title: Oxidative DNA cleavage mediated by a new copper (II) terpyridine complex: crystal structure and DNA binding studies.
abstract: The copper (II) complex [Cu(Itpy)(2)](ClO(4))(2) (1), (Itpy=imidazole terpyridine) has been synthesized and structurally characterized. Crystal structure of the complex shows the complex to be a monomeric copper (II) species with two Itpy ligands coordinated to the metal ion to give a six coordinate complex. The complex has a distorted octahedral geometry with axial elongation. Variable temperature crystal structure data shows dynamic nature of the Jahn-Teller distortion. The complex is an avid DNA binder with a binding constant of 4.26+/-0.20x10(3)M(-1). Observed changes in the viscosity and circular dichroic spectrum of calf thymus DNA solution in the presence of complex 1 suggests intercalative binding of complex 1 to DNA. The complex cleaves supercoiled pBR322 DNA oxidatively in the presence of hydrogen peroxide.
authors.affiliation: Chemical Laboratory, Central Leather Research Institute, Adyar, Chennai 600 020, Tamil Nadu, India.
authors.forename: V
authors.initials: V
authors.lastname: Uma
authors.forename: M
authors.initials: M
authors.lastname: Kanthimathi
authors.forename: T
authors.initials: T
authors.lastname: Weyhermuller
authors.forename: Balachandran Unni
authors.initials: BU
authors.lastname: Nair
mesh_terms: D000818:Animals; D002417:Cattle; D003300:Copper / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology*; D018360:Crystallography, X-Ray; D004247:DNA / Q000737:chemistry / Q000187:drug effects* / Q000378:metabolism*; D004578:Electron Spin Resonance Spectroscopy; D066298:In Vitro Techniques; D015394:Molecular Structure; D009942:Organometallic Compounds / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology*; D010084:Oxidation-Reduction; D011725:Pyridines / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology; D013053:Spectrophotometry
chemical_list: D009942:Organometallic Compounds; D011725:Pyridines; D003300:Copper; D004247:DNA