Synthesis, characterization, X-ray crystallography and DNA binding activities of Co(III) and Cu(II) complexes with a pyrimidine-based Schiff base ligand

A new pyrimidine based ‘NNO’ tridentate ligand 2,4-dihydroxyacetophenone-4,6-dimethyhydrazino pyrimidine (H2MHyP) (complex I) has been synthesized and characterized by elemental analyses, mass, IR 1H NMR spectra and X-ray crystallographic studies. The Coordination mode of the synthesized ligand has been established by solid state isolation and physico-chemical identification of Co(III) and Cu(II) complexes, [Co(HMHyP)2]Cl (complex II), [Co(HMHyP)2]Br (complex III) and [Cu(HMHyP)]NO3 (complex IV) respectively. All the reported coordination complexes are 1:1 electrolytic cationic species and the ligand behaves as a monodeprotonated ‘NNO’ tridentate one in all the complex species. IR spectral data indicate that the coordination of each of the metal centre of the complexes occurs through the pyrimidine nitrogen, azomethine nitrogen and hydroxyl oxygen atoms. X-ray crystallographic data have authenticated a CoN4O2 octahedral coordination for II and III (Triclinic (P-1) and Monoclinic (P21/n), respectively) and a CuN2O2 square planar coordination for IV (Triclinic (P-1)). All the synthesized compounds were tested for their DNA binding abilities and their mode of binding with DNA. Compounds II, III & IV show potential DNA binding activities with Salmon Testis DNA.