A mixture of 30 mg (0.074 mmol) of N-[2-(4-aminophenyl)-1,1-dimethylethyl]-N′-[3-methoxy-4-(5-oxazolyl)phenyl]oxalamide, 10 mg (0.082 mmol) of benzoic acid, 14 mg (0.092 mmol) of 1-hydroxybenzotriazole hydrate, 21 mg (0.11 mmol) of 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride and 18 mg (0.16 mmol) of N-ethylmorpholine in 2 ml of dichloromethane was stirred at room temperature for 18 hours then diluted with dichloromethane and washed with 2M hydrochloric acid and saturated sodium bicarbonate. The organic phase was dried over magnesium sulphate, evaporated to dryness and the residue chromatographed on silica gel using ethyl acetate/petrol (2:1) for the elution. There was obtained 9 mg of N-[2-(4-benzamidophenyl)-1,1-dimethylethyl]-N′-[3-methoxy-4-(5-oxazolyl)phenyl]oxalamide as a white solid. MS: m/e 513 [M+H]+.
