Studies of heterocyclic chemistry. Part 25. Intramolecular cyclisations of N-acylarylethanethioamides leading to thiazoles, 4H-1,3-thiazines, 4H-pyrido[3,2-e]-1,3-thiazines, and 4H-1,3-benzothiazines

Abstract

Thiazoles, 4H-1,3-thiazines, 4H-pyrido[3,2-e]-1,3-thiazines, and 4H-1,3-benzothiazines have been synthesized from N-acyl-(1,3-dithiol-2-ylidene)arylethanethioamides derived from the reactions of 4-aryl-3-halogenoacylthio-4-aryl-3-(2-halogenonicotinoylthio)-, and 4-aryl-3-o-halogenobenzoylthio-3-isothiazoline-5-thiones, respectively, with reactive acetylenes.