Dioxidomolybdenum(VI) complexes of azo-hydrazones: Structural investigation, DNA binding and cytotoxicity studies

[Display omitted] The synthesis of three new dioxidomolybdenum(VI) complexes [MoO2L1-3(X)] (1–3) {where X = EtOH for 1 and 3 and DMSO for 2} of aroylhydrazone ligands (H2L1-3) containing azobenzene moiety have been reported. H2L1-3 has been synthesized from the condensation of 5-(arylazo) salicylaldehyde derivatives with corresponding aroyl hydrazides. The azobenzene functionality was incorporated in the aroylhydrazone systems containing benzoyl, naphthyl and furyl moieties in order to explore their influence if any, on the biological properties of the corresponding molybdenum complexes. All the synthesized ligands and metal complexes were successfully characterized by elemental analysis, IR, UV–vis, NMR spectroscopy and HRMS. Redox properties of the complexes were studied by cyclic voltammetry. Molecular structures of 1–3 have been determined by X-ray crystallography. The electronic spectra of the complexes have been further analysed using time dependent density functional theory (TDDFT). DNA binding studies reveal that the complexes interact with calf-thymus DNA (CT-DNA) with binding constants in the range 104 M−1. The cytotoxicity activity of the complexes against A549 and HCT-15 cell lines has also been explored.