Ethyl 7-(benzyloxy)-5-[4-(methylsulfonyl)phenoxy]-1H-indole-2-carboxylate (0.40 g) was dissolved in a tetrahydrofuran (5 mL)-ethanol (5 mL) mixed solvent, 10% palladium-carbon (containing water (50%), 0.80 g) was added, and the mixture was stirred under a hydrogen atmosphere at room temperature for 4 hr. The reaction mixture was filtered, and the filtrate was concentrated under reduced pressure. The residue was crystallized from diethyl ether and the obtained solid was washed with a diethyl ether-hexane mixed solvent to give the title compound (0.31 g, yield 96%) as a pale-yellow solid. The pale-yellow solid was recrystallized from ethanol-hexane to give pale-yellow crystals.
