Synthesis, characterization, computational study, and screening of novel 1-phenyl-4-(2-phenylacetyl)-thiosemicarbazide derivatives for their antioxidant and antimicrobial activities

Abstract

Condensation reaction of phenyl acetyl isothiocyanate (1) and phenyl hydrazine was performed to obtain 1-phenyl-4-(2-phenylacetyl) thiosemicarbazide (2). Compound (2) was utilized as starting material for synthesis of different fused 1,2,4-triazole compounds. Reaction of (2) with hydrazine hydrate, anthranilic acid and ethyl glycinate under microwave irradiation and traditional thermal conditions afforded 1,2,4-traizol derivatives (4, 5 and 6) respectively. On the other hand, cyclization reaction of compound (2) under microwave irradiation gave 1,2,4-triazole-3-thione derivative (3). The microwave assessed reaction produced higher yield reaction and purity than the traditional thermal reaction. The chemical structures of the synthesized compounds were elucidated using elemental analysis, FTIR, 1H NMR, and GC/MS spectroscopy. The synthesized compounds (2–7) were evaluated for their antimicrobial and antioxidant potentials. Density functional theory (DFT) was evaluated at B3LYP/3-21G level to study the electronic and geometric characteristics of (4–6) compounds including the optimized structures, relative binding energies, atomic charges, position of HOMO and LUMO of the molecules.