Synthesis and pharmacological study of thiazolidinones and mannich bases of 4-amino-3-mercapto-5- pyridin-3’-yl-[1,2,4]- triazole

Abstract

4-Amino-5-(3-pyridyl)-4H-1,2,4-triazole-3-thiol 1 is prepared from methyl nicotinate through a multi-step reaction sequence1. Compound 1 react with various aromatic aldehydes in the presence of gl. acetic acid to give 4-substituted-benzal-amino-3-mercapto-5-pyridin-3’yl-[1,2,4]-triazoles 2a-i, which on further cyclo-condensation with thioacetic acid afforded 3-(3’-mercapto-5’-pyridin-3’’-yl-[1, 2, 4]-triazole-4’-yl)-2-aryl-1, 3-thiazolidin-4-ones 3a-i. Compounds 2a-i on reaction with formaldehyde and with different aromatic amines in dioxane yielded 2-[bis-aryl-amino-methyl]-5-pyridin-3’-yl-4-substituted-banzal-amino-2,3-di¬¬¬hydro-[1,2,4]-triazlole-3-thiones 4a-i. The pharmacological evaluations have been performed for their antimicrobial and antitubercular activities.