NOVEL DIPEPTIDYL PEPTIDASE IV (DP-IV) INHIBITORS AS ANTI-DIABETIC AGENTS
The present invention relates to novel compounds that are prodrugs of inhibitors of dipeptidyl peptidase IV. The compounds are useful in the treatment of, inter alia, type 2 diabetes and impaired glucose tolerance.
BACKGROUND
The enzyme dipeptidyl peptidase IV, herein abbreviated DP-IV (and elsewhere as DAP-IV or DPP-IV) and also known by the classification EC.3.4.14.5, is a serine protease that cleaves the N-terminal dipeptide from peptides that begin with the sequence H-Xaa-Pro (where Xaa is any amino acid, although preferably a lipophilic one, and Pro is proline). It will also accept as substrates peptides that begin with the sequence H-Xaa-Ala (where Ala is alanine). DP-IV was first identified as a membrane-bound protein. More recently a soluble form has been identified.
Initial interest in DP-IV focussed on its role in the activation of T lymphocytes. DP-IV is identical to the T cell protein CD26. It was proposed that inhibitors of DP-IV would be capable of modulating T cell responsiveness, and so could be developed as novel immunomodulators. It was further suggested that CD26 was a necessary co-receptor for HIV, and thus that DP-IV inhibitors could be useful in the treatment of AIDS.
Attention was given to the role of DP-IV outside the immune system. It was recognised that DP-IV has a key role in the degradation of several peptide hormones, including growth hormone releasing hormone (GHRH) and glucagon-like peptide-1 and -2 (GLP-1 and GLP-2). Since GLP-1 is known to have a potentiating effect on the action of insulin in the control of post-prandial blood glucose levels it is clear that DP-IV inhibitors might also be usefully employed in the treatment of type II diabetes and impaired glucose tolerance. At least two DP-IV inhibitors are currently undergoing clinical trials to explore this possibility.
Several groups have disclosed inhibitors of DP-IV. While some leads have been found from random screening programs, the majority of the work in this field has been directed towards the investigation of substrate analogues. Inhibitors of DP-IV that are substrate analogues are disclosed in, for example, US 5,462,928, US 5,543,396,
WO95/15309 (equivalent to US 5,939,560 and EP 0731789), W098/19998 (equivalent to US 6,011,155), W099/46272 and W099/61431. The most potent inhibitors are aminoacyl pyrrolidine boronic acids, but these are unstable and tend to cyclise, while the more stable pyrrolidine and thiazolidine derivatives have a lower affinity for the enzyme and so would require large doses in a clinical situation. Pyrrolidine nitriles appear to offer a good compromise since they have both a high affinity for the enzyme and a reasonably long half-life in solution as the free base. There remains, however, a need for inhibitors of DP-IV with improved properties.
SUMMARY OF THE INVENTION
The present invention relates to a series of prodrugs of inhibitors of DP-IV with improved properties. The compounds can be used for the treatment of a number of human diseases, including impaired glucose tolerance and type II diabetes. Accordingly, the invention further relates to the use of the compounds in the preparation of pharmaceutical compositions, to such compositions per se, and to the use of such compositions in human therapy. The compounds of the invention are described by general formula 1.
(Formula Removed)
In this general formula R1 is H or CN; R2 is selected from CH2R5, CH2CH2R5 and C(R3)(R4)-X2-(CH2)aR5; R3 and R4 are each independently selected from H and Me; R5 is selected from CON(R6)(R7), N(R8)C(=O)R9, N(R8)C(=S)R9, N(R8)SO2R10 and N(Ra)R10; R6 and R7 are each independently R11(CH2)b or together they are -(CH2)2-Z-(CH2)2- or -CH2-o-C6H4-Z-CH2-; R8 is H or Me; R9 is selected from R11(CH2)b, R11(CH2)bO and N(R6)(R7); R10 is R11(CH2)b; R11 is selected from H, alkyl, optionally substituted aryl, optionally substituted aroyl, optionally substituted arylsulphonyl and optionally substituted heteroaryl; R12 is selected from H2NCH(R13)CO, H2NCH(R14)CONHCH(R15)CO, C(R16)=C(R17)COR'15 and R19OCO; R13, R14 and R15 are selected from the side chains of the proteinaceous amino acids; R16 is selected from H, lower alkyl (C1-C6) and phenyl; R17 is selected from H and lower alkyl (C1- C6); R18 is selected from H, lower alkyl (C1- C6), OH, O-(lower alkyl (C1- C6)) and phenyl; R19 is
selected from lower alkyl (C1-C6), optionally substituted phenyl and R20C(=O)OC(R21)(R22); R20, R21 and R22 are each independently selected from H and lower alkyl (C1-C6); Z is selected from a covalent bond, -(CH2)C-, -O-, -SOd and -N(R10)-; X1 is S or CH2; X2 is O. S or CH2; a is 1, 2 or 3; b is 0 - 3; c is 1 or 2; and d is 0,1 or 2.
DETAILED DESCRIPTION OF THE INVENTION
In a first aspect, the present invention relates to a series of novel compounds that are prodrugs of inhibitors of DP-IV with improved properties. The compounds of the invention are described by general formula 1.
(Formula Removed)
In this general formula R1 is either a hydrogen atom (H) or a nitrile group (-CN) and X1 is either a sulphur atom (S) or CH2. In one preferred embodiment of the invention, R1 is H. In another preferred embodiment, R1 is CN.
R2 is selected from a group according to CH2R5, a group according to CH2CH2R5 and a group according to C(R3)(R4)-X2-(CH2)aR5, where R3 and R4 are each independently selected from H and a methyl group (Me), X2 is O, S or CH2 and a is 1, 2 or 3. Preferably R2 is selected from a group according to CH2CH2RS and a group according to C(R3)(R4)-X2-(CH2)aR5. More preferably R2 is selected from a group according to CH2CH2R5 and a group according to C(R3)(R4)-X2-(CH2)aR5 where R3 and R4 are both H, X2 is CH2 and a is 1 or 2. Most preferably R2 is selected from a group according to CH2CH2CH2R5 and a group according to CH2CH2CH2CH2R5.
R5 is selected from a group according to CON(R6)(R7), a group according to N(RB)C(=O)R9, a group according to N(R8)C(=S)R9. a group according to N(R8)SO2R10 and a group according to N(RB)R10. In one preferred embodiment of the invention, R5 is a group according to CON(R8)(R7). In another preferred embodiment, R5 is selected from a group according to N(R8)C(=O)R9, a group according to N(R8)C(=S)R9, a group according to N(Ra)SO2R10 and a group according to N(R8)R10.
R6 and R7 may each independently a group according to R11(CH2)b, where b is 0 - 3. Alternatively they may together be a chain -(CH2)2-Z-(CH2)2- or -CH2-o-C6H4-Z-CH2-, where Z is selected from a covalent bond, -(CH2)C-, -O-, -SOd- and -N(R10)-, c is 1 or 2; and d is 0,1 or 2, such that, together with the nitrogen atom to which they are attached, they form a five-, six- or seven-membered ring.
R8 is H or Me.
R9 is selected from a group according to R11(CH2)b, a group according to R1,(CH2)bO and a group according to N(R6)(R7).
R10 is a group according to R11(CH2)b.
R11 is selected from H, alkyl, optionally substituted aryl, optionally substituted aroyl, optionally substituted arylsulphonyl and optionally substituted heteroaryl.
The term alkyl, as used herein, denotes saturated hydrocarbon groups with between 1 and 10 carbon atoms, including straight-chain, branched and mono- and polycycloalkyl groups, such as methyl, ethyl, propyl, isopropyl, n-butyl, tert-butyl, cyclopentyl, cyclohexyl, cyclohexylmethyl, 2-cyclohexyl-2-propyl, bicyclo[2.2.2]octyl and the like.
The term aryl, as used herein, denotes monocyclic and fused bicyclic aromatic groups, including carbocyclic groups, such as phenyl and naphthyl, and heteroaryl groups with up to three heteroatoms selected from nitrogen, oxygen and sulphur, such as pyrrolyl, furyl, thienyl, pyrazolyl, imidazolyl, oxazolyl, isothiazolyl, pyridyl, pyrimidinyl, indolyl, quinolinyl and the like. Unless otherwise specified, an aryl, aroyl, arylsulphonyl or heteroaryl group may optionally be substituted with up to three groups independently selected from alkyl, OH, alkoxy, O-alkyl, CI, F, Br, NH2, amino (including alkylamino NH-alkyl and dialkylamino N(alkyl)2), CO2H, CO2-alkyl, CONH2, CONH-alkyl. CON(alkyl)2, acyl, carboxy, carboxyalkyl, carboxamido, N02 and CN.
R12 is selected from a group according to H2NCH(R13)CO, a group according to H2NCH(R14)CONHCH(R15)CO, a group according to C(R16)=C(R17)COR18 and a group according to R19OCO. In one preferred embodiment of the invention R12 is selected
from a group according to H2NCH(R13)CO and a group according to H2NCH(R14)CONHCH(R15)CO. In another preferred embodiment of the invention R12 is a group according to R19OCO.
R13. R14 and R15 are selected from the side chains of the proteinaceous amino acids, as listed in the following Table.
(Table Removed)
R16 is selected from H, lower alkyl (C1- C6 alkyl) and phenyl.
R17 is selected from H and lower alkyl (C1- C6).
R18 is selected from H, lower alkyl (C1-C6), OH, O-(lower alkyl (C1-C6)) and phenyl.
R19 is selected from lower alkyl (C1-C6), optionally substituted phenyl and R20C(=O)OC(R21)(R22).
R20, R21 and R22 are each independently selected from H and lower alkyl (C1-C6).
In a preferred embodiment, X1 is CH2and R1 is CN. For this embodiment, preferred R5 groups are CON(R6)(R7), N(R8)C(=O)R9, N(R8)C(=S)R9 and N(R8)R10. In another preferred embodiment, X1 is CH2and R1 is H. In another preferred embodiment X1 is S. In a further preferred embodiment X1 is S and R1 is H.
