To a solution of N-{3-[5-(1-piperidin-4-yl-1H-pyrazol-4-yl)-1H-benzimidazol-1-yl]phenyl}-N′-(2,2,2-trifluoroethyl)urea HCl salt (20.0 mg, 0.0414 mmol) in 1,2-dichloroethane (2 mL) and ethanol (0.5 mL) was added cyclopropanecarboxaldehyde (4.6 μL, 0.062 mmol) and triethylamine (17 μL, 0.12 mmol). The suspension was stirred at r.t. for 1 h then sodium triacetoxyborohydride (18 mg, 0.083 mmol) was added. The reaction solution was stirred at r.t. overnight. The reaction solution was concentrated under reduced pressure to dryness. The residue was dissolved in MeOH, and purified by RP-HPLC (pH=10) to afford the desired compound. LCMS (M+H)+: m/z=538.2.
