Synthesis and antioxidant capacities of some new benzimidazole derivatives.

In this study, we prepared some new oxadiazolyl benzimidazole derivatives and investigated their antioxidant properties by determination of microsomal NADPH-dependent inhibition of lipid peroxidation levels (LP assay) and microsomal ethoxyresorufin O-deethylase activity (EROD assay). Some of these compounds 20, 23 had slightly inhibitory effects (28%) on the lipid peroxidation levels at 10(-3 )M concentration lower than standard BHT (65%). 5-[2-(Phenyl)-benzimidazol-1-yl-methyl]-2-mercapto-[1,3,4]-oxadiazole 16 was found to be more active than caffeine on the ethoxyresorufin O-deethylase activity with an IC(50 )value of 2.0 6 10(-4 )M.