Preferred compositions according to the invention may have improved activity and/or improved pharmacological profile. Preferred compositions may have in vivo stability characteristics which make them particularly suitable for use as pro-drugs.
Certain of the compounds of the present invention have acidic or basic properties and so can exist as salts. Insofar as such salts are non-toxic and otherwise pharmaceutical^ acceptable, they are included within the scope of the invention. Examples of such salts include, but are not limited to, the acetate, hydrochloride, sulphate, phosphate and benzoate salts of basic compounds, and the sodium, potassium and tetra-alkyl ammonium salts of acidic compounds.
Following administration, the compounds of the present invention are transformed into compounds according to general formula 2. These compounds are potent inhibitors of dipeptidyl peptidase IV.
(Formula Removed)
Accordingly, the compounds of the invention can be used for the treatment of a number of human diseases, including impaired glucose tolerance and type II diabetes. Further aspects of the invention therefore relate to the use of the compounds in the preparation of pharmaceutical compositions, to such compositions per se, and to the use of such compositions in human therapy.
The compounds of the present invention may be prepared according to methods that are well known in the field of organic chemistry, and particularly peptide chemistry. One strategy is to prepare the corresponding primary amine according to general formula 2 and then derivatise this.
(Formula Removed)
When R12 is H2NCH(R13)CO then the final transformation may be accomplished in two steps by the reaction of 2 with a protected amino acid derivative followed by a deprotection step.
(Formula Removed)
In the above scheme, PG is a protecting group such as tert-butyloxycarbonyl (BOC), 9-fluorenylmethyloxycarbonyl (FMOC) or benzyloxycarbonyl.
When R12 is H2NCH(R14)CONHCH(R15)CO then the final transformation may be accomplished analogously by the reaction of 2 with a protected dipeptide derivative followed by a deprotection step, or in a slightly longer way with two cycles of coupling and deprotection.
When R12 is C(R1$)=C(R17)COR18 then the final transformation may be accomplished by the reaction of 2 with a suitable 1,3-dicarbonyl compound.
(Formula Removed)
When R12 is R19OCO then the final transformation may be accomplished by the reaction of 2 with a suitable active carbonic acid half ester derivative, such as a chloroformate or a para-nitrophenyJ carbonate.
(Formula Removed)
The intermediate 2 may be prepared by the coupling of a protected amino acid with a pyrrolidine or thiazolidine derivative, followed by a deprotection step.
(Formula Removed)
Alternatively, it may be more convenient to elaborate the functionality of R2 after the assembly of the backbone of 2.
These general methods are further illustrated in the following non-limiting Examples.
EXAMPLE 1
(2S)-1-[Nα-(1'-Acetoxyethoxycarbonyl)-N-pyrazinyl-2-carbonyl)-L-omithinyl]-
pyrrolidine-2-carbonitrile
(Formula Removed)
1A. N-(2-Nitrobenzenesulphenyl)-L-proline
L-Proline (25g, 217mmol) was dissolved in 2M NaOH (110ml, 220mmol) and dioxan (120ml). A solution of 2-nitrobenzenesulphenyl chloride (42g, 222mmol) in dioxan (60ml) was slowly added at the same time as 2M NaOH (110ml, 220mmol). The mixture was stirred for 2 hours at room temperature then poured into water (500ml). The solid was removed by filtration. The pH of the filtrate was adjusted to pH3 with 2M HCI and the solution was extracted with ethyl acetate (3 x 500ml). The combined organic extracts were washed with water (4 x 200ml) and brine (1 x 200ml), dried (Na2SO4) and evaporated in vacuo to give an orange solid identified as N-(2-nitrobenzenesulphenyl)-L-proline (58.1g, 217mmol. 100%).
1B. N-(2-Nitrobenzenesulphenyl)-L-proline succinimidyl ester
N-(2-Nitrobenzenesulphenyl)-L-proline (57.9g, 216mmol) was dissolved in CH2CI2/DMF (9:1, 500ml). N-Hydroxysuccinimide (37.3g, 324mmol) and water-soluble carbodiimide (51.8g, 260mmol) were added. The mixture was stirred for 18 hours at room temperature then the solvent was removed in vacuo and the residue was taken up in ethyl acetate (1000ml). The solution was washed with water (4 x 200ml) and brine (1 x 200ml), dried (Na2SO.) and evaporated in vacuo to give a yellow solid identified as N-(2-nitrobenzenesulphenyl)-L-pro!ine succinimidyl ester (78.9g, 216mmol, 100%).
1C. N-(2-Nitrobenzenesulphenyl)-L-prolinamide
N-(2-Nitrobenzenesulphenyl)-L-proline succinimidyl ester (78.5g, 215mmol) was dissolved in dioxan (500ml). Ammonia (35%, 100ml) was added. The mixture was stirred at room temperature for 2 hours then poured into water (700ml). The precipitate was collected, washed with water (200ml), dried over P205 and recrystallised from ethyl acetate/pet ether 60-80 to give a yellow solid identified as N-(2-nitrobenzenesulphenyl)-L-prolinamide (49.6g, 185mmol, 86%).
1D. (2S)-1 -(2-Nitrobenzenesulphenyl)pyrrolidine-2-carbonitrile N-(2-Nitrobenzenesulphenyl)-L-prolinamide(49g, 183mmol) was dissolved in dry THF (300ml). The solution was cooled to 0°C, triethylamine (36.7g, 367mmol) was added followed by the slow addition of trifluoroacetic anhydride (77g, 367mmol). The pH was adjusted to pH9 with triethylamine. The mixture was stirred for 30min then diluted with ethyl acetate (500ml), washed with water (1 x 200ml) and brine (1 x 200ml), dried (Na2SO4) and evaporated in vacuo to give an orange oil which was purified by flash chromatography on silica gel (eluant: 80% pet ether 60-80, 20% ethyl acetate) to give a yellow solid identified as (2S)-1-(2-nitrobenzenesulphenyl)pyrrolidine-2-carbonitrile (38.9g. 150mmol, 82%).
1E. (2S)-Pyrrolidine-2-carbonitrile hydrochloride
(2S)-1-(2-nitrobenzenesulphenyl)pyrrolidine-2-carbonitrile (38.5g, 149mmol) was dissolved in diethyl ether (200ml). 4M HCl/Dioxan (150ml, 600mmol) was slowly added. The mixture was stirred for 2h at room temperature then poured into diethyl ether (1000ml). The solid was collected, washed with diethyl ether (500ml) and recrystallised from methanol/diethyl ether to give a white solid identified as (2S)-pyrrolidine-2-carbonitrile hydrochloride (18.9g, 142.5mmol, 96%).
1F. (2S)-1 -[Nα-(tert-Butyloxycarbonyl)-N°-(pyrazinyl-2-carbonyl)-L-ornithinyl]-pyrrolidine-2-carbonitrile.
Nα-((erf-Butyloxycarbonyl)-N-(pyrazinyl-2-carbonyi)-L-ornithine (2.5g, 7.4mmol) was dissolved in CH2CI2 (50ml). This solution was cooled to 0°C, (2S)-pyrrolidine-2-carbonitrile hydrochloride (1.2g, 9.1mmol) and PyBOP (4.3g, 8.23mmol) were added, and the pH adjusted to pH9 with triethylamine. The mixture was stirred for 18h at 0°C to room temperature then the solvent was removed in vacuo and the residue was taken
up in ethyl acetate (200ml). The solution was washed with 0.3M KHSO4 (2 x 50ml), sat. NaHCO3 (2 x 50ml), water (2 x 50ml) and brine (1 x 50ml), dried (Na2SO4) and evaporated in vacuo to give a yellow oil which was purified by flash chromatography on silica gel {eluant: 80% ethyl acetate, 20% pet. ether, 60-80) to give a colourless oil identified as (2S)-1 -{N-(tert-butyloxycarbonylj-Ar-(pyrazinyl-2-carbonyl)-L-ornithinyrj-pyrrolidine-2-carbonitrile (2.98g, 7.16mmol, 97%).
1G. (2S)-1-[N-(Pyrazinyl-2-carbonyl)-L-ornithinyl]pyrrolidine-2-carbonitrile trifluoroacetate
(2S)-1-[N-tert-Butyloxycarbonyl-N0)-(pyrazinyl-2-carbonyl)-L-ornithinyl]pyrrolidine-2-carbonitrile (2.8g, 6.7mmol) was dissolved in trifluoroacetic acid (5ml). The mixture was stirred for 1 hour at room temperature then the solvent was removed in vacuo to give a colourless oil identified as (2S)-1-[N)-(pyrazinyl-2-carbonyl)-L-ornithinyl]pyrrolidine-2-carbonitrile trifluoroacetate (1.5g, 3.48mmol, 52%).
1H. (2S)-1-[N-(1'-Acetoxyethoxycarbonyl)-N-{pyrazinyl-2-carbonyl)-L-ornithinyl]-pyrrolidine-2-carbonitrile
A solution of (2S)-1-[Nα-(pyrazinyl-2-carbonyl)-L-omithinyl]pyrrolidine-2-carbonitrile trifluoroacetate (200mg, 0.47mmol), a-acetoxyethyl p-nitrophenyl carbonate (140mg, 0.52 mmol; prepared according to Alexander et a/., J. Med. Chem. 31, 318, 1988) and triethylamine (60mg, 0.6mmol) in dichloromethane (25ml) was stirred at room temperature for 18 hours then evaporated in vacuo. The residue was taken up in ethyl acetate (70ml). The solution was washed with sat NaHCO3, water and brine, dried (Na2SO4) and evaporated. The residue was purified by flash chromatography on silica gel (eluant: 98% chloroform, 2%methanol) to give a white solid identified as (2S)-1-[Nα-(1'-acetoxyethoxycarbonyl)-Ar-(pyrazinyl-2-carbonyl)-L-ornithinyl]pyrrolidine-2-carbonitrile (30mg, 0.07mmol.14%).
