title: Synthesis, characterization and DNA binding of ruthenium(II) complexes containing the atatp ligand.
abstract: Acenaphtheno[1,2-b]-1,4,8,9-tetraazatriphenylene (atatp) and its complexes [Ru(L)2atatp](ClO4)2 x nH2O (L = 2,2'-bipyridine (bpy), n=2 (1); 1,10-phenanthroline (phen), n=2 (2); and 2,9-dimethyl-1,10-phenanthroline (dmp), n=1 (3)) have been synthesized and characterized by elemental analyses and 1H NMR. The spectral and electrochemical properties of these complexes are also examined. Complexes 1 and 2 display bright luminescence in acetonitrile but very weak luminescence in water solution. However, complex 3 is not luminescent in either solvent. The interaction of the complexes with calf thymus DNA (CT-DNA) has been studied by absorption, emission and viscosity measurements. The intrinsic binding constants of complexes 1 and 2 are 7.6 x 10(4) and 8.8 x 10(4) M(-1) respectively. The relatively low affinities of complexes 1 and 2 with DNA may arise from the atatp ligand, indicating that the size and shape of the intercalated ligand have a marked effect on the strength of interaction. Complexes 1 and 2 bind with CT-DNA in an intercalative mode but complex 3 in a non-intercalative one, showing that changing the ancillary ligand affects not only the binding magnitude, but also the binding mode of the interaction.
authors.affiliation: Department of Chemistry, Zhongshan University, Guangzhou, China.
authors.forename: Q X
authors.initials: QX
authors.lastname: Zhen
authors.forename: Q L
authors.initials: QL
authors.lastname: Zhang
authors.forename: J G
authors.initials: JG
authors.lastname: Liu
authors.forename: B H
authors.initials: BH
authors.lastname: Ye
authors.forename: L N
authors.initials: LN
authors.lastname: Ji
authors.forename: L
authors.initials: L
authors.lastname: Wang
mesh_terms: D000073:Acenaphthenes / Q000138:chemical synthesis*; D004247:DNA / Q000378:metabolism*; D007501:Iron / Q000494:pharmacology; D007700:Kinetics; D008024:Ligands; D008163:Luminescent Measurements; D008956:Models, Chemical; D010618:Phenanthrolines / Q000138:chemical synthesis*; D012428:Ruthenium / Q000378:metabolism*; D013053:Spectrophotometry; D014783:Viscosity
chemical_list: D000073:Acenaphthenes; D008024:Ligands; D010618:Phenanthrolines; C415335:acenaphtheno(1,2-b)-1,4,8,9-tetraazatriphenylene; D012428:Ruthenium; D004247:DNA; D007501:Iron