Cyclohexyl Amide Derivatives and Their Use as CRF-1 Receptor Antagonists

There are described cyclohexyl amide derivatives useful as corticotropin releasing factor (CRF1) receptor antagonists.

To a stirred suspension of trans-4-amino-cyclohexylcarboxylic acid methyl ester hydrochloride (6.7 g, 34.7 mmol) in dry THF (90 mL) under nitrogen atmosphere is added triethylamine (12 mL, 86.8 mmol). The suspension is cooled to 0° C. and 2-chloro-5-(trifluoromethyl)benzoyl chloride (8.85 g, 36.4 mmol) in dry THF (40 mL) is added dropwise over 20 minutes. The resulting thick, colourless slurry is stirred at 0-5° C. for 30 minutes and then allowed to warm to room temp and stirred at room temp for 1 hour. The reaction is quenched by the dropwise addition of water (5 mL) in THF (45 mL) to give a clear solution. This is diluted with water (100 mL) and ethyl acetate (300 mL). The biphasic mixture is stirred for 5 minutes then the organic phase is separated and washed successively with water (100 mL), saturated sodium bicarbonate (100 mL) and saturated brine (100 mL), dried (MgSO4), filtered and evaporated to give a colourless solid; [MH+364].

To a solution of trans-4-(2-chloro-5-trifluoromethyl-benzoylamino)-cyclohexane carboxylic acid methyl ester (step 1)(95.2 g, 0.26 mol) in dry THF (10 under nitrogen at 0° C. is added lithium aluminium hydride pellets (20 g, 0.53 mol) portion wise over 3 hours. The reaction mixture is stirred at 0° C. for a further 2 hours and then carefully quenched at 0° C. by the addition of water (40 mL) in THF (60 mL) followed by further THF (500 mL) to maintain a mobile suspension. Finally, 1M sodium hydroxide solution (80 mL) is added at 0° C. resulting in a yellow solution containing a colourless suspension. The reaction is filtered through a Celite® pad (filter material) to remove inorganic salts. The Celite® pad/salts are washed with EtOAc (500 mL) then with EtOAc:THF (1:1; 300 mL). The organics are combined and diluted with further EtOAc (600 mL) and then washed with saturated brine (600 mL). The organic layer is dried (Na2SO4), filtered and concentrated under reduced pressure until a slurry is obtained. Et2O is added to the slurry, which is then stirred for 5 minutes before being filtered to recover a colourless solid. The solid is washed with isohexane and then dried at 35° C. under vacuum to give the required product.

To a stirred suspension of trans-2-chloro-N-(4-hydroxymethyl-cyclohexyl)-5-trifluoromethyl-benzamide (step 2)(24 g, 71.5 mmol) in DCM (72 mL) under N2supply at RT, is added triethylamine (29.7 mL, 214 mmol) followed by DMSO (24 mL), giving an almost homogenous solution. The mixture is cooled to 0° C. (ice/salt bath), and to this is added dropwise a solution/suspension of sulfur trioxide-pyridine complex (34.1 g, 214 mmol) in DMSO (30 mL): DCM (20 mL) over a period of ˜90 min. The mixture is stirred at 0-5° C. over a 1 h period then allowed to warm to RT over 2 h. The mixture is cooled to 0° C. in an ice bath and is quenched by the addition of 1 M HCl (aq) (40 mL) dropwise over 30 min. The mixture is then diluted with water (60 mL) and DCM (150 mL). 2 M HCl is added to give pH ˜1-2. The organic phase is separated, washed again with 2 M HCl (100 mL), followed by sat. NaHCO3(100 mL). The organic layer is diluted with EtOAc (800 mL) and is vigourously stirred at RT. The mixture is then filtered removing some insoluble material in the process. The now clear two phase mixture is separated, the organic (EtOAc) layer is dried over over MgSO4and is filtered and concentrated to give an off white solid. The crude solid is suspended in diethylether (500 mL) and is triturated, removing some brown/yellow colour. The solid is allowed to settle, and the liquors are decanted off. The solid is then triturated in iso-hexane (300 mL), using the same procedure twice, then the solid is transferred to a small flask in iso-hexane slurry and is dried in vacuo to give an off-white solid; [MH+334]

To a 100 mL round-bottomed flask containing trans-2-chloro-N-(4-formyl-cyclohexyl)-5-trifluoromethyl-benzamide (step 3) (900 mg, 2.70 mmol) and 2-amino-3-picoline (306 mg, 2.83 mmol) in dry DCM (30 mL) is added sodium triacetoxyborohydride (857 mg, 4.05 mmol) in one portion. The suspension is stirred at RT overnight. 1N sodium hydroxide (10 mL) is added and the mixture is stirred at RT for 10 min. The mixture is then extracted with DCM (3×75 mL). DCM extracts are combined, washed with sat. brine (50 mL), dried (MgSO4), filtered and evaporated to give a colourless solid. The crude product is redissolved in DCM, absorbed directly onto silica gel and columned on silica gel using a 40 g pre-packed column and isohexane/EtOAc gradient elution (0% to 100% EtOAc). Product is isolated as a colourless solid and is recrystallised from minimum amount of EtOAc containing isohexane (approx 10:1 iHex:EtOAc) to give 487 mg colourless crystals.

The compounds of the following tabulated Examples (Table 1) are prepared by a similar method to that of Example 1 using the appropriate benzamide or pyrazole starting materials (prepared analogously to trans-2-chloro-N-(4-formyl-cyclohexyl)-5-trifluoromethyl-benzamide from trans-4-amino-cyclohexylcarboxylic acid methyl ester hydrochloride and the appropriate benzoly chloride) and the appropriate amine.

