Synthesis and characterization of a new zinc(II) complex with tetradentate azo-thioether ligand: X-ray structure, DNA binding study and DFT calculation

A new zinc(II) complex, [Zn(L)(H2O)](ClO4) (1) with azo-thioether containing NSNO donor ligand (HL) was synthesized. The ability of the complex to bind with CT DNA was investigated by UV-vis method and binding constant is found to be 4.16 × 104 M−1. Competitive binding titration with the intercalator ethidium bromide (EB) by fluorescence method was carried to assess the ability of the complex to displace EB from EB-DNA and the Stern-Volmer dynamic quenching constant, Ksv found to be 1.2 × 104 M−1.134