To a solution of 1-(3-hydroxybenzyl)-5-methoxy-2-phenylindole (108 mg) in N,N-dimethylformamide (1.3 mL) was added potassium carbonate (68.2 mg) at room temperature. Then ethyl bromoacetate (0.047 mL) was added, and the mixture was stirred at room temperature for 3 hours. The reaction mixture was diluted with water and extracted with ethyl acetate. The organic layer was washed with saturated saline, dried over anhydrous sodium sulfate and concentrated under reduced pressure. The residue was purified by silica gel column chromatography (eluting solvent: ethyl acetate-hexane) to obtain the title compound (129 mg).
