title: Synthesis and DNA binding studies of Ni(II), Co(II), Cu(II) and Zn(II) metal complexes of N1,N5-bis[pyridine-2-methylene]-thiocarbohydrazone Schiff-base ligand.
abstract: The thiocarbohydrazone Schiff-base ligand with a nitrogen and sulphur donor was synthesized through condensation of pyridine-2-carbaldehyde and thiocarbohydrazide. Schiff-base ligands have the ability to conjugate with metal salts. A series of metal complexes with a general formula [MCl2(H2L)]·nH2O (MNi, Co, Cu and Zn) were synthesized by forming complexes of the N1,N5-bis[pyridine-2-methylene]-thiocarbohydrazone (H2L) Schiff-base ligand. These metal complexes and ligand were characterized by using ultraviolet-visible (UV-Vis), Fourier Transform Infrared (FT-IR), 1H and 13C NMR spectroscopy and mass spectroscopy, physicochemical characterization, CHNS and conductivity. The biological activity of the synthesized ligand was investigated by using Escherichia coli DNA as target. The DNA interaction of the synthesized ligand and complexes on E. coli plasmid DNA was investigated in the aqueous medium by UV-Vis spectroscopy and the binding constant (Kb) was calculated. The DNA binding studies showed that the metal complexes had an improved interaction due to trans-geometrical isomers of the complexes than ligand isomers in cis-positions.
authors.affiliation: Department of Chemical Technology, University of Johannesburg, P.O. Box 17011, Doornfontein 2028, South Africa.
authors.forename: A D
authors.initials: AD
authors.lastname: Tiwari
authors.forename: A K
authors.initials: AK
authors.lastname: Mishra
authors.forename: S B
authors.initials: SB
authors.lastname: Mishra
authors.forename: B B
authors.initials: BB
authors.lastname: Mamba
authors.forename: B
authors.initials: B
authors.lastname: Maji
authors.forename: S
authors.initials: S
authors.lastname: Bhattacharya
mesh_terms: D003035:Cobalt / Q000737:chemistry* / Q000378:metabolism; D056831:Coordination Complexes / Q000138:chemical synthesis* / Q000378:metabolism*; D003300:Copper / Q000737:chemistry* / Q000378:metabolism; D004269:DNA, Bacterial / Q000737:chemistry / Q000378:metabolism*; D004578:Electron Spin Resonance Spectroscopy; D004926:Escherichia coli / Q000235:genetics; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D015394:Molecular Structure; D009532:Nickel / Q000737:chemistry* / Q000378:metabolism; D009942:Organometallic Compounds / Q000138:chemical synthesis* / Q000378:metabolism*; D011725:Pyridines / Q000737:chemistry; D012545:Schiff Bases; D013055:Spectrophotometry, Infrared; D015032:Zinc / Q000737:chemistry* / Q000378:metabolism
chemical_list: D056831:Coordination Complexes; D004269:DNA, Bacterial; D009942:Organometallic Compounds; D011725:Pyridines; D012545:Schiff Bases; D003035:Cobalt; D003300:Copper; D009532:Nickel; D015032:Zinc