Synthesis and antibacterial screening of S-substituted derivatives of 5-[3,4-methylenedioxyphenyl]-1,3,4-oxadiazol-2-thiol

The most emerging class among the heterocyclic compounds is 1,3,4-oxadiazoles for their diverse biological activities. In the present research work, piperonylic acid [1] was converted consecutively into corresponding ester [2], hydrazide [3] and 1,3,4-oxadiazole [4] through intermolecular cyclization. The synthesized compound 4 was subjected further to S-alkylation/aralkylation, using alkyl/aralkyl halides [5a-m] and S-substituted-1,3,4-oxadiazole derivatives were synthesized [6a-m]. The structure elucidation of the synthesized molecules was processed through [1]H-NMR, IR and mass spectral data. The antibacterial activity showed these molecules moderately good inhibitors of gram-negative and gram-positive bacteria