Synthesis and investigation of antibacterial activity of 1-(4-substituted phenyl)-5-oxopyrrolidine-3-carbohydrazide derivatives

Hydrazides are very important precursors for the synthesis of a wide variety of derivatives, including heterocyclic compounds of biological interest in drug design and discovery. Acid hydrazides with a pyrrole, thiophene, furan, quinoline, isoquinoline, isoxazole and benzimidazole core in the structure were found to be used in medicine, pharmacy, agriculture and many other fields. In the search for compounds with antibacterial properties, mono- and dihydrazides were used in this study to prepare 1-(4-substituted phenyl)-5-oxopyr-rolidine-3-carbohydrazide derivatives bearing the corresponding hydrazone and azole substituents. The formation of the target compounds was performed via condensation reactions with the chosen aromatic aldehydes and isatin, which led to the construction of the appropriate hydrazone-type structures as well as with diketones which afforded compounds with pyrazole and pyrrole nuclei. In addition, a preliminary antibacterial evaluation of the synthesised compounds was performed using the gram-positive Bacillus subtilis and the gramnegative Escherichia coli bacterial strains. As it was expected, the evaluation revealed potential antibacterial candidates that can help address the global challenges of antibiotic resistance and infectious disease outbreaks.