Synthesis and antimicrobial testing of thiazolinyl-, thiazolidinonyl-quinoxalines and 1,2,4-triazolo[4,3-a]quinoxalines

Three novel series of quinoxaline derivatives namely 1-substituted amino-4-phenyl-1,2,4-triazolo[4,3-a]quinoxalines 3a-c, 2-[3,4,5-trisubstituted-2,3-dihydrothiazol-2-ylidene)hydrazono]-3-phenylquinoxalines 4a-j, 5a-e, and 2-[(3-substituted-4-oxothiazolidin-2-ylidene)hydrazono]-3- 6a-e have been synthesized by cyclization of the key intermediates 2-substituted thiocarbamoylhydrazino-3-phenylquinoxalines 2a-e. The prepared compounds were tested in vitro for their antimicrobial activity.