The title compound is prepared from Trans-2-Chloro-N-{4-[(5-formyl-pyridin-2-ylamino)-methyl]-cyclohexyl}-5-trifluoromethyl-benzamide and dimethylamine hydrochloride analogously to Example 1.

Ethyl 2-methyl-4-oxocyclohex-2-enecarboxylate (2.0 g, 10.98 mmol) is dissolved in MeOH (40 ml) and water (4.0 ml) to give a yellow solution. Ammonium formate (8.31 g, 132 mmol) is added and stirred at RT until the suspension dissolves to form a solution. Palladium on carbon (0.117 g, 1.098 mmol) is added and the reaction mixture is stirred at 70° C. for 1 hour. The mixture is filtered through Celite® (filter material) and washed with MeOH. The filtrate is concentrated in vacuo and the residue is partitioned between EtOAc and water. The aqueous portion is diluted with sat. sodium bicarbonate and washed with EtOAc. The pH is adjusted to pH14 using 1M NaOH and the aqueous is extracted with EtOAc. The combined organic extracts are dried MgSO4, filtered and concentrated in vacuo to afford the title compound; [MH]+186.24.

Ethyl 4-amino-2-methylcyclohexanecarboxylate (780 mg, 4.21 mmol) in THF (10 ml) is treated with TEA (1.174 ml, 8.42 mmol) and the reaction mixture is cooled to 0° C. 2-Chloro-5-(trifluoromethyl)benzoyl chloride (921 mg, 3.79 mmol) is added dropwise and the reaction mixture is stirred and allowed to warm to RT. After 3 hours, the reaction is quenched with water and partitioned between EtOAc and sat. sodium bicarbonate. The organic portion is separated and dried over MgSO4and concentrated in vacuo to afford the title compound which is used without further purification. [MH]+392.26.

The title compound is prepared analogously to Example 1 by replacing trans-4-(2-chloro-5-trifluoromethyl-benzoylamino)-cyclohexane carboxylic acid methyl ester (Ex. 1 Step 2) with ethyl 4-(2-chloro-5-(trifluoromethyl)benzamido)-2-methyl cyclohexane carboxylate (Ex. 1.35 step 2) and by replacing 2-amino-3-picoline (Ex. 1 step 4) with 5-(4-fluorophenyl)-1H-pyrazol-3-amine. [MH]+509.40.

Separation and isolation of 1.35a (+/−)-2-Chloro-N-((1S,3R,4S)-4-{[5-(4-fluoro-phenyl)-1H-pyrazol-3-ylamino]-methyl}-3-methyl-cyclohexyl)-5-trifluoromethyl-benzamide and 1.35b (+/−)-2-Chloro-N-((1S,3S,45)-4-{[5-(4-fluoro-phenyl)-1H-pyrazol-3-ylamino]-methyl}-3-methylcyclohexyl)-5-trifluoromethyl-benzamide from a 90 mg sample of the crude reaction mixture was carried out by Supercritical Fluid Chromatography followed by preparative mass directed reverse phase HPLC, using the following methods:

7 mg of 1.35a (+/−)-2-Chloro-N-((1S,3R,45)-4-{[5-(4-fluoro-phenyl)-1H-pyrazol-3-ylamino]-methyl}-3-methyl-cyclohexyl)-5-trifluoromethyl-benzamide was isolated with a retention time of 10.48 min.

Impure fractions centred around retention time 9.15 min were combined and purified by preparative mass directed reverse phase HPLC

(2) Preparative Mass Directed Reverse Phase HPLC

The impure fractions from the SFC purification above were purified by the following method

11 mg of (+/−)-2-Chloro-N-((1S,3S,4S)-4-{[5-(4-fluoro-phenyl)-1H-pyrazol-3-ylamino]-methyl}-3-methyl-cyclohexyl)-5-trifluoromethyl-benzamide was isolated with retention time 7.70 min

EXAMPLES 2.1 TO 2.46

The compounds of the following tabulated Examples are prepared using the following general procedure:

A stock solution of trans-2-chloro-N-(4-formyl-cyclohexyl)-5-trifluoromethyl-benzamide (Example 1 Step 3) is made up in dry THF (5.5 g in 88 mL). 800 ul of aldehyde solution is pipetted into each vial of pre-weighed amine (1.2 eq, 0.18 mmol). A stock solution of acetic acid is made up in dry THF (2.56 mL in 22 mL THF). Acetic acid stock solution (200 μl) is pipetted into each vial. MP-triacetoxyborohydride resin (>2.5 eq, >0.374 mmol, ˜200 mg) is added to each vial. Vials are sealed and shaken at RT for 16 hours. Crude reaction mixtures are passed onto a 1 g SCX-2 cartridge (Biotage) under gravity, which had been pre-wetted with 1 mL MeOH. The cartridges are washed with 2×2 mL MeOH, then compounds eluted with 2×2 mL 2M ammonia in MeOH. Compounds are analysed and evaporated in vacuo. Crude mixtures are purified further by prep HPLC (Waters Sunfire C18 5 micron column, 19×50 mm, mobile phases 0.1% TFA in water, 0.1% TFA in acetonitrile, 6 minute gradient dependant on retention time from analytics). Successful purifications are turned into free-based amines by passing prep fraction through a SCX-2 cartridge pre-wetted with MeOH, washed with 5 mL MeOH, and eluted with 2×2 mL 3.5M ammonia in MeOH. Finally, compounds are evaporated in vacuo.

