2-Aminothiazole → 4-hydroxy-2-methyl-N-(2-thiazolyl)-2H-thieno[3,4-e]-1,2-thiazine-3-carboxamide 1,1-dioxide

Participants

Reaction Steps

0.9 G. of 4-hydroxy-3-methoxycarbonyl-2-methyl-2H-thieno[3,4-e]-1,2-thiazine 1,1-dioxide are suspended together with 0.4 g. of 2-aminothiazole in 100 ml. of absolute xylene and heated to reflux for 4 hours, 70 ml. of xylene being slowly distilled off. A crystalline precipitate separates from the cooled solution and is filtered off under suction. There is obtained 4-hydroxy-2-methyl-N-(2-thiazolyl)-2H-thieno[3,4-e]-1,2-thiazine-3-carboxamide 1,1-dioxide of melting point 243°-245° C. (decomposition).

Provenance & Evidence