To a solution of 5-(3-formylphenyl)-3-(1-{[2-(methyloxy)ethyl]sulfonyl}-4-piperidinyl)-1H-indole-7-carboxamide (25 mg, 0.053 mmol) in MeOH/CH2Cl2 (1 mL/1 mL) was added methyl amine (0.15 mL, 0.33 mmol). The reaction mixture was stirred at room temperature for 2 hours before NaBH4 (13.2 mg, 0.33 mmol) was added. The reaction mixture was stirred at room temperature overnight and evaporated all the solvent. The residue was purified by using a Gilson semi-preparative HPLC system, eluting with 10% B to 80% B, where A=H2O (0.1% trifluoroacetic acid) and B=CH3CN (0.1% trifluoroacetic acid) pumped at 25 mL/min to give the title compound (10.0 mg, 39%).