800 mg (2.40 mmol) of trans-2-chloro-N-(4-formyl-cyclohexyl)-5-trifluoromethyl-benzamide (Example 1 Step 3) and 274 mg (2.40 mmol) of 5-methylthiazol-2-amine are placed in a flask with 40 mL of DCM. 191 mg (3.60 mmol) of sodium triacetoxyborohydride is added and the RM is stirred at room temperature overnight 1N sodium hydroxide (2 mL) is added and the mixture is stirred at RT for 10 min. The RM is partitioned between DCM and water. The organic phase is washed with water and brine, dried over MgSO4, filtered and the solvent is removed in vacuo. The product is purified by ISCO Combiflash Rf (80 g Si, iso-hexane->EtOAc, default setting). The product crystallised out on the column and had to be eluted with EtOAc (10% MeOH). The solvent is removed in vacuo and the product is crystallised from EtOAc, filtered and dried for 4 days under vacuum @ 50° C.

EXAMPLES 4.1 TO 4.33

The compounds of the following tabulated Examples are prepared using the following general procedure:

A stock solution of trans-2-chloro-N-(4-formyl-cyclohexyl)-5-trifluoromethyl-benzamide (Example 1 Step 3) (3.102 g) and acetic acid (1.6 mL) is prepared in 23.5 mL DMF (peptide grade). Each microwave vial is loaded with MP-triacetoxyborohydride resin (˜100 mg). 267 μl of the acetic acid/aldehyde solution is added to each microwave vial. Each amine is solubilised in 750 μl DMF and added to the microwave vials. The vials are sealed and heated to 60° C. for 10 minutes in the microwave synthesiser. The crude reactions are passed onto a 1 g SCX-2 cartridge (Biotage) under gravity, which had been pre-wetted with 1 mL MeOH. The cartridges are washed with 2×2 mL MeOH, then compounds eluted with 2×2 mL 2M ammonia in MeOH. Compounds are analysed and evaporated in vacuo. Crude mixtures are purified further by prep HPLC (Waters Sunfire C18 5 micron column, 19×50 mm, mobile phases 0.1% TFA in water, 0.1% TFA in acetonitrile, 6 minute gradient dependant on retention time from analytics). Successful purifications are turned into free-based amines by passing prep fraction through a SCX-2 cartridge pre-wetted with MeOH, washed with 5 mL MeOH, and eluted with 2×2 mL 3.5M ammonia in MeOH. Compounds are evaporated in vacuo.

EXAMPLES 5.1 TO 5.17

Preparation of Intermediate Compound Trans-(4-Amino-cyclohexylmethyl) phenylamine

Methyl trans-4-aminocyclohexanecarboxylate (43 g, 222 mmol) is added to MeOH (500 mL) to give a colourless solution. The solution is cooled to 10° C. and triethylamine (46.4 mL, 333 mmol) is added dropwise, followed by a solution of di-tert-butyldicarbonate (53.3 g, 244 mmol) in MeOH (400 mL) over 20 minutes. The reaction is warmed to room temperature and stirred at room temperature overnight. The mixture is evaporated to dryness under reduced pressure. The resulting colourless solid is dissolved in EtOAc (1000 mL) and the solution obtained is washed successively with 10% citric acid solution (100 mL), saturated sodium bicarbonate solution (2×100 mL) and saturated brine (100 mL); dried (MgSO4) and evaporated under reduced pressure to give a colourless solid.

Methyl trans-4-(tert-butoxycarbonylamino)cyclohexanecarboxylate (55.5 g, 216 mmol) is suspended in ethanol (900 mL) and THF (100 mL) and the mixture is cooled to 5° C. Granular calcium chloride (47.9 g, 431 mmol) is added portionwise to give a milky suspension. Sodium borohydride (32.6 g, 863 mmol) is added portionwise over 25 mins at 5° C. The reaction mixture (white emulsion) is stirred at 5° C. for 1 hour, the water bath is removed and then the reaction mixture is allowed to warm to room temperature and stirred at room temperature overnight. The reaction mixture is cooled to 10° C. and 5% potassium carbonate (200 mL) is added dropwise until the pH of the solution is pH11. A colourless precipitate formed which is filtered off. The solid is stirred with ethyl acetate (2000 mL) and water (500 mL). The organic layer is separated and washed with 0.5M HCl (200 mL), then washed with water (2×200 mL) and saturated brine (100 mL). The organic solution is dried over anhydrous MgSO4, filtered and evaporated to give a white solid. The solid is dried under high vacuum overnight to constant weight; [MH+230].

To trans-tert-butyl-4-(hydroxymethyl)cyclohexylcarbamate (8.0 g, 34.9 mmol) in DCM (180 mL) and DMSO (60 mL) at 0° C. is added DIPEA (24.37 mL, 140 mmol) and pyridine sulfur trioxide (22.21 g, 140 mmol) dissolved in DMSO (60 mL). The mixture is stirred at room temperature for 15 minutes and then is partitioned between 1M HCl and diethylether. The organic phase is separated and washed with 1M HCl, water then saturated brine. The mixture is dried (MgSO4) and solvent evaporated to give the expected product; [MH+MeCN]+269.

