SYNTHESIS OF NOVEL HETEROCYCLES FROM 2-AMINO-3-(CYANOMETHYLSULFONYL)THIOPHENE

The synthesis and selected reactions of 2-amino-3-(cyanomethylsulfonyl )thiophene is reported. In particular, cyclization reaction of the ver satile aminothiophene yielded a number of novel thieno[3,2-b][1,4]-thi azine 1,1-dioxides, as well as the analogous thieno[2,3-e][1,3,4]thiad iazine 4,4-dioxide. Reaction of the thienothiazine system with hydrazi ne was subsequently explored, which resulted in either ring-opening of the thiazine and formation of an aminopyrazole or solely ring cleavag e depending on the thiazine substituent. Additionally, the synthesis o f bis(2-amino-3-thienyl)sulfone and the corresponding bis-acetamide is described.