Tailoring, structural elucidation, DFT calculation, DNA interaction and pharmaceutical applications of some aryl hydrazone Mn(II), Cu(II) and Fe(III) complexes

Abstract

The current research focuses on the treatment of Mn(II) Cu(II) and Fe(III) metal ions with 1-(Benzhydrylidene-hydrazonomethyl)-naphthalen-2-ol (aryl hydrazone DHPN) ligand, producing three new solid complexes with substantial yields. In all mononuclear crystalline metal chelates with high thermal stability, different characterization techniques including infrared, UV–visible and NMR spectroscopies, elemental analyses and TGA revealed a tetra-coordination in DPHNCu complex and six-coordination for DPHNMn and DPHNFe complexes. Calculations based on Density Functional Theory (DFT) were used and offered a satisfactory explanation to better understands the electronic and structural properties of these metal chelates. Moreover, electronic absorption spectroscopy, hydrodynamic and electrophoresis measurements have revealed significant interactions of these novel complexes with calf thymus DNA through different binding modes. Accordingly, the Kb and ΔGb≠ values of such interaction followed that order: DPHNFe > DPHNMn > DPHNCu complex. In addition to, antibathogenic studies of the new metal chelates revealed that the latter had considerably high efficacy than the corresponding hydrazone ligand. The anti-proliferative activity of the compounds studied was also tested against various cancer cell lines and showed substantial cytotoxic activity. Moreover, antioxidant activity findings showed that the compounds tested had anti-oxidative activity relative to regular ascorbic acid. Furthermore, docking study of the investigated DPHN ligand and its complexes was performed to get a first insight of the interaction in the active site of the protein enzyme of the bacteria and fungi receptors.