Trans-(4-Formyl-cyclohexyl)carbamic acid tert-butyl ester (3.27 g, 14.38 mmol) and aniline (1.98 mL, 15.81 mmol) are dissolved in dichloromethane (60 mL) at room temperature. Sodium triacetoxyborohydride (4.57 g, 21.57 mmol) is added in one portion and the mixture is stirred at room temperature for 2.5 hours. 1N sodium hydroxide solution (20 mL) is added and the mixture is stirred at room temperature for a further 10 minutes. The DCM layer is separated and washed successively with water and saturated brine, dried (MgSO4), filtered and evaporated to give a colourless solid. This is slurried with iso-hexane, filtered and dried to give a colourless solid; [MH+305]

Trans-(4-Phenylaminomethyl-cyclohexyl)carbamic acid tert-butyl ester (4.37 g, 14.35 mmol) is dissolved in dry dichloromethane (200 mL) under a nitrogen atmosphere and trifluoroacetic acid (70 mL) is added dropwise at room temperature. The reaction mixture is stirred at room temperature for 3 hours before the volatiles are removed under reduced pressure. The residue is redissolved in DCM and washed with 1N sodium hydroxide solution. The DCM is then separated, washed sequentially with water and saturated brine and evaporated under reduced pressure, whereupon a beige solid is formed; [MH+205]

The compounds of the following tabulated Examples (Table 4) are prepared according from trans-(4-amino-cyclohexylmethyl)phenylamine (Ex. 5.1 step 5) according to the following general procedure:

A stock solution of trans-(4-amino-cyclohexylmethyl)phenylamine is made up in DMF (1.428 g in 13.6 mL). A stock solution of HATU is made up in DMF (3.808 g in 20.4 mL DMF). Ca. 60 mg PS-DIEA is added to each pre-weighed carboxylic acid. 200 ul Trans-(4-amino-cyclohexylmethyl)phenylamine solution is pipetted into each vial, followed by 300 μl of HATU solution. Vials are sealed and shaken at RT for 16 hr. Crude reactions are purified by loading onto a 1 g SCX-2 cartridge pre-wetted with MeOH, crude is washed with 3 mL MeOH before compounds are eluted with 2×2 mL 2M ammonia in MeOH. Compounds are analysed and evaporated in vacuo. Crude mixtures are purified further by prep HPLC (Waters Sunfire C18 5 micron column, 19×50 mm, mobile phases 0.1% TFA in water, 0.1% TFA in acetonitrile, 6 minute gradient dependant on retention time from analytics). Successful purifications are turned into free-based amines by passing prep fraction through a SCX-2 cartridge pre-wetted with MeOH, washed with 5 mL MeOH, and eluted with 2×2 mL 3.5M ammonia in MeOH. Compounds are evaporated in vacuo.

1-(1H-pyrazol-3-yl)imidazolidin-2-one (410 mg, 2.69 mmol) is placed in a microwave vial with acetonitrile (12 mL). NaH (60%, 108 mg, 2.69 mmol) is added and the reaction mixture is stirred at RT for 30 minutes. Trans-(4-(2-chloro-5-(trifluoromethyl)benzamido)cyclohexyl)methyl 4-methylbenzenesulfonate (1.20 g (0.20 mmol) is added and the mixture is heated using microwave radiation at 120° C. for 30 minutes. The mixture is partitioned between DCM and water. The organic phase is washed with water and brine, dried over MgSO4, filtered and the solvent was removed in vacuo. The product is purified by crystallisation (EtOAc with a small amount of MeOH) to afford the title compound.

The compounds of the following tabulated Examples (Table 5), or tautomers thereof, are prepared by a similar method to that of Example 6 by replacing 1-(1H-pyrazol-3-yl)imidazolidin-2-one with the appropriate intermediate. One such intermediate is 1-(5-Methyl-1H-pyrazol-3-yl)-imidazolidin-2-one, the preparation of which is described as follows:

To a solution of 5-Methyl-1H-pyrazol-3-ylamine (7.5 g, 77.2 mmol) in THF (150 mL) at 0° C. was added 2-chloroethylisocyanate (25 g, 236.9 mmol) and then the reaction mixture was stirred at RT for 18 h. Hexane was added to the reaction mixture, cooled to 0° C. and stirred for ˜2 h. The white solid precipitated out was collected by filtration, washed with diethylether and dried.

To a solution of 3-[3-(2-Chloro-ethyl)-ureido]-5-methyl-pyrazole-1-carboxylic acid (2-chloro-ethyl)-amide (14.5 g, 47.05 mmol) in THF (100 mL) was added sodium ethoxide solution prepared from sodium (2.2 g, 95.65 mmol) and ethanol (100 mL) and then the reaction mixture was stirred at RT for 20 h. Precipitation of white solid was observed. The reaction mixture was cooled to 0° C. and stirred for ˜2 h. The precipitated solid was collected by filtration, washed with ethanol and water, and dried under vacuum.

A solution of 3,5-dimethylpyrazole (51.4 mg, 0.534 mmol) in MeCN (2 ml) is treated with sodium hydride (14.11 mg, 0.588 mmol) and the reaction mixture is stirred 10 minutes. Trans-4-(2-Chloro-5-(trifluoromethyl)benzamido)cyclohexyl)methyl trifluoromethanesulfonate (250 mg, 0.534 mmol) is added and the mixture is stirred at RT for 2 hrs.

The compounds of the following tabulated Examples (Table 6), or tautomers thereof, are prepared from trans-4-(2-chloro-5-(trifluoromethyl)benzamido)cyclohexyl)methyl trifluoromethanesulfonate by a similar method to that of Example 7.0 using the appropriate azole.

1M sodium hydroxide solution (2 mL) is added and the mixture is stirred at room temp for 10 minutes. The mixture is passed through a phase separator and evaporated to give a colourless oil. The crude mixture is re-dissolved in the minimum amount of DCM, applied to a prepacked 12 g silica gel column and eluted with 0-100% EtOAc/isohexane gradient elution over 6 minutes, then 100% EtOAc for 8 minutes. Pure product is recovered as a colourless oil. The oil is dissolved in the minimum amount of DCM and triturated/sonicated with 9:1 isohexane/EtOAc to give a colourless solid, 31 mg, [MH+441.36].

