4-(4-Hydroxyphenyl)-7-[1-(tert-butoxycarbonyl)-5-(piperidinomethyl)indol-2-yl]isoindolinone (56.2 mg, 0.105 mmol) was dissolved in N,N-dimethylacetoamide (3.9 mL), and the solution was added with sulfamoyl chloride (61 mg, 0.53 mmol), followed by stirring at room temperature for 17 hours. The reaction mixture was added with water and extracted with ethyl acetate and chloroform. The organic layer was washed with saturated brine and dried over anhydrous sodium sulfate. The solvent was evaporated under reduced pressure and the residue was purified by preparative thin-layer chromatography (chloroform/methanol=5/1) to obtain 4-(4-sulfamoyloxyphenyl)-7-[1-(tert-butoxycarbonyl)-5-(piperidinomethyl)indol-2-yl]isoindolinone (36.2 mg, yield 56%).
