To a solution of tert-butyl 4-(4-(5-(3-(4-cyanophenyl)azetidine-1-carbonyl)-2-methylphenyl)-5-methyl-1H-imidazol-2-yl)piperidine-1-carboxylate (compound 182.3, 475 mg, 0.88 mmol) in 20 mL DCM, was added trifluoroacetic acid (4 mL). The reaction was stirred for 1.5 hours, concentrated under reduced pressure and neutralized with 10 mL Na2CO3 (1M) to obtain a crude product after lyophilization. A mixture of 4-(1-(4-methyl-3-(4-methyl-2-(piperidin-4-yl)-1H-imidazol-5-yl)benzoyl)azetidin-3-yl)benzonitrile (252 mg, 0.57 mmol), acetic anhydride (71 μL, 0.75 mmol) and triethylamine (120 μL, 0.86 mmol) was stirred at room temperature for 16 hours. The reaction was concentrated under reduced pressure, then diluted with saturated NaH2PO4 (20 mL) and extracted with EtOAc (3×20 mL). The organic phase was dried over MgSO4 and concentrated under reduced pressure. The residue was purified by preparative TLC with 10% methanol in dichloromethane and lyophilized to give 235 mg (80%-2 steps) of the title compound as a white solid. m/z (ES+) 482 (M+H)+.