To a 50 mL round-bottomed flask containing trans-2-chloro-N-(4-formyl-cyclohexyl)-5-trifluoromethyl-benzamide (Ex. 1 step 3) (1.0 g, 3.0 mmol) and 3-fluoroaniline (0.29 mL, 3.0 mmol) in dry DCM (25 mL) is added sodium triacetoxyborohydride (953 mg, 4.49 mmol) in three portions over 1-2 minutes. The suspension is stirred at RT for 1 hour. 1N sodium hydroxide (25 mL) is added and the mixture is stirred at RT for 20 min. The mixture is then diluted with DCM (50 mL) and the DCM layer separated and washed with 1M HCl (25 mL) and brine (15 mL), dried (MgSO4), filtered and evaporated to give a colourless solid. The crude product is redissolved in DCM, absorbed directly onto silica gel and columned on silica gel using a 50 g pre-packed column and eluted with 30% EtOAc/isohexane. Product is isolated as a colourless oil which is triturated with diether ether-isohexane to afford the title compound as colourless crystals. [MH+429.24].

To a 50 mL round-bottomed flask containing trans-2-chloro-N-(4-formyl-cyclohexyl)-5-trifluoromethyl-benzamide (Ex. 1 step 3) (100 mg, 0.3 mmol) and 3-amino-5-methylpyridine (36 mg, 0.3 mmol) in dry DCM (5 mL) is added sodium triacetoxyborohydride (106 mg, 0.45 mmol) in one portion. The suspension is stirred at RT for 4 hours. The mixture is partitioned between DCM and saturated sodium bicarbonate, passed through a phase separator to recover the DCM layer and evaporated to give a colourless solid. The crude product is redissolved in DCM, absorbed directly onto silica gel and columned on silica gel using a 12 g pre-packed column and isohexane/EtOAc gradient elution (0% to 100% EtOAc). Product-containing fractions are combined and evaporated and the product is isolated as a colourless solid after trituration with 20% EtOAc/isohexane, 55 mg, [MH+426.40].

To a 25 mL round-bottomed flask is added trans-2,5-dichloro-N-(4-formylcyclohexyl)benzamide (200 mg, 0.666 mmol) and N-methyl-1-(3-phenyl-1H-pyrazol-5-yl)methanamine oxalate (277 mg, 0.999 mmol) in DCM (15 mL) to give a colorless solution. Acetic acid (0.153 mL, 2.67 mmol) and sodium triacetoxyborohydride (424 mg, 1.999 mmol) are added and the mixture stirred at room temp for 90 minutes. 1M sodium hydroxide solution (4 mL) is added and the mixture is stirred at room temp for 10 minutes. The mixture is passed through a phase separator and evaporated to give a colourless oil. The crude mixture is re-dissolved in the minimum amount of DCM and applied to a pre-packed 12 g silica gel column and eluted with 0-100% EtOAc/isohexane over 6 minutes then 100% EtOAc for 8 minutes. Pure product is recovered as a colourless oil. The oil is dissolved in the minimum amount of DCM and triturated/sonicated with 9:1 isohexane/EtOAc to give a colourless solid 124 mg, [MH+471.30].

To a 7 mL vial equipped with magnetic stirrer bar is added (4-Amino-cyclohexylmethyl)-phenyl-amine (41 mg, 0.2 mmol), 3-chlorobenzoyl chloride (20 mg, 0.16 mmol) and DCM (2 mL) followed by trethylamine (42 μL, 0.3 mmol). The mixture is stirred at room temperature under nitrogen atmosphere for 3 hours. The mixture was then evaporated to dryness and purified directly by preparative HPLC, [MH+343.19].

The compounds of the following tabulated Examples (Table 7), or tautomers thereof, are prepared by a similar method to that of Example 12 using the appropriate acid chloride.

To a solution of trans-N-(4-formyl-cyclohexyl)-3-trifluoromethyl-benzamide (prepared analogously to trans-2-chloro-N-(4-formyl-cyclohexyl)-5-trifluoromethyl-benzamide (Ex. 1 step 3) from the appropriate starting compounds) (100 mg, 0.33 mmol) and 5-aminoquinoline (48 mg, 0.33 mmol) in dry 1,2-dichloroethane (2 mL) in a 2-5 mL capacity microwave tube, is added acetic acid (0.06 mL, 1.0 mmol) and sodium triacetoxyborohydride (178 mg, 0.84 mmol). The tube is sealed with a septum and the mixture is heated at 140° C. for 10 minutes in a Biotage Initiator microwave. After cooling to room temperature, the solvents are removed under reduced pressure and the residue is purified by chromatography on a pre-packed reverse phase column. [MH+428.45].

The compounds of the following tabulated Examples (Table 8) are prepared by a similar method to that of Example 13 using the appropriate amine.

To a solution of cis-(4-Amino-cyclohexyl)-methanol (Tetrahedron Lett., 1970, 11, 4285-4288) (0.75 g, 5.80 mmol) in THF (10 ml) is added water (1.8 mL), triethylamine (2.023 mL, 14.51 mmol) and 2-chloro-5-(trifluoromethyl)benzoyl chloride (1.411 g, 5.80 mmol). The RM is stirred at RT for 1 hour. The reaction mixture is partitioned between EtOAc and water. The organic phase is washed successively with water, saturated sodium bicarbarbonate and saturated brine, dried over MgSO4, filtered and the solvent removed in vacuo. Purification by chromatography on a pre-packed silica gel column using 0-100% EtOAc in isohexane gradient elution gave the desired product as a colourless solid.

