Microwave assisted synthesis of N-substituted benzylidene-2-(1H-benzotriazol-1-yl) acetohydrazide derivatives as antibacterial agents
Abstract
Benzotriazole is an important class of heterocyclic compounds which possesses good antibacterial activity, oral bioavailability and low toxicity. All these properties have urged us to synthesize a wide range of novel chemotherapeutics with benzotriazole as main nucleus. The reaction of o-phenylenediamine with glacial acetic acid resulted in the formation of benzotriazole, which was further reacted with ethylchloroacetate and potassium carbonate solution in acetone to formethyl-2-(1H-benzo[1, 2, 3]triazole-1-yl)acetate. Ethyl-2-(1H-benzo[1, 2, 3] triazole-1-yl)acetate when reacted with hydrazine hydrate in the presence of ethanol, gave (benzotriazol-1-yl)acetic acid hydrazide. Finally, the resulted hydrazide produced was condensed with aromatic aldehydes in the presence of ethanol and glacial acetic acid under microwave conditions to give Schiff ‘s bases (six compounds 5a-5f). The TLC was used as a method for purity determination and characterization of synthesized compounds was done using IR and 1HNMR. The in vitro antibacterial activity of synthesized compounds was evaluated using Gram positive and Gram-negative strains (E. coli, S.aureus and B. substilis, P. aeruginosa) by cup and plate method. All the synthesized compounds showed activity against the above-mentioned microbes. Compounds 5b, 5d, 5e were found to possess maximum antibacterial activity as compared to the standard vancomycin.
Keywords
Benzotriazole, Schiff ‘s bases and Antibacterial agents