Novel Three Component Synthesis of 1,2,4-Triazolo[3,4-b]thiazoles and Their Antimicrobial Activity.

1,2,4-Triazolo[3,4-b]thiazole derivatives 5a-j have been synthesized by novel multi-component reaction of 2,4-dichloro-5-fluorophenacyl bromide ( 1 ), thiosemicarbazide ( 2 ), and aromatic carboxylic acids ( 4 ) using phosphorous oxychloride as the cyclizing agent. This reaction protocol is simple, efficient, and requires shorter reaction times in comparison to the conventional multi-step synthesis. The products were identified to be same by an alternate synthesis. All the compounds were screened for their antimicrobial activity against some of bacterial and fungal strains. [ABSTRACT FROM AUTHOR]