0.75 g (2.5 mmol) of (2-([4-chloro-2-(methoxycarbonyl)phenyl]amino)-2-oxoethoxy)acetic acid, 0.43 g (2.5 mmol) of 4-(pyridin-4-yl)aniline, 0.58 g (3.0 mmol) of 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride, 0.41 g (3.0 mmol) of 1-hydroxybenzotriazole were stirred in 5.3 mL of DMA for 2 hours. After completion of the reaction, the reaction solution was introduced into an aqueous sodium bicarbonate solution. The solid was separated by filtration, and washed with water to give 0.96 g of 5-chloro-2-([(2-oxo-2-([4-(pyridin-4-yl)phenyl]amino)ethoxy)acetyl]amino)benzoic acid.methyl ester (yield: 85%).
