A green approach for the synthesis of biologically active heterocyclic compounds at the platinum electrode

In the present study, 2-amino-5-substituted-1,3,4-oxadiazoles (4a-k) have been synthesized by the electrochemical oxidation of semicarbazone (3a-k) using platinum anode at room temperature under controlled potential electrolysis in an undivided cell assembly. Two platinum electrodes in the form of square plates were used as working as well as counter electrode and saturated calomel electrode was used as reference electrode. The structure of the compounds was confirmed by different techniques i.e. IR, NMR, mass spectral and elemental analyses. The antibacterial activity of the derivatives was also assessed and compared with the parent against a series of Gram-positive Klebsiella pneumoniae, Escherichia coli and Gram-negative bacteria Streptococcus aureus and Bacillus subtilis. The antifungal activity was assessed against the fungal strain Aspergillus niger, Crysosporium pannical, Pellicularia solmanicolor and Candida albicans and compared against the standard antifungal drug Grisevofulvin. All compounds exhibit significant antibacterial activity and antifungal activity.