SYNTHESIS, CHARACTERIZATION AND EVALUATION OF ANTIMICROBIAL ACTIVITIES AND CYTOTOXICITY OF SOME NEW 1,2,4-TRIAZOLE DERIVATIVES CONTAINING 2-SUBSTITUTED BENZIMIDAZOLE

Abstract

The development of a potent new drug with high biological activity is a challenge in drug design and is of strategic importance. Due to the increasing resistance of pathogens on the existing drugs there is always a need for the development of a potent drug with high biological activity. The pharmacological effects are seen in compounds with the presence of different moieties of pharmaceutical importance such as triazole, Schiff’s base, benzimidazole as described in the chemical literature. By applying different synthetic reactions in a convergent pattern, two new compounds have been prepared with three pharmacophores viz. triazole, benzimidazole and Schiff base incorporated in a single compound. The structure of the prepared compounds was confirmed by different spectroscopic techniques like, FT-IR, UV-VIS, 1H-NMR, and 13C-NMR. The progress of the reaction was monitored by TLC and determination of melting point. All compounds exhibited moderate antibacterial activity against Staphylococcus aureus (ATCC 6538P) and Staphylococcus epidermidis (ATCC 1228). Antioxidant activity was carried out by DPPH radical scavenging test and among the tested five compounds, the IC50 value of 4-amino-2- (2-hydroxyphenyl)-1H-1,2,4-triazole-5-thione was found to be 32.364 μgmL-1 which is closer to the ascorbic acid sample that was found to be 28.546 μgmL-1. All tested compounds were toxic against brine shrimp where 5-((1H-benzo[d]imidazol-2-yl)thio)-4-((4- chlorobenzylidene) amino)-4H-1,2,4-triazol-3-yl) (2-hydroxyphenyl) methanone was comparatively more toxic (LC50= 26.827 μgmL-1)