To a solution of the [6-[(4-chlorophenylsulfonyl) (2,5-difluorophenyl)methyl]pyridin-3-yl]methylamine (41 mg, 0.10 mmol) obtained in Example 351, (E)-3-(pyridin-4-yl)acrylic acid (15 mg, 0.10 mmol), benzotriazol-1-ol (14 mg, 0.10 mmol), and N-methylmorpholine (0.011 ml, 0.10 mmol) in dichloromethane (1 ml) was added 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride (19 mg, 0.10 mmol) at 0° C. The resulting mixture was stirred at room temperature for 19 hours. The reaction mixture was washed with a saturated aqueous solution of sodium bicarbonate. The organic layer thus obtained was dried over anhydrous sodium sulfate and then filtered. The filtrate was concentrated under reduced pressure. The residue was subjected to flash silica gel chromatography and a fraction obtained from the elution portion with ethyl acetate was concentrated under reduced pressure. The solid thus obtained was washed with diethyl ether and then collected by filtration, whereby the title compound (35 mg, 0.065 mmol, 65%) was obtained as a white solid.
