Synthesis, spectral characterisation and pharmacological studies on Co(II), Ni(II), Cu(II) and Zn(II) bis-Schiff base complexes derived from 4-hydroxybenzohydrazide

The transition metal(II) chelates have been prepared by the reactions of bis-Schiff base ligands derived from 4-hydroxy benzohydrazide and isophthalaldehyde/ o-phthaldehyde in 1:1 metal to ligand ratio. The formed ligands and their metal complexes have been investigated by elemental analysis, different spectroscopic and thermal analyses techniques. The low molar conductance values give the non-electrolytic nature of the metal(II) chelates. From the spectroscopic observations of complexes, the molecular formula is found to be [M(Ln)(2)Cl-2] (where M=Co(II), Ni(II), Cu(II) and Zn(II), n=1 and 2) and the tetradentate N2O2 donor sites of ligands is attached to the metal centre. The docking results predicts that the protein with ligands have good interaction energy. All formed complexes have efficient antibacterial activity than ligand for tested pathogens. The mode of binding interaction of ct-DNA and Cu(II) complexes gives the intercalative binding with hypochromism shifts using electronic titrations method. In electrophoresis, cleavages of PUC18DNA to cleave effectively with Cu(II) complexes in the presence of hydroxyl radicals. The antioxidant assay of DPPH radical scavenging activity of tested compounds shows good results, when compared to ascorbic acid as standard. The anticancer MTT assay of Cu(II) complexes tested against MCF-7 cancerous cells gives the promising therapeutic activity.