New transition metal complexes of 9,10-phenanthrenequinone p-toluyl hydrazone Schiff base: Synthesis, spectroscopy, DNA and HSA interactions, antimicrobial, DFT and docking studies

The new complexes of Cu (II) and Ni (II) of a tridentate Schiff base ligand derived from 9,10-phenanthrenequinone and p-toluic hydrazide have been synthesized and characterized by elemental analysis, electrical conductometry, FT-IR, Mass, NMR and UV-Vis. The DFT calculations were carried out at B3LYP/6-31G*(d) level for the determination of the optimized structure of the ligand and its complexes. The as-synthesized compounds were screened for their antimicrobial activity. Also, their binding behavior with fish salmon-DNA (FS-DNA) and human serum albumin (HSA) were studied by different kinds of spectroscopic and molecular modeling techniques. The fluorescence data at different temperatures were applied in order to estimate the thermodynamics parameters of interactions of ligand and its complexes with DNA and HSA. The results showed that the as-made compounds could bind to FS-DNA and HSA via the groove binding as the major binding mode. According to molecular docking calculation and competitive binding experiments, these compounds bind to the minor groove of DNA and hydrophobic residues located in the subdomain IB of HSA. In addition, the molecular docking results kept in good consistence with experimental data.