GREEN AQUEOUS SYNTHESIS AND ANTIMICROBIAL EVALUATION OF 3,5-DISUBSTITUTED 1,2,4-TRIAZOLES

Abstract

An eco-friendly and simple procedure was proposed for the synthesis of 3,5-disubstituted 1,2,4-triazoles by optimized reaction of benzamidine hydrochloride and various aryl hydrazides. H₂O and K₂CO₃ were applied as green and available solvent and base, respectively. The products were generated in good to high yields in one step and sufficient purity after a simple workup. The designed process is applicable to other organic syntheses especially from poorly water-soluble reactants such as hydrazines or hydrazides. Inhibitory activity of all prepared derivatives was evaluated against 10 pathogenic bacteria strains including both Gram-positive and Gram-negative, as well as 2 mold and 1 yeast strains. The prepared derivatives showed good antimicrobial activities. 1,2,4-Triazoles containing 2-hydroxynaphthalen-3-yl and 5-chlorothiophen-2-yl substituents at position 3 showed the best antifungal and antibacterial properties, respectively.