Synthesis, inhibitory properties on the metabolic enzymes and antioxidant activity of a new series benzimidazole derivatives

Abstract

In this study, a series of new 1, 2-disubstituted benzimidazole was synthesized starting from 5, 6-dichloro-2-(4-methoxybenzyl)-1H-benzimidazole compound which was converted to the ester and hydrazide derivative, respectively. Then, the carbothioamide derivative compounds were obtained by using several isothiocyanates. The thiadiazole derivative compounds were synthesized by closing the intramolecular ring of the carbothioamide derivatives in the presence of conc. H2SO4. And also intramolecular ringing of carbothioamides in basic medium resulted in the formation of the 1,2,4-triazole derivative compounds. Moreover, 5-((5,6-dichloro-2-(4-methoxybenzyl)-1H-benzo[d]imidazol-1-yl)methyl)-1,3,4-oxadiazole-2-thiol compound was syntesized in basic media via reaction of hydrazide derivative with CS2. The treatment of hydrazide derivative with various salicylic aldehydes gave Schiff-based benzimidazole derivative compounds. The structural characterization of all synthesized compounds was elucidated by elemental analyses, 1H NMR, 13C NMR and mass spectral methods. They were also screened for their antioxidant activity and inhibitory properties on the metabolic enzymes such as urease and xanthine oxidase.