PROCESS FOR THE PREPARATION OF METHYL-4-(4,5-DIHYDRO-3-METHOXY-4-METHYL-5-OXO-1H-1,2,4-TRIAZOLE-1-YL)CARBONYL)SULPHAMOYL-5-METHYLTHIOPHENE-3-CARBOXYLATE

摘要

The invention relates to a method for preparing methyl 4-[(4,5-dihydro-3-methoxy-4-methyl-5-oxo-1H-1,2,4-triazol-1-yl)carbonyl)sulfamoyl]-5-methylthiophene-3-carboxylate from 4-methoxycarbonyl-2-methylthiophene-3-sulfonyl chloride in the presence of an imidazole base substituted in the 1-position or in the presence of a mixture of bases comprising an imidazole base substituted in the 1-position (N-alkylimidazole).