[M+H]+ = 447.2
1H NMR (CDCI3): δ 1.41-1.48 (3H,m), 1.72-1.86 (4H,m), 2.02 (3H,d,J=7.7Hz), 2.11-2.28 (4H,m), 3.51-3.57 (2H,m), 3.68-3.69 (2H,m), 4.47-4.48 (1H,m), 4.74-4.76 (1H,m), 5.55-5.59 (1H,m), 6.75-6.78 (1H,m), 7.89-7.91 (1H,m), 8.52 (1H,d.J=1.9Hz), 8.76 (1H,d,J=2.5Hz). 9.3 (1H,d,J=1.5Hz) ppm.
EXAMPLE 2
(4R)-3-[N°-Methoxycarbonyl)-N"-{pyrazinyl-2-carbonyl)-L-lysinyl]thiazolicline-4-carbonitrile
(Formula Removed)
2A. (4R)-3-{tert-Butyloxycarbonyl)thiazoHdine-4-carboxamide
(4R)-3-(tert-Butyloxycarbonyl)thiazolidine-4-carboxylic acid (12.5g, 54.1mmol) was dissolved in CH2CI2/DMF (9:1, 150ml). To this solution at 0°C was added 1-hydroxybenzotriazole hydrate (14.6g, 108mmol) and water-soluble carbodiimide (13.0g, 65mmol). The mixture was stirred for 1 hour at 0°C then ammonia (35%, 50ml) was added. The mixture was stirred for 18h at 0°C to room temperature then the solvent was removed in vacuo and the residue was taken up in ethyl acetate (500ml). The solution was washed with 0.3M KHSO4 (2 x 100ml), sat. NaHCO3 (2 x 100ml). water (2 x 100ml) and brine (1 x 100ml), dried (Na2SO4) and evaporated in vacuo to give a yellow oil. The residue was purified by flash chromatography on silica gel (eluant: 2% methanol, 98% chloroform) to give a colourless oil identified as (4R)-3-(tert-butyloxycarbonyl)thiazolidine-4-carboxamide (8.9g, 38.4mmol,71%).
2B. (4R)-Thiazolidine-4-carboxarnide hydrochloride
(4S)-3-(tert-Butyloxycarbonyl)thiazolidine-4-carboxamide (8.6g, 37.1mmol) was dissolved in 4M HCI/dioxan (50ml). The mixture was stirred for 1 hour at room temperature then the solvent was evaporated in vacuo to give a white solid identified as (4R)-thiazolidine-4-carboxamide hydrochloride (6.2g, 36.8mmol, 99%).
2C. (4R)-3-[Na-(tert-Butyloxycarbonyl)-N0,-(9-fluorenylmethyloxycarbonyl)-L-lysinyl]thiazolidine-4-carboxamide
Na-(tert-Butyloxycarbonyl)-Ar-(9-fluorenylmethyloxycarbonyl)-L-lysine (5g, 10.7mmol) was dissolved in CH2CI2 (100ml). This solution was cooled to 0°C, (4R)-thiazolidine-4-carboxamide hydrochloride (1.78g, 11.7mmol) and PyBOP (6.7g, 12.8mmol) were
added, and the pH was adjusted to pH9 with triethylamine. The mixture was stirred for 18h at 0°C to room temperature then the solvent was removed in vacuo and the residue was taken up in ethyl acetate (200ml). The solution was washed with 0.3M KHSO4 (2 x 50ml), sat. NaHCO3 (2 x 50ml), water (2 x 50ml) and brine (1 x 50ml), dried (Na2SO4) and evaporated in vacuo to give a yellow oil. The residue was purified by flash chromatography on silica gel (eluant: 2% methanol, 98% chloroform) to give a colourless oil identified as (4/^)-3-[Na-(tert-butyloxycarbonyl)-Nu-(9-fluorenylmethyloxy-carbonyl)-L-lysinyl]thiazolidine-4-carboxamide (2.81 g, 4.8mmol, 44%).
2D. (4R)-3-[Na-(tert-Butyloxycarbonyl)-Nw-(9-fIuorenylmethyloxycarbonyl)-L-lysinyl]thiazolidine-4-carbonitriie
(4R)-3-[/v°-(fe/t-ButyloxycarbonyJ)-Na,-(9-fluorenylmethyloxycarbonyl)-L-lysinyl]-
thiazolidine-4-carboxamide (2.7g, 4.7mmol) was dissolved in dry THF (100ml). The
solution was cooled to 0°C and triethylamine (1.0g, 10mmol) was added followed by
the slow addition of trifluoroacetic anhydride (2.0g, 9.5mmol). The pH was adjusted to
pH9 with triethylamine. The mixture was stirred for 30min then diluted with ethyl
acetate (100ml), washed with water (1 x 50ml) and brine (1 x 50ml), dried (Na2SO4)
and evaporated in vacuo. The residue was purified by flash chromatography on silica
gel (eluant: 60% pet ether 60-80, 40% ethyl acetate) to give a colourless oil identified
as (4R)-3-[/\r-(tert-buryloxycarbonyl)-N<0-(9-fluorenylmethyloxycarbonyl)-L-Iysinyl]-
thiazolidine-4-carbonitrile (2.14g, 3.81 mmol, 82%).
2E. (4R)-3-[Na-(tert-Butyloxycarbonyl)-L-lysinyl]thiazolidine-4-carbonitrile
(4R)-3-[Na-(tert-Butyloxycarbonyl)-N0,-(9-fluorenylmethyloxycarbonyl)-L-lysinyl]-thiazolidine-4-carbonitrile (1.9g, 3.4mmol) was dissolved in THF (40ml). Diethylamine (10ml) was added. The mixture was stirred for 2h at room temperature then the solvent was removed in vacuo. The residue was purified by flash chromatography on silica gel (eluant: 90% chloroform, 7% methanol, 3% triethylamine) to give a colourless oil identified as (4f?)-3-[Na-(tert-butyloxycarbonyl)-L-lysinyl]thiazolidine-4-carbonitriie (863mg, 2.5mmol, 75%).
2F. (4R)-3-[Na-(tert-Butyloxycarbonyl)-N0>-(pyrazinyl-2-carbonyl)-L-lysinyl]-thiazolidine-4-carbonitrile
(4f?)-3-[Na-(tert-Butyloxycarbonyl)-L-lysinyl]thiazolidine-4-carbonitrile (100mg,
0.29mmol) was dissolved in CH2CI2 (20ml). To this solution at 0°C were added 2-
pyrazinecarboxylic acid (43mg, 0.35mmol) and PyBOP (170mg, 0.33mmol) and the pH was adjusted to pH9 with triethylamine. The mixture was stirred for 18 h at 0°C to room temperature then the solvent was removed in vacuo and the residue was taken up in ethyl acetate (70ml). The solution was washed with 0.3M KHSO4 (2 x 20ml), sat. NaHCO3 (2 x 20ml), water (2 x 20ml) and brine (1 x 20ml), dried (Na2SO4) and evaporated in vacuo. The residue was purified by flash chromatography on silica gel (eluant: 2% methanol, 98% chloroform) to give a colourless oil identified as (4R)-3-[N°-(tert-butyloxycarbonyl)-N-(pyrazinyi-2-carbonyl)-L-lysinyl]thiazolidine-4-carbonitrile (112mg,0.25mmol, 86%).
2G. (4R)-3-[( Nα-Methoxycarbonyl)- N-(pyrazinyl-2-carbonyl)-L-lysinyl]-thiazolidine-4-carbonitrile
{4R)-3-[Nα-(tert-Butyloxycarbonyl)-N-(pyrazinyl-2-carbonyl)-L-lysinyl]thiazolidine-4-carbonitrile (160mg, 0.36mmol) was dissolved in 4M HCI/dioxan (30ml). The mixture was stirred for 1 hour at room temperature then the solvent was removed in vacuo. The residue was dissolved in dichloromethane (25 ml). Methyl chloroformate (50mg, 0.53mmol) and triethylamine (60mg, 0.6 mmol) were added and the solution was stirred at room temperature for 18 hours then solution was evaporated in vacuo. The residue was taken up in ethyl acetate (70ml). The solution was washed with sat NaHCO3, water and brine, dried (Na2SO4) and evaporated. The residue was purified by flash chromatography on silica gel (eluant: 90% ethyl acetate: 10% pet. ether 60-80) to give a white solid identified as (4R)-3-[(Nα-methoxycarbonyl)-N-(pyrazinyl-2-carbonyl)-l-lysinyl]thiazolidine-4-carbonitrile (52mg, 0.13mmol, 35%).
[M+H]+ = 407.1
1H NMR (CDCI3): δ 1.33-1.48 (4H,m), 1.63-1.82 (2H,m), 3.21-3.27 (2H,m), 3.45-3.60 (2H,m), 3.63 (3H,s), 4.44-4.46 (1H,m), 4.63 (1H,d,J=8.4Hz), 4.86 (1H,d,J=8.5Hz), 5.23-5.27 (1H,m), 5.53 (1H,d,J=8.2Hz), 7.85-7.87 (1H,m), 8.50-8.51 (1H,m), 8.73 (1H,d,J=2.5Hz), 9.38 (1H,d,J = 1,3Hz) ppm.
