To 2.3 g of 2-(aminosulfonyl)benzeneacetic acid methyl ester in 30 ml of acetonitrile was added 1.5 g of anhydrous potassium carbonate and 1.6 g of 4,6-dichloropyrimidin-2-yl isocyanate. The mixture was stirred at room temperature for 6 hours, diluted with 250 g of water and acidified to a pH of about 4. The resulting solid was filtered and dried to yield 1.6 g of methyl 2-[[(4,6-dichloropyrimidin-2-yl)aminocarbonyl]aminosulfonyl]benzeneacetate, a pale yellow solid, m.p. 115°-118° C. It showed infrared absorption peaks at 1730, 1600 and 1560 cm-1 and nuclear magnetic resonance peaks at 3.7 ppm, methyl ester group; 4.2 ppm, benzeneacetic group; 6.9 ppm, pyrimidin H; 7.4-7.6 ppm, aromatic hydrogens; consistent for the product.
