Synthesis and biological evaluation of 3-benzyl/piperazino- methyl-1,2,3-triazol-4-yl)-2,3-dihydro-1,3,4-thiadiazole-2-thione

A new series of 3-benzyl-1,2,3-triazol-4-yl)-2,3-dihydro-1,3,4-thiadiazole-2-thione 8(a-d) and 3- piperazinomethyl-1,2,3-triazol-4-yl)-2,3-dihydro-1,3,4-thiadiazole-2-thione 9(a-e) has been synthesized from 5-(5-methyl-1-phenyl-1H-1,2,3-triazol-4-yl)-2,3-dihydro-1,3-thiazole-2-thione 7 . Chemical structures of all the new compounds were established by IR, 1H, 13C NMR, MS and elemental data. The compounds 8(a-d) and 9(a-e) were evaluated for their antibacterial activity against human pathogenic organisms Escherichia coli, Bacillus subtilis and Staphylococcus typhi. The investigation of antibacterial screening data reveal that, compounds in the series of 8 which contain 4-chlorobenzyl, 4-nitrobenzyl moiety on the thiadiazole and compounds in series of 9 containing N-methylpiperazine moiety on the thiadiazole, displayed good antibacterial activity against all the organisms. Compounds 8c and 9a were highly active against B. subtilis and S. typhi. Most of these new compounds showed appreciable activity against test bacteria and emerged as potential molecules for further development.