Depending on the reagent ratio, 5-dimethylaminomethyl-4-imidazole-4-carboxylic acid and 2,4,5-tris(dimethylaminomethyl)imidazole were obtained in the aminomethylation of imidazole-4-carboxylic and imidazole-4,5-dicarboxylic acids. The oxidation of these compounds with nitric acid leads to imidazole-4,5-dicarboxylic acid.