A solution of 0.800 g of N-(2-pyridylmethyl)-4-acetylamino-3-aminobenzamide in 10 ml of methanol were added 1.08 g of 4-(4-bromomethylphenyl)-1,2,3-thiadiazole and 0.710 g of sodium hydrogencarbonate, and the mixture was stirred at 70° C. for 1 hour. The reaction solution was concentrated, and was purified through silica-gel column chromatography (eluent: a mixture of ethyl acetate and methanol at a ratio of 9:1) to give 0.830 g of N-(2-pyridylmethyl)-4-acetylamino-3-[4-(1,2,3-thiadiazol-4-yl)benzylamino]benzamide
