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

Participants

Reaction Steps

0.25 g. of 4-hydroxy-2-methyl-3-methoxycarbonyl-2H-thieno[3,2-e]1,2-thiazine-1,1-dioxide is heated under reflux for 17 hours with 0.14 g. of 2-aminothiazole in 28 ml. of absolute xylene, while passing a stream of nitrogen through the said mixture. The mixture is cooled to room temperature and crystallization of the product is initiated by scratching. The product is kept overnight in the cold. The precipitate crystals are removed by filtration under suction and recrystallized from ethanol, whereby 4-hydroxy-2-methyl-3-(2-thiazolylcarbamoyl)-2H-thieno[3,2-e]1,2-thiazine-1,1-dioxide having a melting point of 226°-227° (with decomposition) is obtained.

Provenance & Evidence