenesulfonic acid hydrate (48 mg, 0.252 mmol, 3 equiv) and the resulting mixture was stirred at room temperature for 16 h. The mixture was partitioned between ethyl acetate and a saturated aqueous NaHCO ₃ solution. The two phases were separated and the organic phase washed twice with a saturated aqueous NaHCO ₃ solution, dried on MgSO ₄ and concentrated in vacuo. Purification of the residue by Mass Directed Autopreparation gave 7-ethyl-1 -methyl- A/-[(1 S)-2-oxo-1 -(phenylmethyl)-3-(tetrahydro-2H-pyran-4- ylamino)propyl]-3,4~dihydro-1 H-[1 ,2,5]thiadiazepino[3,4,5-ft/]indole-9-carboxamide 2,2- dioxide (E1) (16 mg, 35%) as a white foam. [M-H] ^" = 553.4, RT = 2.27 min.

Example 2

7-Ethyl-1 -methyl-N-[(1 S)-3-({[3-(methyloxy)phenyl]methyl}amino)-2-oxo-1 - (phenylmethyl)propyl]-3,4-dihydro-1 H-[1 ,2,5]thiadiazepino[3,4,5-/?i]indole-9- carboxamide 2,2-dioxide (E2):

7-Ethyl-1 -methyl-Λ/-[(1 S)-3-({[3-(methyloxy)phenyl]methyl}amino)-2-oxo-1 - (phenylmethyl)propyl]-3 _> 4-clihyclro-1H-[1,2,5]thiacliazepino[3 ₎ 4,5-/?/]indole-9-carboxamide 2,2-dioxide (E2) was obtained from 1 ,1-dimethylethyl ((3S)-3-{[(7-ethyl-1-methyl-2,2- dioxido-3,4-dihydro-1 H-[1 ,2,5]thiadiazepino[3,4,5-/7/]indol-9-yl)carbonyl]amino}-2-ox o-4- phenylbutyl){[3-(methyloxy)phenyl]methyl}carbamate (may be prepared as described in Description 23) using an analogous process to that described in Example 1 (E1 ). [M+H] ⁺ = 589.4, RT = 2.73 min.

Compounds of the invention may be tested for in vitro biological activity in accordance with the following assays:

Asp-2 inhibitory assay

For each compound being assayed, in a 384 well plate, is added:- a) 0.5μl of a DMSO solution of the test compound (IC ₅₀ curve uses eleven 1 in 3 serial dilutions from 100 μM). b) 10 μl of substrate (FAM-[SEVNLDAEFK]-TAMRA ) solution in buffer A. This is prepared by diluting 2ml of a 2mM DMSO solution of the substrate into 400ml of buffer A (10OmM Sodium acetate pH = 4.5, 1 I MiIIi-Q water, 0.06% Triton X-100 (0.5 ml/l) , pH adjusted to 4.5 using glacial acetic acid). Aminomethyl fluorescein (FAM) and tetramethyl rhodamine (TAMRA) are fluorescent molecules which co-operate to emit fluorescence at 535nm upon cleavage of the SEVNLDAEFK peptide. c) 10 μl enzyme solution. This is prepared by performing a 1 in 1750 dilution of a 3.5 μM enzyme stock in buffer B (100 mM Sodium acetate pH 4.5, 40 mM Sodium chloride, 10% (v/v) Glycerol, 0.2% (w/v) CHAPS).

Blank wells (enzyme solution replaced by buffer) are included as controls on each plate. Wells are incubated for 4h at room temperature and fluorescence read using an LJL analyst spectrophotometer ( 485nm excitation, 535nm emission).

(II) Cathepsin D inhibitory assay

For each compound being assayed, in a 384 well plate, is added:- a) 0.5μl of a DMSO solution of the test compound (IC ₅₀ curve uses eleven 1 in 3 serial dilutions from 100 μM). b) 10 μl of substrate (FAM-[SEVNLDAEFK]-TAMRA ) solution in buffer. This is prepared by diluting 2ml of a 2mM DMSO solution of the substrate into 400ml of buffer A (10OmM

Sodium acetate pH = 4.5, 1 I MiIIi-Q water, 0.06% Triton X-100 (0.5 ml/I) , pH adjusted to 4.5 using glacial acetic acid). c) 10 μl enzyme solution. This is prepared by performing a 1 in 2000 dilution of a 150 unit/ml (in 2OmM MES pH4.5, 15OmM NaCI, 0.5% (v/v) Triton X-100, 2mM EDTA) solution of Cathepsin D in buffer A (prepared as above).

Blank wells (enzyme solution replaced by buffer) are included as controls on each plate. Wells are incubated for 1h at room temperature and fluorescence read using an LJL analyst spectrophotomer ( 485 nm excitation, 535nm emission).

Pharmacological Data

The compounds of Examples E1-2 were tested in the Asp-2 inhibitory assay and the Cathepsin D inhibitory assay and exhibited inhibition <10μM in the Asp-2 inhibitory assay and > 10 fold selectivity for Asp2 over CatD.

Abbreviations

DMF dimethylformamide

DMSO dimethylsulfoxide

DMAP 4-(dimethylamino)pyridine

DABCO 1 ,4-diazabicyclo [2.2.2] octane

DME dimethyl ether

THF tetrahydrofuran

HOBT N-hydroxybenzotriazole

FAM carboxyfluorescein

TAMRA carboxytetramethylrhodamine

[ ] single amino acid letter code relating to peptide sequence