Synthesis, Characterization and Biological Studies of Porphyrinyloxovanadium(IV)benzimidazole Complexes

Abstract

The six-coordinate oxovanadium(IV) complexes [VO(RTPP)(L)] (where R=H, methyl, methoxy and chloro groups and L= methyl and ethyl substituted benzimidazoles) were prepared by reacting the ligands; 2-methylbenzimidazole and 2-ethylbenzimidazole with various VO(RTPP). The complexes were characterized by elemental analysis, IR, UV-Vis and 1 H & 13 C NMR. All complexes show V=O stretching vibrations between 932 and 1050 cm −1 . The presence of three d-d transitions occurring between 400 and 625 nm confirm the d 1 electronic configuration of the complexes. Based on spectral and magnetic studies, an octahedral geometry is assigned for all the complexes. The electrochemical behavior of some complexes was also investigated using cyclic voltammetry. The complexes exhibit positive antibacterial activities but showed negative antifungal activity. The free-radical-scavenging ability of the metal complexes was also determined by their interaction with the stable free radical 2,2-diphenyl-1-picrylhydrazyl, which showed encouraging antioxidant activities.