反应详情

4.76 g (35.3 mmol) of 1-hydroxybenzotriazole and 7.27 g (35.3 mmol) of dicyclohexylcarbodiimide were added to a solution of 7.02 g (29.4 mmol) of 4-(4-methylsulfonylaminophenyl)-4-oxobutyric acid in 60 ml of dimethylformamide at 0° C. and the mixture was stirred at that temperature for 1 h. 4.80 g (35.3 mmol) of 2-(6-methyl-2-pyridyl)ethylamine obtained in the above step (2) was added thereto. The mixture was stirred at room temperature for 12 h and then filtered. The filtrate was concentrated. The solid residue thus obtained was washed with a solvent mixture of chloroform/acetic acid/ethanol to give 9.39 g (yield: 89%) of the intended compound in the form of white crystals.