EXAMPLE 3
(4R)-3-[Nα-(1'-Acetoxyethoxycarbonyl)-Ar-(3-cyanobenzenesulphonyl)-L-
ornithinyl]thiazoiidine-4-carbonitrile
(Formula Removed)
3A. (4R)-3-[Na-{tert-Butyloxycarbonyl)-Na-(9-fluoreny!methyloxycarbonyl)-L-omithinyl]thiazolidine-4-carboxamide
N°-(tert-Butyloxycarbonyl)-N0,-(9-fluorenylmethyloxycarbonyl)-L-ornithine (2.8g,
6.2mmol) was dissolved in CH2CI2 /DMF (9:1, 100ml). This solution was cooled to 0°C, (4R)-thiazolidine-4-carboxamide hydrochloride (1.78g, 11.7mmol), 1-hydroxybenzotriazole hydrate (1.1g, 8.1mmol) and water-soluble carbodiimide (1.5g, 7.5mmol) were added, and the pH was adjusted to pH8 with N-methylmorpholine. The mixture was stirred for 18h at 0°C to room temperature then the solvent was removed in vacuo and the residue was taken up in ethyl acetate (200ml). The solution was washed with 0.3M KHSO< (2 x 50mi), sat. NaHCO3 (2 x 50ml), water (2 x 50ml) and brine (1 x 50ml), dried (Na2SO4) and evaporated in vacuo to give a yellow oil. The residue was purified by flash chromatography on silica gel (eluant: 85% ethyl acetate, 15% pet. ether 60-80) to give a colourless oil identified as (4R)-3-[N°-(tert-butyloxycarbonyl)-N"-(9-fluorenylmethyloxycarbonyl)-L-ornithinyl]thiazolidine-4-carboxamide (2.26g, 3.9mmol, 66%).
3B. (4R)-3-[Na-(tert-Butyloxycarbonyl)-AT-(9-fluorenylmethyloxycarbonyl)-L-ornithinyl]thiazolidine-4-carbonitrile
(4R)-3-[Na-(tert-Butyloxycarbonyl)-NM-(9-fluorenylmethyloxycarbonyl)-L-ornithinyl]-thiazolidine-4-carboxamide (2.1 g, 3.7mmol) was dissolved in dry THF (100ml). The solution was cooled to 0°C, triethylamine (740mg, 7.4mmol) was added followed by the slow addition of trifluoroacetic anhydride (1.65g, 7.9mmol). The pH was adjusted to pH9 with triethylamine. The mixture was stirred for 30min then diluted with ethyl
acetate (100ml), washed with water (1 x 50ml) and brine (1 x 50ml), dried (Na2SO4) and evaporated in vacuo. The residue was purified by flash chromatography on silica gel (eluant: 45% pet ether 60-80, 55% ethyl acetate) to give a colourless oil identified as (4R)-3-{NCI-(tert-butyloxycarbonyl)-N0,-(9-fiuorenylmethyloxycarbonyl)-L-omithinyl]-thiazolidine-4-carbonitrite (1.73g, 3.14mmol, 85%).
3C. (4R)-3-[//I-(tert-Butyloxycarbonyl)-L-ornithinyllthiazolidine-4-cart)onitrile
(4R)-3-[Na-(tert-Butyloxycarbonyl)-Nu-(9-fluorenylmethyloxycarbonyl)-L-ornithinyl]-thiazolidine-4-carbonitrile (1.6g, 2.9mmol) was dissolved in THF (40ml). Diethylamine (10ml) was added. The mixture was stirred for 2h at room temperature then the solvent was removed in vacuo. The residue was purified by flash chromatography on silica gel (eluant: 90% chloroform, 7% methanol, 3% triethylamine) to give a colourless oil identified as (4R)-3-[Na-(tert-butyloxycarbonyl)-L-omithinyl]thiazolidine-4-carbonitrile (902mg, 2.75mmol, 95%).
3D. (4R)-3-[Wa-(tert-Butyloxycarbonyl)-ATD-(3-cyanobenzenesuIphonyl)-L-ornithinyl]thiazolidine-4-carbonitrile
(4/:?)-3-[N0-(feft-Butyloxycarbonyl)-L-ornithinyl]thiazolidine-4-carbonitrile (207mg,
0.63mmol) was dissolved in CH2CI2 (25ml). To this solution at 0°C was added 3-cyanobenzenesulphonyl chloride (135mg, 0.67mmol) and the pH was adjusted to pH9 with triethylamine. The mixture was stirred for 18 h at 0°C to room temperature then the solvent was removed in vacuo and the residue was taken up in ethyl acetate (70ml). The solution was washed with 0.3M KHSO4 (2 x 20ml), sat. NaHCO3 (2 x 20ml), water (2 x 20ml) and brine (1 x 20ml), dried (Na2SO4) and evaporated in vacuo. The residue was purified by flash chromatography on silica gel (eluant: 45% ethyl acetate: 55% pet. ether 60-80°C) to give a colourless oil identified as (4R)-3-[Na-(tert-butyloxycarbonyl)-N°-(3-cyanobenzenesulphonyl)-L-ornithinyl]thiazolidine-4-carbonitrile (162mg, 0.33mmol, 52%).
3E. (4R)-3-[Na-(1*-Acetoxyethoxycarbonyl)-W0,-(3-cyanobenzenesulphonyl)-L-ornithinyl]thiazolidine-4-carbonitrile
(4R)-3-[Na-(tert-Butyloxycarbonyl)-Nm-(3-cyanobenzenesulphonyl)-L-ornithinyl]-thiazolidine-4-carbonitrile (142mg, 0.29mmol) was dissolved in trifluoroacetic acid (5ml). The mixture was stirred for 1 hour at room temperature then the solvent was
removed in vacuo. The residue was dissolved in dichloromethane (25ml) and -methyl-L-glutamyl]pyrrolidine-2-carbonitrile (290mg, 0.86mmol, 22%).
4B. (2S)-1-[N-(tert-Butyloxycarbonyl)-L-glutamyl]pyrrolidine-2-carbonitrile
(2S)-1-[W-(tert-Butyloxycarbonyl)-Ou-methyl-L-glutamyl]pyrrolidine-2-carbonitrile
(250mg, 0.74mmol) was dissolved in dioxan (5ml). 1M Lithium hydroxide (1.1ml,
1.1 mmol) was added. The mixture was stirred for 1 hour at room temperature then the
solvent was removed in vacuo and the residue was taken up in ethyl acetate (70ml).
The solution was washed with 1M KHSO4 (2 x 20ml), water (2 x 20ml) and brine (1 x
20ml), dried (Na2SO4) and evaporated in vacuo to give a colourless oil identified as
(2S)-1-[N-(tert-butyloxycarbonyl)-L-glutamyf]pyrrolidine-2-carbonitrile (200mg,
0.61 mmol, 83%).
4C. (2S,2'S)-1-[2'-(tert-Butyloxycarbonylamino)-5'-oxo-5'-(tetrahydroisoquinolin-2-yl)pentanoyl]pyrrolidine-2-carbonitrile
(2S)-1-[N-(tert-Butyloxycarbonyl)-L-glutamyl]pyrrolidine-2-carbonitrile (200mg,
0.61 mmol) was dissolved in CH2CI2/DMF (9:1, 20ml). To this solution at 0°C were added 1-hydroxybenzotriazole hydrate (98mg, 0.73mmol), water-soluble carbodiimide (140mg, 0.73mmol), tetrahydroisoquinoline (109mg, 0.82mmol) and triethylamine(150mg, 1.5mmol). The mixture was stirred for 18h at 0°C to room temperature then the solvent was removed in vacuo and the residue was taken up in ethyl acetate (70ml). The solution was washed with 0.3M KHSO4 (2 x 20ml), sat. NaHCOj (2 x 20ml), water (2 x 20ml) and brine (1 x 20ml), dried (Na2SO4) and evaporated in vacuo to give a yellow oil. The residue was purified by flash chromatography on silica gel (eluant: 5% methanol, 97% chloroform) to give a colourless oil identified as ,(2S,2'S)-1-[2'-(tert-butyloxycarbonylamino)-5'-oxo-5'-(tetrahydroisoquinolin-2-yl)pentanoyl]pyrrolidine-2-carbonitrile (149mg, 0.34mmol, 56%).
4D. (2S,2'S)-1-[2'-(1"-Acetoxyethoxycarbonylamino)-5'-oxo-5'-{tetrahydro-isoquinolin-2-yl)pentanoyl]pyrrolidine-2-carbonitrile
(2S,2'S)-1-[2'-(fe/t-butyloxycarbonylamino)-5'-oxo-5'-(tetrahydroisoquinolin-2-yl)-pentanoyl]pyrrolidine-2-carbonitrile (149mg, 0.34mmol) was dissolved in trifluoroacetic acid (20ml). The mixture was stirred for 1 hour at room temperature then the solvent was removed in vacuo. The residue was dissolved in dichloromethane (25ml) and a-acetoxyethyl p-nitrophenyl carbonate (100mg, 0.37 mmol; prepared according to Alexander et a/., J. Med. Chem. 31, 318, 1988) and triethylamine (40mg, 0.4mmol) were added. The reaction was stirred at room temperature for 18 hours then evaporated in vacuo and the residue was taken up in ethyl acetate (70ml). The solution was washed with sat NaHCO3, water and brine, dried (Na2SO4) and evaporated. The residue was purified by flash chromatography on silica gel (eluant: 90% ethyl acetate, 10% pet. ether 60-80°C) to give a white solid identified as (2S,2'S)-1-[2'-(1"-Acetoxyethoxycarbonylamino)-5'-oxo-5'-(tetrahydroisoquinolin-2-yl)pentanoyl]pyrrolidine-2-carbonitrile (58mg, 0.12mmol, 36%).
[M+H]+ = 471.2
1H NMR (CDCI3): 6 1.40-1.44 (3H,m), 2.00-2.07 (3H,m), 2.13-2.40 (9H,m), 2.82-2.91 (2H,m), 3.63-3.70 (2H,m), 3.96-4.18 (1H,m), 4.57-4.61 (2H.m), 4.72-4.75 (2H,m), 5.78-5.80 (1H.m), 6.69-6.75 (1H.m), 7.10-7.25 (4H,m) ppm.
EXAMPLE 5
(2S)-1-[W°-(4'-Oxopent-2'-en-2'-y|)-Ar-(quinoxalinyl-2-carbonyl)-L-ornithinyl]-
pyrrolidine-2-carbonitriIe
(Formula Removed)
5A. 1-[Na-(tert-Butyloxycarbonyl)-N0)-{9-fluorenylmethyloxycarbonyl)-L-ornithinyl]-L-prolineamrde
Na-(tert-Butyloxycarbonyl)-N,-(9-fluorenylmethyloxycarbonyl)-L-ornithine (5g,
H.Ommol) was dissolved in CH2CI2 (40ml). This solution was cooled to 0°C, L-
prolineamide (1.4g, 12.2 mmol)and PyBOP (6.3g, 12.1mmol) were added, and the pH
was adjusted to pH9 with triethylamine. The mixture was stirred for 18h at 0°C to room
temperature then the solvent was removed in vacuo and the residue was taken up in
chloroform (200ml). The solution was washed with 0.3M KHSO4 (2 x 50ml), sat.
