Synthesis, Characterization and Theoretical Calculations Of Schiff Base Derived From 3-Amino-1,2,4-Triazole-5-Thiol As Potent Antimicrobial Agent

Abstract

Schiff bases are important chemical compounds in various fields such as inorganic, analytical and medicinal chemistry due to their versatilities. Schiff bases are formed by the condensation of aldehydes or ketones with primer amines. Their active group called azomethine (CH=N) or imine (C=N) makes them ideal candidates for developing new drugs. They can form numerous stable complexes when they are coordinated with different transition metal ions. Thus, metal complexes of Schiff bases have been studied extensively due to their various applications and chemical activities. And also, the compounds containing triazole derivatives possess chemotherapeutic effects including antibacterial activities against drug-sensitive as well as drug-resistant pathogens. 1,2,4-triazoles are a very important class of compounds that have attracted the attention of many scientists in medical and pharmaceutical fields due to their various biological activities such as anticancer, antimicrobial, anticonvulsant.

 In this study, we synthesized Schiff base derived from 3-amino-1,2,4-triazole-5-thiol (ATT) and 5-chlorosalicylaldehyde (5ClSA), and characterized using spectroscopic method. In theoretical studies, the molecular structure of Schiff base was optimized using the density functional theory (DFT) with B3LYP/6-31+G (d,p) level of theory. In addition, the frontier molecular orbitals (FMOs:HOMO and LUMO) and the molecular electrostatic potential (MEP) map were performed by the same basis set using Gaussian 09 software.  The global reactivity descriptors  such as electronegativity (χ), hardness (ղ), softness (S), chemical potential (µ) and electrophilicity (ω) were also calculated by using HOMO and LUMO energies.