To a solution of 3,4-dichlorobenzoyl chloride (295 mg, 1.41 mmol) in CH2Cl2 (4 ml) was added a solution of aminopyrrolidinone of Example S (350 mg, 1.41 mmol) and triethylamine (0.4 ml, 2.82 mmol) in CH2Cl2 (4 ml) and the resulting solution was stirred for 18 h at room temperature. Concentration in vacuo gave an oil which was chromatographed on silica gel eluting with 2% EtOH/CH2Cl2 to give the title compound (400 mg, 67%) as a colorless solid. Anal calcd for C20H18N2O4Cl2 : C, 57.02; H, 4.31; N, 6.65. Found: C, 57.05; H, 4.39; N, 6.50. MS M+1 calcd for C20H18N2O4Cl2 422, found 422.