NaHCO3 (2 x 50ml), water (2 x 50ml) and brine (1 x 50ml), dried (Na2SO4) and
evaporated in vacuo to give a yellow oil. The residue was purified by flash
chromatography on silica gel (eluant: 98% chloroform, 2% methanol) to give a
colourless oil identified as 3-[Na-(tert-butyloxycarbonyl)-N'-(9-
fluorenylmethyloxycarbonyl)-L-omithinyf]-L-prolineamide (4.2g, 7.6mmol, 69%).
5B. (2S)-1-[Na-((ert-Butyloxycarbonyl)-N°'-(9-fluorenylmethyloxycarbonyl)-L-omithinyl]pyrrolidine-2-carbonitrile
N-[Ar-(tert-Butyloxycarbonyl)-Ar-(9-fluorenylmethyloxycarbonyl)-L-omithinyl]-L-proline-amide (4.1 g, 7.4mmol) was dissolved in dry THF (100ml). The solution was cooled to 0°C and triethylamine (820mg, 8.2mmol) was added followed by the slow addition of trifluoroacetic anhydride (1.7g, 8.1mmol). The pH was adjusted to pH9 with triethylamine. The mixture was stirred for 30min then diluted with ethyl acetate (100ml), washed with water (1 x 50ml) and brine (1 x 50ml), dried (Na2SO4) and evaporated in vacuo. The residue was purified by flash chromatography on silica gel (eluant: 20% ethyl acetate, 80% pet. ether 60-80) to give a colourless oil identified as (2S)-1-[Na-(tert-butyloxycarbonyl)-Na>-(9-fluorenylmethyloxycarbonyl)-L-ornithinyl]pyrrolidine-2-carbonitrile (3.5g, 6.5mmol, 87%).
5C. (2S)-1-[Na-(tert-Butyloxycarbonyl)-L-ornithinyl]pyrrolidine-2-carbonitrile
(2S)-1-[Na-(tert-Butyloxycarbonyl)-N0,-(9-fluorenylmethyloxycarbonyl)-L-ornithinyl]-
pyrrolidine-2-carbonitrile (3.4g, 6.4mmol) was dissolved in THF (40ml). Diethylamine
(10ml) was added. The mixture was stirred for 2h at room temperature then the
solvent was removed in vacuo. The residue was purified by flash chromatography on
silica gel (eluant: 90% chloroform, 7% methanol, 3% triethylamine) to give a colourless
oil identified as (2S)-1-[Na-(tert-butyloxycarbonyl)-L-ornithinyl]pyrrolidine-2-carbonitrile
(1.48g, 4.77mmol, 75%).
5D. (ZS^I-IA^-ltert-ButyloxycarbonylJ-Ar^quinoxalinyl^-carbonylJ-L-ornithinyl]-pyrrolidine-2-carbonitrile
(2S)-1-[Na-(teft-Butyloxycarbonyl)-L-ornithinyl]pyrrolidine-2-carbonitrile (300mg,
0.97mmol) was dissolved in CH2CI2 (25ml). To this solution at 0°C was added 2-quinoxaloyl chloride (200mg, 1.04mmol) and the pH was adjusted to pH9 with triethylamine. The mixture was stirred for 18 h at 0°C to room temperature then the solvent was removed in vacuo and the residue was taken up in ethyl acetate (70ml). The solution was washed with 0.3M KHSO4 (2 x 20ml), sat. NaHCO3 (2 x 20ml), water (2 x 20ml) and brine (1 x 20ml), dried (Na2SO4) and evaporated in vacuo. The residue was purified by flash chromatography on silica gel (eluant: 60% ethyl acetate, 40% pet. ether 60-80) to give a colourless oil identified as (2S)-1-[N0-(tert-butyloxycarbonyl)-N0>-(quinoxalinyl-2-carbonyl)-L-omithinyl]pyrrolidine-2-carbonitrile (31 Omg, 0.67mmol, 69%).
5E. (2S)-1-[Wa-(4'-Oxopent-2'-en-2'-yl)-AT-(quinoxalinyl-2-carbonyl)-L-ornithinyl3-pyrrolidine-2-carbonitriie
(2S)-1-[Na-(tert-Butyloxycarbonyl)-N<,>-(quinoxalinyl-2-carbonyl)-L-ornithinyl]pyrrolidine-2-carbonitriie (160mg, 0.34mmol) was dissolved in trifluoroacetic acid (20 ml). The mixture was stirred for one hour at room temperature then the solvent was removed in vacuo. The residue was dissolved in dichloromethane (25ml) and 2,4-pentanedione (48mg, 0.48mmol) and triethylamine (100mg, LOmmol) were added. The reaction was stirred at room temperature for 18 hours then evaporated in vacuo. The residue taken up in ethyl acetate (70ml). The solution was washed with sat NaHCO3, water and brine, dried (Na2SO4) and evaporated. The residue was purified by flash chromatography on silica gel (eluant: 98% chloroform, 2% methanol) to give a white solid identified as (2S)-1-[Na-(4'-oxopent-2'-en-2'-yl)-/\T-(quinoxalinyl-2-carbonyl)-L-ornithinyl]pyrrolidine-2-carbonitrile (87mg, 0.19mmol, 57%).
[M+H]* = 449.2
1H NMR (CDCI3): δ 1.89-2.02 (10H.2 x s+m), 2.13-2.24 (4H,m), 3.57-3.62 (5H,m), 4.3-4.6 (1H,m), 4.70-4.81 (1H,m), 5.02 (1H,s), 7.83-7.88 (2H,m), 8.10-8.19 (3H,m), 9.62 (1H,s). 11.0-11.2 (1H,m)ppm.
EXAMPLE 6
(2S)-1-[N-Acetoxymethoxycarbonyl-S-{3-picolylcarbamoylmethyl)-L-cysteinyl]-
pyrrolidine-2-carbonitrile
(Formula Removed)
6A. S-{Benzyloxycarbonylmethyl)-W-(tert-butyloxycarbonyl)-L-cysteine
N-(tert-Butyloxycarbonyl)-L-cysteine (3.5g, 15.8mmol), benzyl 2-bromoacetate (3.7g,16.1mmol) and triethylamine (1.8g, 18.0mmol) were dissolved in THF (100ml). The mixture was stirred for 18 hours at room temperature then diluted with ethyl acetate (100ml), washed with 0.3M KHSO4, sat NaHCO3, water and brine, dried (Na2SO4) and evaporated in vacuo. The residue was purified by flash chromatography on silica gel (eluant: 95% chloroform, 4% methanol, 1% acetic acid) to give a colourless oil identified as S-(benzyloxycarbonylmethyl)-N-(tert-butyloxycarbonyl)-L-cysteine (5.2g, 14.1mmol, 89%).
6B. (2S)-1-[S-(BenzyIoxycarbonylmethyl)-W-(tert-butyloxycarbonyl)-L-cysteinyl]-pyrrolidine-2-carbonitriIe
S-(BenzyloxycarbonylmethyI)-/v"-(tert-butyloxycarbonyl)-L-cysteine (5.1 Og, 13.8mmol) was dissolved in CH2CI2 (200ml). This solution was cooled to 0°C, (2S)-pyrrolidine-2-carbonitrile hydrochloride (2.1g, 15.8mmol) and PyBOP (8.0g, 15.3mmol) were added, and the pH adjusted to pH9 with triethylamine. The mixture was stirred for 18h at 0°C to room temperature then the solvent was removed in vacuo and the residue was taken up in ethyl acetate (150ml). The solution was washed with 0.3M KHSO4 (1 x 50ml), sat. NaHCO3 (1 x 50ml), water (1 x 50ml) and brine (1 x 50ml), dried (Na2SO4) and evaporated in vacuo to give a yellow oil which was purified by flash chromatography on silica gel (eluant: 40% ethyl acetate, 60% pet. ether 60-80) to give a colourless oil
identified as (2S)-1-[S-(benzyloxycarbonylmelhyl)-N-(tert-butyloxycarbonyl)-L-cysteinyl]pyrrolidine-2-carbonitrile (5.82g, 13.0mmol, 94%).
6C. (2S)-1-[W-(tert-Butyloxycarbonyl)-S-{carboxymethyl)-L-cysteinyl]pyrrolidine-2-carbonitrile
(2S)-1-[S-(Benzyloxycarbonylmethy!)-N-(tert-butyloxycarbonyl)-L-cysteinyi]pyrrolidine-2-carbonitrile (1.31g, 2.9mmol) was dissolved in THF(100ml). 1M Lithium hydroxide (3.5ml, 3.5mmol) was added. The mixture was stirred for 3 hours at room temperature then with ethyl acetate (100ml), washed with 1M citric acid, water and brine, dried (Na2SO4) and evaporated in vacuo to give a colourless oil which was purified by flash chromatography on silica gel (eluant: 97% chloroform, 2% methanol, 1% acetic acid) to give a colourless oil identified as (2S)-1-[N-(tert-butyloxycarbonyl)-S-(carboxymethyl)-L-cysteinyl]pyrrolidine-2-carbonitrile (860mg, 2.4mmol, 82%).
