Synthesis, spectroscopic characterization, antimicrobial, DNA binding and oxidative-induced DNA cleavage activities: New oxovanadium(IV) complexes of 2-(2-hydroxybenzylideneamino)isoindoline-1,3-dione

A mononuclear complex [(phen)VO(bid)]SO4·3H2O (1), (phen = 1,10-phenanthroline) and a binuclear [(VObid)2]·H2O (2), with Hbid [(E)-2-(2-hydroxybenzylideneamino)isoindoline-1,3-dione] were prepared and characterized by elemental analysis, IR, mass, UV–Vis spectral studies, ESR, molar conductance and thermogravimetric analysis. The DNA-binding properties of the complexes 1 and 2 were investigated by UV–spectroscopy, fluorescence spectroscopy and viscosity measurements. The superoxide dismutase-like activity of the complexes has been determined. The spectral results suggest that the complexes 1 and 2 can bind to DNA by intercalation. The cleavage properties of these complexes with super coiled pUC19 have been studied using the gel electrophoresis method, where both complexes 1 and 2 displayed chemical nuclease activity in the absence and presence of H2O2via an oxidative mechanism. All the complexes inhibit the growth of both Gram positive and Gram negative bacteria to competent level. Minimum inhibitory concentration (MIC) was determined by microtiter method.

Graphical abstractTwo new oxovanadium(IV) complexes were synthesized in different ratio with the Schiff base Hbid and heterocyclic base phen. Their biological efficacy as antimicrobial agent as well as DNA binding and DNA cleavage activity was carried out.Figure optionsDownload full-size imageDownload as PowerPoint slideHighlights► Synthesis of new Schiff base oxovanadium(IV) complexes. ► Spectral and thermal characterization of the synthesized compounds. ► SOD activity. ► Antimicrobial activity of the synthesized complexes. ► DNA binding properties and oxidative induced supercoiled DNA cleavages of the complexes.