Synthesis, Characterization and Antimicrobial Activity of Novel 3,5-Disubstituted-1,3,4-oxadiazole-2-ones

A series of novel 5-(3,4-dichlorophenyl)-3-[(4-substitutedpiperazino)methyl]-1,3,4-oxadiazole-2(3H)-one have been synthesized starting from 3,4-dichlorobenzoic acid. Structure identification of the compounds was done by IR, H-1-NMR, C-13-NMR spectra and elemental analyses. The compounds were screened in vitro for their antimicrobial activity against Aspergillus sp., Fusarium oxysporum, Botrytis cinerea, Penicillium sp., Bacillus megaterium, Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa by disc-diffusion method. According to the activity studies, all compounds possess selective antifungal effect. Among the synthesized compounds, 5a-5d, 5h, 5j and 5p were found to be the most effective derivatives with higher zone inhibition values than standard drug nystatin against variable fungal species.