6D. (2S)-1-[W-(tert-Butyloxycarbonyl)-S-(3-picolylcarbamoylmethyl))-L-cysteinyl]-pyrrolidine-2-carbonitrHe
(2S)-1-[N-(/e/t-Butyloxycarbonyi)-S-(carboxymethyl)-L-cysteinyl]pyrrolidine-2-carbonitrile (150mg, 0.42mmol) was dissolved in CH2CI2 (20ml). The solution was cooled to 0°C, 3-(aminomethyl)pyridine (53mg, 0.5mmol) and PyBOP (270mg, 0.52mmol) were added, and the pH was adjusted to pH9 with triethylamine. The mixture was stirred for 18h at 0°C to room temperature then the solvent was removed in vacuo and the residue was dissolved in ethyl acetate (70ml). The solution was washed with 0.3M KHSO4 (1 x 20ml), sat. NaHCO3 (1 x 20ml), water (1 x 20ml) and brine (1 x 20ml), dried (Na2SO<) and evaporated in vacuo to give a yellow oil which was purified by flash chromatography on silica gel (eluant: 96% chloroform, 4% methanol) to give a colourless oil identified as (2S)-1-[N-(tert-buty!oxycarbonyl)-S-(3-picolylcarbamoylmethyl))-L-cysteinyl]pyrrolidine-2-carbonitrile (170mg, 0.38mmol, 91%).
6E. (2S)-1-[N°-Acetoxymethoxycarbonyl-S-(3-picolylcarbamoylmethyl)-L-cysteinyl]pyrrolidine-2-carbonitrile
(2S)-1-[N-(te/t-Butyloxycarbonyl)-S-(3-picolylcarbamoylmethyl)-L-cysteinyl]pyrrolidine-2-carbonitrile (130mg, 0.29mmol) was dissolved in trifluoroacetic acid (20ml). The solution was stirred for 1 hour at room temperature then the solvent was removed in vacuo. The residue was dissolved in dichloromethane (25mi) and acetoxymethyl p-
nitrophenyl carbonate (80mg, 0.31 mmol; prepared according to Alexander et a/., J. Med. Chem. 31, 318, 1988) and triethylamine (40mg, 0.4mmol) were added. The solution was stirred at room temperature for 18 hours then evaporated in vacuo and the residue was taken up in ethyl acetate (70ml). The solution was washed with sat NaHCOj, water and brine, dried (Na2SO4) and evaporated. The residue was purified by flash chromatography on silica gel (eluant: 90% ethyl acetate, 10% pet. ether 60-80) to give a white solid identified as (2S)-1-[Na-acetoxymethoxycarbonyl-S-(3-picolylcarbamoylmethyl)-L-cysteinyl]pyrrolidine-2-carbonitrile (33mg, 0.071 mmol, 24%).
[M+H]+ = 464.0
1H NMR (CDCI3): δ 2.08 (3H,s), 2.13-2.29 (4H,m), 2.89 (2H,d,J=6.9Hz), 3.20-3.29
(2H,m), 3.61-3.74 (2H,m), 4.46 (2H,d,J=5.9Hz), 4.60-4.71 (2H,m), 5.68 (2H,s), 6.12
(1H,d,J=8.6Hz), 7.16-7.27 (2H,m), 7.66 (1H,d,J=8.1Hz), 8.50 (1H,d,J=4.7Hz), 8.56
(1H,s)ppm.
EXAMPLE 7
3.[Na.{i'-Acetoxyethoxycarbonyl)-Ar*-{5I6-dichloronicotinoyl)-L-ornithinyl]-
thiazolidine
(Formula Removed)
7A. S-lA^-ttert-ButyloxycarbonyO-N^-tS-fluorenylmethyloxycarbonylJ-L-ornithinyl]thiazolidine
Na-(tert-Butyloxycarbonyl)-N<,'-(9-fluorenylmethyloxycarbonyl)-L-ornithine (2.73g,
6mmol) was dissolved in CH2CI2/DMF (9:1, 100ml). To this solution at 0°C were added 1-hydroxybenzotriazole hydrate (1.53g, 10mmol), water-soluble carbodiimide (1.34g, 7mmol), thiazolidine (1.28g, 18mmol) and triethylamine (80mg, 8mmol). The mixture was stirred for 18h at 0°C to room temperature then the solvent was removed
in vacuo and the residue was taken up in ethyl acetate (100ml). The solution was washed with 0.3M KHSO4 (2 x 25ml), sat. NaHCO3 (2 x 25ml), water (2 x 25ml) and brine (1 x 25ml), dried (Na2SO4) and evaporated in vacuo. The residue was purified by flash chromatography on silica gel (eluant: 75% ethyl acetate, 25% pet. ether 60-80) to give a white solid identified as 3-[Na-(fen,-butyloxycarbonyl)-N0,-(9-fluorenylmethyloxycarbonyl)-L-ornithinyl]thiazolidine (2.55g, 4.85mmol, 81%).
7B. 3-[W-(tert-Butyloxycarbonyl)-L-ornithinyl]thiazolidine
3-[Na-(fe/t-Butyloxycarbonyl)-AT-(9-fluorenylmethyloxycarbonyl)-L-ornithinyl]thiazolidine (1.15g, 2.13mmol) was dissolved in acetonitrile (20ml). Diethylamine (5ml) was added. The mixture was stirred for 90min at room temperature then the solvent was removed in vacuo and the residue was purified by flash chromatography on silica gel (eluant: 90% chloroform, 7% methanol, 3% triethylamine) to give a pale yellow oil identified as 3-[N°-(tert-butyloxycarbonyl)-L-ornithinyl]thiazolidine (530mg, 1.67mmol, 78%).
7C. 3-[Wa-(tert-Butyloxycarbonyl)-NtD-(5,6-dichloronicotinoyl)-L-ornithinyl]-thiazolidine
3-[N°-(tert-Butyloxycarbonyl)-L-ornithinyl]thiazolidine (600mg, 1.96mmol) was dissolved in CH2CI2/DMF (9:1, 50ml). To this solution at 0°C were added 1-hydroxybenzotriazole hydrate (360mg, 2.36mmol), water-soluble carbodiimide (472mg, 2.36mmol), 5,6-dichloronicotinic acid (416mg, 2.16mmol) and triethylamine (360mg, 3.6mmol). The mixture was stirred for 18h at 0°C to room temperature then the solvent was removed in vacuo and the residue was taken up in ethyl acetate (70ml). The solution was washed with 0.3M KHSO4 (2 x 20ml), sat. NaHCOj (2 x 20ml), water (2 x 20ml) and brine (1 x 20ml), dried (Na2SO4) and evaporated in vacuo. The residue was purified by flash chromatography on silica gel (eluant: 2% methanol, 98% chloroform) to give a sticky white solid identified as 3-[Na-(tert-butyloxycarbonyl)-Na,-(5,6-dichloronicotinoyl)-L-ornithinyl]thiazolidine(512mg, 1.08mmol, 56%).
7D. S-tA^-tl'-AcetoxyethoxycarbonyO-AT-tS.S-dichloronicotinoyO-L-ornithinyl]-thiazolidine
3-[Na-(rert-Butyloxycarbonyl)-AT-(5,6-dichloronicotinoyl)-L-omithinyl]thiazolidine
(128mg, 0.27mmo!) was dissolved in 4M HCl/dioxan (20ml). The mixture was stirred
for 1 hour at room temperature then the solvent was removed in vacuo. The residue
was dissolved in dichloromethane (25ml) and a-acetoxyethyl p-nitrophenyl carbonate (83mg, 0.3mmol; prepared according to Alexander et a/., J. Med. Chem. 31, 318,1988) and triethylamine (40mg, 0.4mmol) were added. The solution was stirred at room temperature for 18 hours then evaporated in vacuo. The residue was taken up in ethyl acetate (70ml). The solution was washed with sat NaHCO3, water and brine, dried (Na2SO4) and evaporated. The residue was purified by flash chromatography on silica gel (eluant: 75% ethyl acetate, 25% pet. ether 60-80) to give a white solid identified as 3-[Na-(1'-acetoxyethoxycarbonyl)-Ar-(5,6-dichloronicotinoyl)-L-omithinyl]thiazolidine (67mg,0.13mmol, 47%).
[M+H]* = 509.0
1H NMR (CDCIj): δ 1.44-1.46 (3H, m), 1.63-1.99 (3H,br m), 1.99-2.04 (4H,m), 2.98-3.06 (2H,m), 3.46-3.48 (2H,m). 3.50-3.80 (2H,m), 4.47-4.56 (3H,m), 5.81-5.91 (1H,m), 6.74-6.75 (1H,m), 7.24-7.33 (1H,m), 8.24-8.25 (1H,m), 8.69-8.71 (1H,m) ppm.
EXAMPLE 8 3-tNa-Methoxycarbonyl-AT-(6-trif1uoromethylnicotinoyl)-L-ornithinyl]thiazolidine
(Formula Removed)
8A. S-tW'^tert-ButyloxycarbonyO-W^e-trifluoromethylnicotinoylJ-L-ornithinyl]-thiazolidine
3-[N°-(tert-Butyloxycarbonyl)-L-ornithinyl]thiazolidine (150mg, 0.49mmol) was dissolved in CH2CI2/DMF (9:1, 20ml). To this solution at 0°C were added 1-hydroxybenzotriazole hydrate (100mg, 0.74mmol), water-soluble carbodiimide (118mg, 0.59mmol), 6-trifluoromethylnicotinic acid (104mg, 0.54mmol) and triethylamine (100mg, LOmmol). The mixture was stirred for 18h at 0°C to room temperature then the solvent was removed in vacuo and the residue was taken up in ethyl acetate (70ml). The solution was washed with 0.3M KHSO4 (2 x 20ml), sat. NaHCO3 (2 x 20ml), water (2 x 20ml) and brine (1 x 20ml), dried (Na2SO4) and evaporated in vacuo. The residue was
purified by flash chromatography on silica gel (eluant: 6% methanol, 94% chloroform) to give a sticky white solid identified as 3-[Na-(tert-butyloxycarbonyl)-N,-(6-trifluoromethylnicotinoyl)-L-ornithinyl]thiazolidine (76mg, 0.16mmol, 32%).