To a solution of Cis-2-chloro-N-(−4-(hydroxymethyl)cyclohexyl)-5-(trifluoromethyl)-benzamide (1 g, 2.98 mmol) in DCM (18 mL) is added DIPEA (2.081 mL, 11.91 mmol). The reaction mixture is cooled to 0° C. and pyridine-sulfur trioxide (1.896 g, 11.91 mmol) in DMSO (6 mL) is added. The reaction mixture is stirred at this temperature for 30 mins. The reaction mixture is partitioned between water and DCM and passed through a phase separator. The DCM layer was collected and concentrated under reduced pressure to give a colourless oil. Purification by chromatography on a pre-packed silica gel column using 0-100% EtOAc in isohexane gradient elution gave the desired product as a colourless solid.

To a solution of Cis-2-Chloro-N-(4-formyl-cyclohexyl)-5-trifluoromethyl-benzamide (100 mg, 0.300 mmol) in DCM (3 mL) is added 3-(4-fluorophenyl)-1H-pyrazol-5-amine (58.4 mg, 0.330 mmol) to give a pale orange solution. This is stirred for 10 mins at room temperature before sodium triacetoxyborohydride (102 mg, 0.479 mmol) is added. The reaction mixture is stirred at room temperature for 1 hour. The reaction mixture is quenched by the addition of saturated sodium bicarbonate. The DCM layer is separated and further washed with water. The aqueous extracts are combined and re-extracted with DCM. The combined organic extracts are then dried over MgSO4, filtered and concentrated under vacuum. Purification by chromatography on a pre-packed 12 g silica gel column using 0-100% EtOAc in isohexane (gradient elution) gave the desired product as a colourless solid. [MH+495.29].

The title compound is prepared analogously to Example 14 using the appropriate amine in step 3; [MH+426.39].

To a solution of trans-2-chloro-N-(4-formylcyclohexyl)-5-(trifluoromethyl)-benzamide (1.00 g, 3.00 mmol) in THF (50 mL) is added methylmagnesium bromide 2.5 mL of a 3M solution in THF, 7.49 mmol) and the reaction mixture is stirred at room temperature for 1 hour. The reaction mixture is quenched with water and partitioned between EtOAc and water. The organic phase is washed with water and brine, dried over MgSO4, filtered and the solvent is removed in vacuo. The mixture is used directly in step 2 without further purification.

To a solution of Trans-2-chloro-N-(−4-((S)-1-hydroxyethyl)-cyclohexyl)-5-(trifluoromethyl)benzamide (1.00 g, 2.86 mmol) in DCM (20 mL) is added DIPEA (1.48 g, 11.4 mmol) of DIPEA. The reaction mixture is cooled to 0° C. and then a solution of sulfur trioxide-pyridine complex (1.82 g, 11.4 mmol) in DMSO (5 mL) is added. The reaction mixture is stirred at 0° C. for 10 min and then partitioned between DCM and water. The organic phase was washed with water and brine, dried over MgSO4, filtered and the solvent was removed in vacuo. Purification by chromatography on a pre-packed 40 g silica gel column using 0-100% EtOAc in isohexane (gradient elution) gave the desired product as a colourless solid.

To a solution of Trans-N-(4-acetylcyclohexyl)-2-chloro-5-(trifluoromethyl)-benzamide (200 mg, 0.57 mmol) and aniline (54 mg, 0.57 mmol) in DCM (10 mL) is added DMF (0.1 mL) followed by trichlorosilane (78 mg, 0.57 mmol). After stirring at room temperature for 1 hour, further trichlorosilane (5×78 mg, 5×0.57 mmol) is added at 1 hour intervals for the next 5 hours. Further DMF (0.1 mL) was then added and the mixture is stirred at room temperature overnight. The colourless solid that is formed is recovered by filtration, washed successively with water and then EtOAc and dried. [MH+425.38]. The racemic mixture was separated by supercritical fluid chromatography on chiral stationary phase analogously to that reported for Example 1.37.

Ethyl 4-oxocyclohexane carboxylate (10.0 g, 58.8 mmol) and pyrrolidine (5.87 g, 82.7 mmol) in toluene (100 mL) and molecular sieves (40 g of 4 Å sieves) are heated to reflux overnight using Dean Stark apparatus. The mixture is filtered and the excess pyrrolidine is removed in vacuo. The resulting mixture is diluted with toluene (50 mL) and treated with methyl iodide (8.96 g, 63.1 mmol). After heating at reflux for 15 hours, the mixture is allowed to cool to RT and silica (3 g) and water (30 mL) are added. The mixture is stirred at RT for 3 hours and partitioned between water and diethyl ether. The organic portion is separated and washed with water, brine, dried (MgSO4) and concentrated in vacuo. Purification by chromatography on silica eluting with iso-hexane:EtOAc (19:1 increasing to 9:1) affords the title compound.1H NMR (400 MHz, DMSO-d6) δ 4.15 (2H, q), 2.89 (1H, m), 2.51 (1H, m), 2.38 (1H, m), 2.21 (3H, m), 1.89 (1H, m), 1.62 (1H, m), 1.22 (3H, t), 0.95 (3H, d).

