150 mg (0.50 mmol) of 4-(4-chlorobenzoyl)-1,3,4,5-tetrahydrobenzo[e][1,4]diazepin-2-on was dissolved in 10 ml of DMF. 24 mg (0.60 mmol) of sodium hydride was added to the obtained solution, and they were stirred at room temperature for 30 minutes. 160 mg (0.70 mmol) of methyl 3-(bromomethyl)benzoate was added to the reaction mixture, and they were stirred at room temperature overnight. After the treatment with ethyl acetate as the extracting solvent by an ordinary method, the obtained crude product was purified by the silica gel column chromatography.
