Metal Complexes with Piperazine Ring Based N2O2 Ligands and their Biological Activity

This paper reports two ligands based on piperazine rings and their cobalt, copper, and zinc complexes, along with synthesis and characterization. Ligands were synthesized by direct condensation of chloroethanol and the ring-opening reaction of styrene oxide with piperazine and characterized by FT‒IR, UV‒Vis, mass spectrometry, and 1H‒NMR spectroscopic techniques. The metal complexes were synthesized in methanol and acetonitrile solvent using metal chloride salt and characterized with FT‒IR, UV‒Vis, mass spectrometry, 1H‒NMR, and electrochemical and thermal analysis. Complexes indicated a non-ionic nature in molar conductance data, and loss of coordinated solvent molecules during TGA analysis helped in the interpretation of the structure of complexes. DFT was employed to optimize the ligands and complexes. The moderate protein binding constant of the complexes with BSA favored albumin-based transportation through blood. DNA binding studies have been performed with CT-DNA, and a moderate binding constant value was observed. Molecular docking studies of selected complexes support hydrophilic interaction with BSA protein via grove binding in the DNA molecule.