ANTIOXIDANT POTENTIAL AND ANTIMICROBIAL SCREENING OF SOME NOVEL IMIDAZOLE DERIVATIVES

Abstract

Bioactive novel imidazole derivatives have been synthesized under solvent free condition using molecular iodine as the catalyst and they are characterized by NMR spectra, X - ray, mass and CHN analysis. Their antioxidant potential were evaluated using different in vitro antioxidant models namely, DPPH (1,1 diphenyl - 2 - picryl hydroxyl) radical, s uperoxide anion and hydroxyl radical scavenging activities. The p - tolyl ring at C - 3 and p - fluorophenyl at C - 2 of the imidazole ring has maximum OH • (fpdmti) when compared with other imidazole derivatives. The low IC 50 value may be due to the electron donat ing (+I effect) ability exerted by the methyl substituent and electron withdrawing ( - I effect) ability exerted by the fluoro substituent. The 3,5 - dimethylphenyl ring at C - 2 of the imidazole ring (dmmppi) has maximum DPPH • and superoxide anion radical scave nging activities when compared with other imidazole derivatives and the low IC 50 value of dmmppi) may be due to the electron donating (+I effect) ability exerted by the two methyl substituent’s. Their antibacterial screening against Staphylococcus aureus , Escherichia coli and Klbesiella pneumoniae and antifungal activity against Aspergillus Niger, Aspergillus flavus and Candida - 6 were also evaluated.