A mixture comprising toluene-4-sulfonic acid 4-benzylamino-3-methyl-cyclohexylmethyl ester (350 mg, 0.90 mmol), aniline (126, mg, 1.35 mmol) and potassium carbonate (250 mg, 1.80 mmol) in MeCN (1 mL) is heated using microwave radiation at 180° C. for 1 hour. The reaction mixture is partitioned between DCM and water and passed through a phase separator. The solvent is removed in vacuo and purification of the crude residue by chromatography on silica eluting with iso-hexane:EtOAc (25:1 increasing to 10:1) affords the title compound. [MH+309.34].

(4-Benzylamino-3-methyl-cyclohexylmethyl)-phenyl-amine (160 mg, 0.52 mmol) and ammonium formate (164 mg, 2.60 mmol) in EtOH (5 mL) is treated with 10% Pd/C (30 mg) and heated at reflux for 2 hours. The Pd/C is removed by filtration and washed with MeOH. The filtrate is concentrated in vacuo to afford the title compound which is used without further purification.

The racemate is separated into the component enantiomers by chiral chromatography on a Daicel Chiralpak AS column, 250 mm×20 mm (serial number AS00CJ-DD004)

5-Chloro-2-methyl-nicotinic acid (4.15 g, 24.2 mmol) is placed in a flask with DCM (100 mL) and oxalyl chloride (3.68 g, 29 mmol). DMF (200 μL) is added and the reaction mixture is stirred at r.t. for 1 hour (gas evolution). The mixture is filtered and the solvent is removed in vacuo to afford the title product which is used in the next step without further purification.

Trans-4-[(5-Chloro-2-methyl-pyridine-3-carbonyl)-amino]-cyclohexanecarboxylic acid methyl ester (step 2) (2.20 g, 7.08 mmol) is placed in a flask with dry THF (100 mL). This is cooled to 0° C. and lithium aluminum hydride (0.537 g, 14.16 mmol) is added. The reaction mixture is stirred at r.t. for 2 hours and then quenched with water (0.5 mL), 2M NaOH (0.5 mL) and then water again (1.5 mL). The solids are filtered off through Celite® (filter material) and the filtrate is partitioned between EtOAc and water. The organic phase is washed with water and brine, dried over MgSO4, filtered and the solvent is removed in vacuo to afford the title product which is used in the next step without further purification.1H NMR (400 MHz, DMSO-d6) δ 8.53 (1H, d), 8.38*1H, d), 7.79 (1H, d), 4.40 (1H, t), 3.66 (1H, m), 3.21 (2H, t), 2.47 (3H, s), 1.92 (2H, m), 1.78 (2H, m), 1.31 (1H, m), 1.22 (2H, m), 0.98 (2H, m). [MH]+283.30.

A solution of Trans-5-chloro-N-(4-hydroxymethyl-cyclohexyl)-2-methyl-nicotinamide (step 1) (100 mg, 0.354 mmol) and pyridine (3.6 ml) in dry DCM (3.5 ml) under nitrogen is cooled to approx. 0° C. using an ice-water bath. Methanesulfonyl chloride (0.030 ml, 0.389 mmol) is added dropwise. The reaction mixture is allowed to warm to room temp and stirred at this temp for 4 hours. The reaction is quenched by the addition of sat. NH4Cl at room temp and then extracted with diethyl ether (3×20 ml). The Et2O extracts are combined, washed with sat brine (20 mL), dried (MgSO4), filtered and evaporated to give the title compound as a colourless solid.

3,5-Dimethyl-1H-pyrazole (1.00 g, 10.4 mmol) is dissolved in chloroform (10 mL). N-Chlorosuccinimide (1.39 g, 10.4 mmol) is added and the reaction mixture is stirred at RT for 1 hour. The mixture is partitioned between chloroform and water. The organic phase is washed with water and brine, dried over MgSO4, filtered and the solvent is removed in vacuo to afford the title product;1H NMR (400 MHz, DMSO-d6) δ 12.5 (1H, broad), 2.12 (6H, s).

To a stirred solution of trans-tert-butyl 4-(hydroxymethyl)cyclohexylcarbamate (Ex 5.1 step 2) (1 g, 4.36 mmol) and dry pyridine (0.423 mL, 5.23 mmol) in dry DCM (45 mL) at 0° C. is added trifluoromethanesulfonic anhydride (0.81 mL, 4.8 mmol). The mixture is stirred at 0° C. for 1 hour and then allowed to warm to room temp. TLC analysis (isohexane:EtOAc, 1:2; stained with phosphomolybdic acid in EtOH) shows that the starting alcohol had been consumed and a new, less polar product had been formed. The reaction is quenched with saturated ammonium chloride solution (30 mL) and the DCM layer is separated using a phase separator, dried (MgSO4), filtered and evaporated to give the title compound as a pale yellow solid. This is used in the next step without further purification;1H NMR (400 MHz, CDCl3) δ 4.40 (1H, m), 4.35 (2H, d), 3.41 (1H, m), 2.12 (2H, m), 1.89 (2H, m), 1.80 (1H, m), 1.46 (9H, s), 1.16 (4H, m).

To a stirred solution of 3,4,5-trimethyl-1H-pyrazole (84 mg, 0.761 mmol) in dry acetonitrile (4 mL) at room temp is added sodium hydride (33 mg of a 60% dispersion on mineral oil, 0.83 mmol). The mixture is stirred at room temp for 10 minutes and then treated with a solution of trans-trifluoro-methanesulfonic acid 4-tert-butoxycarbonylamino-cyclohexylmethyl ester (step 1) (250 mg, 0.692 mmol) in dry acetonitrile (3 mL). The reaction mixture is stirred at room temp for 17 hours. The mixture is diluted with water (20 mL) and extracted with EtOAc (3×10 mL). The EtOAc extracts are combined, washed with brine (20 mL), dried (MgSO4), filtered and evaporated to give the title compound as a colourless oil. This is used in the next step without further purification; MS m/z 322.4 [M+H]+.

