Syntheses of N-acylhydrazones of 2-hydroxy-3,5-dinitrobenzohydrazide, and their Conversion into 3-Acetyl-2,3-dihydro-1,3,4-oxadiazole

Abstract

N-Acylhydrazones 11-17 were prepared via reaction of 2-hydroxy-3,5-dinitrobenzohydrazide 3 with aromatic aldehydes 4-6 or with aromatic ketone 7 or aliphatic acyclic ketone 8 and cyclic aliphatic ketones 9-10 under reflux in ethanol. Conversion of hydrazide hydrazone 17 into N-acetyl-1,3,4-oxadiazole derivative 19 was achieved via reaction with acetic anhydride 18. The products were characterized by MS, 1H-NMR and 13C-NMR. The structure of 19 was confirmed by X-ray analysis. Compound 19 was evaluated for in vitro antibacterial activity against two microorganisms (S. aureus and E. coli ). The obtained results showed that this compound has good inhibition against the tested bacterial pathogens by micro-dilution method with MIC 15.1 μg.