PURPOSE: 1-Substituted imidazole-4, 5-dicarboxylic acid id heated in acetic anhydride to produce title compound useful as intermediate of agricultural chemicals, drugs, dyes, and curing agents in high yield.

CONSTITUTION: A 1-substituted imidazole-4, 5-dicarboxylic acid of formula I (R1 is 1-4C alkyl, 7-10C aralkyl) as 1-methylimidazole-4,5-dicarboxylic acid is heated in acetic anhydride at 80-140, preferably about 100W110°C, to form a 1-substituted imidazole-5-carboxylic acid of formula II as 1-methylimidazole-5-carboxylic acid, which is heated with thionyl chloride. After the excess of thionyl chloride is distilled off, the product is reacted with an amine of the formula: R2R3NH(R2, R3 is H, alkyl, phenyl) by heating to form the 1-substituted imidazole-5-caroxylic acid amide derivative of formula III as 1-methylimidazole-5-caroanilide.