8B. 3-[W-Methoxycarbonyl-N"-{6-trifluoromethylnicotinoyl)-L-ornithinyl]-thiazolidine
3-[Na-(tert-Butyloxycarbonyl)-N"-(6-trifluoromethylnicotinoyl)-L-ornithinyl]thiazolidine
(76mg, 0.16mmol) was dissolved in 4M HCI/dioxan (20ml). The mixture was stirred for
1 hour at room temperature then the solvent was removed in vacuo. The residue was
dissolved in dichloromethane (25ml) and methyl chloroformate (17mg, 0.18 mmol) and
triethylamine (20mg, 0.2mmol) were added. The solution was stirred at room
temperature for 18 hours then evaporated in vacuo. The residue was taken up in ethyl
acetate (70ml). The solution was washed with sat NaHCO3l water and brine, dried
(Na2SO4) and evaporated. The residue was purified by flash chromatography on silica
gel (eluant: 3% methanol, 97% chloroform) to give a white solid identified as 3-[Na-
methoxycarbonyl-AT-(6-trifluoromethylnicotinoyl)-L-omithinyl]thiazolidine (66mg,
0.15mmol, 96%).
[M+H]+ = 435.1
'H NMR (CDCIj): δ 1.36-1.79 (4H,m), 2.98-3.11 (2H,m), 3.48-3.60 (2H,m), 3.64 (3H,s), 3.72^.10 (3H,m), 4.57-4.60 (2H,m), 5.63-5.76 (1H,m), 6.55 (1H,br m), 7.54-7.55(1 H,m), 8.77-8.79 (2H,m) ppm.
EXAMPLE 9 S-lAr^S.e-DichloronicotinoylJ-A^-t^-oxopent^'-en^'-ylJ-L-omithinynthiazolidine
(Formula Removed)
3-[N-(tert-ButyloxycarbonyO-Ar-fS.e-dichloronicotinoyO-L-ornithinylJthiazolidine (162mg, 0.34mmo!) was dissolved in 4M HCI/dioxan (20ml). The mixture was stirred for 1 hour at room temperature then the solvent was removed in vacuo. The residue was dissolved in dichloromethane (25ml) and 2,4-pentanedione (100mg, 0.37 mmol) and triethylamine (40mg, 0.4mmol) were added. The solution was stirred at room temperature for 18 hours then evaporated in vacuo. The residue was taken up in ethyl acetate (70ml). The solution was washed with sat NaHCO3, water and brine, dried (Na2SO4) and evaporated. The residue was purified by flash chromatography on silica gel (eluant: 90% ethyl acetate, 10% pet. ether 60-80) to give a white solid identified as S-tAT^S.e-dichloronicotinoyO-Ar^'-oxopent^'-en-^-yO-L-ornithihyllthiazolidine (63mg, O.Hmmol, 40%).
[M+Hj+ = 461.3
1H NMR (CDCI3): δ 1.74-1.86 (6H,m), 1.87 (3H,s), 1.97 (3H,s), 2.94-3.11 (2H,m), 3.46-3.51 (2H,m), 3.75-3.79 (1H,m), 4.48-4.57 (2H,m), 5.01 (1H,s), 7.60-7.90 (1H,m), 8.34 (1H,d,J=2.0Hz), 8.78 (1H,d,J=2.3Hz), 11.01 (1H,d,J=8.2Hz) ppm.
EXAMPLE 10
3-[AT-(Acetoxymethoxycarbonyl)-N0>-{3,4-dichlorobenzyl)-L-
glutaminyl]thiazolidine
(Formula Removed)
10A. 3-[W-(tert-Butyloxycarbonyl)-Oa>-methyl-L-glutamyl]thiazolidine
N-(tert-Butyloxycarbonyl)-O0,-methyl-L-giutamic acid (6.28g, 24mmol) was dissolved in CH2CI2/DMF (9:1, 100ml). To this solution at 0°C were added 1-hydroxybenzotriazole hydrate (5.5g, 36mmol), water-soluble carbodiimide (5.38g, 28mmol), thiazolidine (2.48g, 28mmol) and triethylamine (3.0g, 30mmol). The mixture was stirred for 18h at
0°C to room temperature then the solvent was removed in vacuo and the residue was taken up in ethyl acetate (150ml). The solution was washed with 0.3M KHSO4 (2 x 30ml), sat. NaHCO3 (2 x 30ml), water (2 x 30ml) and brine (1 x 30ml), dried (Na2SO4) and evaporated in vacuo. The residue was purified by flash chromatography on silica gel (eluant: 70% ethyl acetate, 30% pet. ether 60-80) to give a brown oil identified as 3-[N-(tert-butyloxycarbonyl)-O-methyl-L-glutamyl]thiazolidine (4.0g, 12mmol, 50%).
10B. 3-[N-(tert-Butyloxycarbonyl)-L-glutamyl]thiazolidine
3-[N-(rert-Butyloxycarbonyl)-O-methyl-L-glutamyl]thiazolidine (3.23g, 9.73mmol) was dissolved in THF (50ml). 1M Lithium hydroxide (11ml, 11mmol) was added. The mixture was stirred for 1 hour at room temperature then the solvent was removed in vacuo and the residue was taken up in ethyl acetate (70ml). The solution was washed with 1M KHSO2 (2 x 20ml), water (2 x 20ml) and brine (1 x 20ml), dried (Na2SO4) and evaporated in vacuo to give a colourless oil identified as 3-[N-(tert-butyloxycarbonyl)-L-glutamyl]thiazolidine (3.0g, 9.4mmol, 97%).
10C. 3-[N-(tert-Butyloxycarbonyl)-N-(3,4-dichlorobenzyl)-L-glutaminylJ-thiazolidine
3-[N-(tert-Butyloxycarbonyl)-L-glutamyl]thiazolidine (200mg, 0.63mmol) was dissolved in CH2CI2/DMF (9:1, 10ml). To this solution at 0°C was added 1-hydroxybenzotriazole hydrate (119mg, 0.76mmol), water-soluble carbodiimide (163mg, 0.88mmol), 3.4-dichlorobenzylamine (111mg, 0.83mmol) and triethylamine(126mg, 1.26mmol). The mixture was stirred for 18h at 0°C to room temperature then the solvent was removed in vacuo and the residue was taken up in ethyl acetate (70ml). The solution was washed with 0.3M KHSO4 (2 x 20ml), sat. NaHCO3 (2 x 20ml), water (2 x 20ml) and brine (1 x 20ml), dried (Na2SO4) and evaporated in vacuo to give a yellow oil. The residue was purified by flash chromatography on silica gel (eluant: ethyl acetate) to give a colourless oil identified as 3-[Nα-(tert-butyloxycarbonyl)-N-(3,4-dichlorobenzyl)-L-glutaminyl]thiazolidine (295mg, 0.62mmol, 98%).
10D. 3-[Nα-(Acetoxymethoxycarbonyl)-Nα-(3,4-dichlorobenzyl)-L-glutaminyl]-thiazolidine
3-[Na-(fe/t-Butyloxycarbonyl)-Ar-(3,4-dichlorobenzyl)-L-glutaminyl]thiazolidine (150mg, 0.32mmol) was dissolved in 4M HCI/dioxan (20ml). The mixture was stirred for 1 hour at room temperature then the solvent was removed in vacuo. The residue was
dissolved in dichloromethane (25ml) and acetoxymethyl p-nitrophenyl carbonate (95mg, 0.35mmol; prepared according to Alexander et a/., J. Med. Chem. 31, 318, 1988) and triethylamine (64mg, 0.64mmol) were added. The solution was stirred at room temperature for 18 hours then evaporated in vacuo. The residue taken up in ethyl acetate (70ml). The solution was washed with sat NaHCO3, water and brine, dried (Na2SO4) and evaporated. The residue was purified by flash chromatography on silica gel (eluant: ethyl acetate) to give a white solid identified as 3-[Nα-(acetoxymethoxycarbonyl)-N,-(3,4-dichlorobenzyl)-L-glutaminyl]thiazolidine (88mg, 0.18mmol, 56%).
[M+H]+ = 492.0
1H NMR (CDCI3): δ 1.44-1.46 (3H,m), 1.63-1.99 (3H,br m), 1.99-2.04 (4H,m), 2.98-3.06 (2H,m), 3.46-3.48 (2H,m), 3.50-3.80 (2H m), 4.47-4.56 (3H,m), 5.81-5.91 (1H.m), 6.74-6.75 (1H,m), 7.24-7.33 (1H,m), 8.24-8.25 (1H,m), 8.69-8.71 (1H,m) ppm.
EXAMPLE 11 1-[Nα-(1'-Acetoxyethoxycarbonyl)-N-(2-chloronicotinoyl)-L-ornithinyl]pyrrolidine
(Formula Removed)
11 A. 1-[N-(Benzyloxycarbonyl)-N-tert-butyloxycarbonyl)-L-ornithinyl]pyrrolidine
N-(Benzyloxycarbonyl)-Nα-(tert-butyloxycarbonyl)-L-ornithine (5.49g, 15mmol) was dissolved in CH2CI2/DMF (9:1, 100ml). To this solution at 0°C were added 1-hydroxybenzotriazole hydrate (3.37g, 22mmol), water-soluble carbodiimide (3.46g, 18mmol), pyrrolidine (1.28g, 18mmol) and triethylamine (200mg, 20mmol). The mixture was stirred for 18h at 0°C to room temperature then the solvent was removed in vacuo and the residue was taken up in ethyl acetate (200ml). The solution was washed with 0.3M KHSO4 (2 x 50ml), sat. NaHCO3 (2 x 50ml), water (2 x 50ml) and
brine (1 x 50ml), dried (Na2SO4) and evaporated in vacuo. The residue was purified by flash chromatography on silica gel (eluant: 90% ethyl acetate, 10% pet. ether 60-80) to give a colourless oil identified as 1-[N-(benzyloxycarbonyl)-N-(tert-butyloxycarbonyl)-L-ornithinyl]pyrrolidine (5.15g, 12.3mmol, 82%).
