Synthesis and evaluation of in vitro antioxidant capacities of some benzimidazole derivatives

New, except Id, melatonin analogue benzimidazole derivatives were synthesized and characterized in the present study. The potential role of melatonin as an antioxidant by scavenging and detoxifying ROS raised the possibility that compounds that are analogous to melatonin can also be used for their antioxidant properties. Therefore the antioxidant effects of the newly synthesized compounds were investigated in vitro by means of their inhibitory effect on hydrogen peroxide-induced erythrocyte membrane lipid peroxidation (EMLP) and on various erythrocyte antioxidant enzymes viz. superoxide dismutase (SOD), catalase (CAT) and glucose-6-phosphate dehydrogenase (G6PD). The synthesized benzimidazole derivatives showed remarkable antioxidant activity in vitro in the H2O2-induced EMLP system. Furthermore their effects on various antioxidant enzymes are discussed and evaluated from the perspective of structure-activity relationships

Effects of 2-arylbenzimidazoles on rat hepatic microsomal monooxygenase system

1. The effects of eight newly synthesized 2-aryl substituted benzimidazole derivatives on control and phenobarbital (PB) treated rat liver microsomal aniline 4-hydroxylase and ethylmorphine N-demethylase activities, and their binding to control and PB-treated rat liver microsomal oxidized cytochrome P-450 are presented. 2. All compounds inhibited ethylmorphine N-demethylase activity with I50 values ranging from 8.50 × 10−4 M to 27.83 × 10−4 M in control and ranging from 2.80 × 10−4 M to 15.79 × 10−4 M in PB-treated rats. 3. Aniline 4-hydroxylase activity was inhibited by all of the compounds tested having I50 values in the range of 7.04 × 10−4 M-31.37 × 10−4 M in PB-treated rats, but only five of the compounds showed inhibitory activity in control rats. 4. Only a few significant regression coefficients could be found between the parameters of the chemicals studied and their inhibitory patterns. 5. No correlation has been observed between the binding of the derivatives and their inhibitory pattern.Publisher's Versio