To a mixture of (E)-3-[6-(6-methoxy-2-phenyl-1H-indol-3-ylmethyl)pyridin-2-yl]acrylonitrile (67 mg), isopropyl alcohol (1.5 mL) and water (0.5 mL) were added sodium azide (59.6 mg) and zinc bromide (51.6 mg), and the mixture was heated under reflux for 32 hours. Then isopropyl alcohol (1.5 mL) and water (0.5 mL) were added thereto, followed by heating under reflux for 62 hours. The reaction mixture was left to be cooled, diluted with 1 mol/L hydrochloric acid, and then stirred for 5 minutes. To the mixture was added water, followed by extraction with ethyl acetate. The organic layer was washed with water, dried over anhydrous magnesium sulfate, and then concentrated under reduced pressure. The residue was purified by silica gel column chromatography (eluting solvent: ethyl acetate-hexane) to obtain the title compound (25.8 mg). 1H-NMR (DMSO-d6) δ ppm: 3.77 (3H, s), 4.34 (2H, s), 6.65 (1H, dd, J=2.3, 8.5 Hz), 6.87 (1H, d, J=2.3 Hz), 7.16-7.23 (1H, m), 7.32-7.43 (2H, m), 7.46-7.54 (3H, m), 7.65-7.85 (5H, m), 11.16 (1H, s). ESI-MS (m/z): 409 (M+H)+