11B. 1-[Nα-(tert-Butyloxycarbonyl)-L-ornithinyl]pyrrolidine
To a solution of 1-[N-(benzyloxycarbonyl)-Ntert-butyloxycarbonyl)-L-ornithinyl]-pyrrolidine (2.15g, 5.13mmol) in methanol (80ml) was added 10% Pd/C (400mg). The mixture was stirred under a hydrogen atmosphere for 2 hours then the catalyst was filtered off and washed with methanol (50ml). The combined filtrates were evaporated in vacuo to give an off white solid identified as 1-[N-(tert-butyloxycarbonyl)-L-ornithinyljpyrrolidine (1.35g, 4.74mmol, 94%).
11C. 1-[N-(tert-Butyioxycarbonyl)-N-(2-chloronicotinoyl)-L-omithinyl]pyrrolidine
1-[N-(tert-Butyloxycarbonyl)-L-ornithinyl]pyrrolidine (204mg, 0.72mmol) was dissolved
in CH2CI2 (20ml). To this solution was added 2-chloronicotinoyl chloride (130mg,
0.74mmol) and triethylamine (200mg, 2.0mmol). The mixture was stirred for 18h at
0°C to room temperature then the solvent was removed in vacuo and the residue was
taken up in ethyl acetate (70ml). The solution was washed with 0.3M KHSO4 (2 x
20ml), sat. NaHCO3 (2 x 20ml), water (2 x 20ml) and brine (1 x 20ml), dried (Na2SO2)
and evaporated in vacuo. The residue was purified by flash chromatography on silica
gel (eluant: 10% methanol, 90% chloroform) to give a sticky white solid identified as 1-
[Nα-(tert-butyloxycarbonyl)-N-(2-chloronicotinoyl)-L-ornithinyl]pyrrolidine (236mg,
0.56mmol, 78%).
11D. 1-[Nα-(1'-Acetoxyethoxycarbonyl)-N-(2-chloronicotinoyl)-L-ornithinyl]-pyrrolidine
1-[Nα-(tert-Butyloxycarbonyl)-N-(2-chloronicotinoyl)-L-ornithinyl]pyrrolidine (206mg, 0.49mmol) was dissolved in 4M HCI/dioxan (20ml). The mixture was stirred for 1 hour at room temperature then the solvent was removed in vacuo. The residue was dissolved in dichloromethane (25ml) and a-acetoxyethyl p-nitrophenyl carbonate (140mg, 0.52 mmol; prepared according to Alexander et a/., J. Med. Chem. 31, 313, 1988) and triethylamine (40mg, 0.4mmol) were added. The solution was stirred at room temperature for 18 hours then evaporated in vacuo. The residue was taken up
in ethyl acetate (70ml). The solution was washed with sat NaHCO3, water and brine, dried (Na2SO4) and evaporated. The residue was purified by flash chromatography on silica gel (eluant: 92% chloroform, 8% methanol) to give a white solid identified as 1-[NQ-(1'-acetoxyethoxycarbonyl)-N-(2-chloronicotinoyl)-L-omithinyl]pyrrolidine (127mg, 0.28mmol, 57%).
[M+H]+ = 455.1
1H NMR (CDCI3): δ 1.42-1.49 (3H,m), 1.83-1.95 (8H,m), 2.02 (3H,d,J=1.5Hz). 3.32-3.71 (6H.m), 4.45-4.47 (1H,m), 5.75-5.85 (1H,m), 6.72-6.77 (2H.m), 7.27-7.33 (1H,m), 7.97-8.06 (1H,m), 8.40-8.43 (1H,m) ppm.

WE CLAIMS
1 A compound according to general formula 1
(Formula Removed)
or a pharmaceutically acceptable salt thereof, wherein:
R1 is H or CN,
R2 is selected from CH2R5, CH2CH2R5 and C(R3)(R4)-X2-(CH2)aR5,
R3 and R4 are each independently selected from H and Me;
R5 is selected from CON(R6)(R7), N(R8)C(=O)R9, N(R8)C(=S)R9, N(R8)SO2R10 and N(R8)R10;
R6 and R7 are each independently R11(CH2)b or together they are -(CH2)rZ-(CH2)2- or -CH2-o-C6H4-Z-CH2-;
R8 is H or Me;
R9 is selected from R11(CH2)b, R11(CH2)bO and N(R6)(R7);
R10 is R11(CH2)b;
R11 is selected from H, alky!, optionally substituted aryl, optionally substituted aroyl, optionally substituted arylsulphonyl and optionally substituted heteroaryl;
R12 is selected from H2NCH(R13)CO, H2NCH(R14)CONHCH(R15)CO, C(R16)=C(R17)COR18 and R19OCO;
R13, R14 and R15 are selected from the side chains of the proteinaceous amino
acids;
R16 is selected from H, lower alkyl (C1-C6) and phenyl;
R17 is selected from H and lower alkyl (C1-C6);
R18 is selected from H, lower alkyl (C1-C6), OH, 0-(lower alkyl (C1-C6)) and phenyl;
R19 is selected from lower alkyl (C1-C6), optionally substituted phenyl and R20C(=O)OC(R21)(R22);
R20, R21 and R22 are each independently selected from H and lower alkyl (C1-C6);
Z is selected from a covalent bond, -(CH2)C-, -O-, -SOσ and -N(R10)-;
X1 is S or CH2,
X2 is O, S or CH2;
a is 1, 2 or 3
b is 0 - 3;
c is 1 or 2; and
d is 0 - 2
2 A compound according to Claim 1 wherein R1 is H.
3 A compound according to Claim 1 wherein R1 is CN.
4 A compound according to any of Claims 1 to 3 wherein R2 is selected from
CH2CH2R5 and C(R3)(R4)-X2-(CH2)aR5.
5 A compound according to claim 2 or claim 3 wherein X1 is CH2. 6. A compound according to claim 1 or claim 2 wherein X1 is S.
7 A compound according to Claim 4 wherein R3 and R4 are both H, X2 is CH2
and a is 1 or 2.
8 A compound according to Claim 7 wherein R2 is selected from CH2CH2CH2R5
and CH2CH2CH2CH2R5.
9 A compound according to any of Claims 1 to 8 wherein R5 is CON(R6)(R7).
10 A compound according to any of Claims 1 to 4 and 6 to 8 wherein R5 is
selected from N(R8)C(=O)R9, N(R8)C(=S)R9, N(R8)SO2R10 and N(RB)R10.
11 A compound according to claim 5 wherein R5 is selected from CON(R6)(R7),
N(R8)C(=O)R9, N(R8)C(=S)R9 and N(R8)R10.
12 A compound according to any of Claims 1 to 11 wherein R12 is selected from
H2NCH(R13)CO and H2NCH(R14)CONHCH(R15)CO.
13 A compound according to any of Claims 1 to 11 wherein R12 is R19OCO.
14 A pharmaceutical composition comprising a compound according to any of
Claims 1 to 13.
15 The use for a compound according to any of Claims 1 to 13, which is as a
component in the preparation of a pharmaceutical composition.
16 A method of treatment of hyperglycaemia which comprises the administration
to an individual in need of such treatment of an effective amount of a compound according to any of Claims 1 to 13.
17 A compound or pharmaceutical composition according to any of Claims 1 to
14, a use according to claim 15 or 21 or a method according to any of claims claim 16 or 18 to 20, with the proviso that R19 is not t-butyl.
18 A method of treatment of a disease or medical condition in a human or animal which comprises the administration to an individual in need of such treatment of an effective amount of a compound according to general formula 1
(Formula Removed)
or a pharmaceutically acceptable salt thereof, wherein:
R1 is H or CN,
R2 is selected from CH2R5, CH2CH2R5 and C(R3)(R4)-X2-(CH2)aR5,
R3 and R4 are each independently selected from H and Me;
R5 is selected from CON(R6)(R7), N(R8)C(=O)R9, N(R8)C(=S)R9, N(R8)SO2R10 and N(R8)R10;
R6 and R7 are each independently R11(CH2)b or together they are -(CH2)2-Z-(CH2)2- or -CH2-o-C6H4-Z-CH2;
R8 is H or Me;
R9 is selected from R11(CH2)b, R11(CH2)bO and N(R6)(R7);
R10 is R11(CH2)b;
R11 is selected from H, alkyl, optionally substituted aryl, optionally substituted aroyl, optionally substituted arylsulphonyl and optionally substituted heteroaryl;
R12 is selected from H2NCH(R13)CO, H2NCH(R14)CONHCH(R15)CO, C(R16)=C(R17)COR18 and R19OCO;
R13, R14 and R15 are selected from the side chains of the proteinaceous amino acids;
R16 is selected from H, lower alkyl (C1-C6) and phenyl;
R17 is selected from H and lower alkyl (C1-C6);
R18 is selected from H, lower alkyl (C1- C6), OH, O-(lower alkyl (C1-C6)) and phenyl;
R19 is selected from lower alkyl (C1- C6), optionally substituted phenyl and R20C(=O)OC(R21)(R22);
R20, R21 and R22 are each independently selected from H and lower alkyl (C1-C6);
Z is selected from a covalent bond, -(CH2)C-, -O-, -SOd- and -N(R10)-;
X1 is S or CH2,
X2 is O, S or CH2;
a is 1,2 or 3
b is 0 - 3;
c is 1 or 2; and
d is 0 - 2
19 A method according to claim 18 in which the disease or medical condition is
impaired glucose tolerance, type II diabetes or hyperglycaemia.
20 A method according to claim 18 in which the disease or medical condition is
due to a DP-IV mediated process.
21 The use for a compound according to any of Claims 1 to 13, which is as a DP-
IV inhibitor, or as a prodrug for a DP-IV inhibitor.
22. A compound according to general formula 1, or a pharmaceutically
acceptable salt thereof substantially as herein described with reference
to the foregoing examples.
23. A pharmaceutical composition comprising a compound substantially as
herein described with reference to the foregoing examples.
24. The use for a compound substantially as herein described with reference
to the foregoing examples.
25. A method of treatment of hyperglycaemia substantially as herein
described with reference to the foregoing examples.
26. A method of treatment of a disease or medical condition in a human or
animal substantially as herein described with reference to the foregoing
examples.