Synthesis and Characterization of Ni(II)/Zn(II) Metal Complexes Derived from Schiff Base and Ortho-Phenylenediamine: In vitro DNA Binding, Molecular Modeling and RBC Hemolysis

Abstract

Herein, we report the synthesis and characterization of [Ni(L)(o–phenyl)]Cl (1) and [Zn(L)(o–phenyl)]Cl (2) new metal complexes derived from Schiff base ligand of 2–ethoxy–6–((pyrazin–2–ylimino)methyl)phenol (L) and ortho-phenylenediamine. The biophysical studies of ligand and complexes 1 and 2 have been investigated with CT DNA and experimental outcomes show that both the complexes exhibited higher binding propensity towards DNA as compared to ligand L. Furthermore, molecular docking studies confirmed that both the complexes preferentially bind in the minor groove of DNA. Moreover, 1 trigger the condensation of CT–DNA into compact globules and rod-shaped morphology revealing electrostatic and intermolecular π–π interactions of ligand moiety present in the DNA–bound complexes. Interestingly, 1 does not produce much hemolysis even at higher concentration of 100 μM. The work is expected to encourage the development of a newer metal complex whose ultimate target is DNA.