To a stirred solution of trans-[4-(3,4,5-trimethyl-pyrazol-1-ylmethyl)-cyclohexyl]-carbamic acid tert-butyl ester (step 2)(215 mg, 0.669 mmol) in methanol (3 mL) at room temp is added a solution of 4M HCl in dioxane (3 mL). The mixture is stirred at room temp for 1 hour and then concentrated in vacuo. The resulting gum is dried under vacuum overnight to afford the title compound which is used without further purification.1H NMR (400 MHz, CDCl3) δ 8.16 (3H, br s), 4.10 (2H, d), 2.90 (1H, m), 2.29 (3H, s), 2.27 (3H, s), 2.01-1.90 (5H, m including 3H, s), 1.83 (1H, s), 1.54 (2H, m), 1.30 (2H, m), 1.12 (2H, m). (NMR shows contamination with side products and solvents.)

EXAMPLES 22.6 AND 22.7

To a stirred solution of 5-methyl-3-(trifluoromethyl)-1H-pyrazole (199 mg, 1.328 mmol) in dry acetonitrile (7 mL) at room temp is added sodium hydride (63 mg of a 60% dispersion on mineral oil, 2.66 mmol). The mixture is stirred at room temp for 10 mins after which the initial effervescence had subsided to leave a colourless solution. A solution of trans-trifluoro-methanesulfonic acid 4-tert-butoxycarbonylamino-cyclohexylmethyl ester (Ex. 18 step 1) (400 mg, 1.107 mmol) in dry acetonitrile (4 mL) is then added and the mixture is stirred at room temp for 17 hours. The crude mixture is diluted with water (20 mL) and extracted with EtOAc (3×15 mL). The EtOAc extracts are combined, washed with sat. brine (30 mL), dried (MgSO4), filtered and evaporated to give a mixture of the title compounds as a pale yellow gum. This is used in the next step without further purification.

A crude mixture of step 1 (0.8 g, approx 1.1 mmol) in dry methanol (4 mL) at RT is treated with a solution of 4M HCl in dioxane (4 mL) stirred at RT for 1 hour.

The solvents are evaporated under reduced pressure and the pale yellow gum obtained is placed under high vacuum for 18 hours to ensure complete removal of excess HCl. Due to polar nature of products, no purification is undertaken—crude product is used in the next step without further manipulation or characterisation.

A crude mixture of step 1 (approx. 0.55 mmol of each compound) is suspended in dry DCM (25 mL) at RT. Triethylamine (0.38 mL, 2.75 mmol) is added followed by portionwise addition of 5-chloro-2-methylnicotinoyl chloride (Ex. 17 step 1)(0.274 g, 1.21 mmol). The mixture is stirred at RT for 3 hours and then quenched with water (50 mL) and extracted with EtOAc (3×25 mL). The EtOAc extracts are combined, washed with sat. brine (25 mL), dried (MgSO4), filtered and evaporated to give a pale yellow gum. The compounds are purifified and separated by chromatography on silica gel using ISCO 40 g pre-packed silica column and 0-100% EtOAc in iso-hexane as eluant to afford the title compounds (see Table 12 for characterising data).

The compounds of the following tabulated Examples (Table 9) are prepared by a similar method to that of Example 1 using the appropriate benzamide or pyrazole starting materials (prepared analogously to trans-2-chloro-N-(4-formyl-cyclohexyl)-5-trifluoromethyl-benzamide from trans-4-amino-cyclohexylcarboxylic acid methyl ester hydrochloride and the appropriate benzoly chloride) and the appropriate amine.

The compounds of the following tabulated Examples (Table 10) are prepared according from trans-(4-amino-cyclohexylmethyl)phenylamine (Ex. 5.1 step 5) according to the following general procedure:

A stock solution of trans-(4-amino-cyclohexylmethyl)phenylamine is made up in DMF (1.428 g in 13.6 mL). A stock solution of HATU is made up in DMF (3.808 g in 20.4 mL DMF). Ca. 60 mg PS-DIEA is added to each pre-weighed carboxylic acid. 200 ul Trans-(4-amino-cyclohexylmethyl)phenylamine solution is pipetted into each vial, followed by 300 μl of HATU solution. Vials are sealed and shaken at RT for 16 hr. Crude reactions are purified by loading onto a 1 g SCX-2 cartridge pre-wetted with MeOH, crude is washed with 3 mL MeOH before compounds are eluted with 2×2 mL 2M ammonia in MeOH. Compounds are analysed and evaporated in vacuo. Crude mixtures are purified further by prep HPLC (Waters Sunfire C18 5 micron column, 19×50 mm, mobile phases 0.1% TFA in water, 0.1% TFA in acetonitrile, 6 minute gradient dependant on retention time from analytics). Successful purifications are turned into free-based amines by passing prep fraction through a SCX-2 cartridge pre-wetted with MeOH, washed with 5 mL MeOH, and eluted with 2×2 mL 3.5M ammonia in MeOH. Compounds are evaporated in vacuo.

The compounds of the following tabulated Examples (Table 11), or tautomers thereof, are prepared by a similar method to that of Example 6 by replacing 1-(1H-pyrazol-3-yl)imidazolidin-2-one with the appropriate intermediate.

The compounds of the following tabulated Examples (Table 12), or tautomers thereof, are prepared by a similar method to that of Example 12 using the appropriate acid chloride.