title: DNA interactions of cobalt(III) mixed-polypyridyl complexes containing asymmetric ligands.
abstract: Three novel asymmetric ligands, 3-(pyridine-2-yl)-5,6-diphenyl-as-triazine (pdtb), 3-(pyridine-2-yl)-as-triazino[5,6-f]acenaphthylene (pdta) and 3-(pyridine-2-yl)-as-triazino[5,6-f]phenanthroline (pdtp) and their cobalt(III) complexes have been synthesized and characterized. Binding of the three complexes with calf thymus DNA (CT-DNA) has been investigated by spectroscopic methods, viscosity, cyclic voltammetry, and electrophoresis measurements. The experimental results indicate that the size and shape of the intercalated ligand have a marked effect on the binding affinity of complexes to CT-DNA. Complexes 2 and 3 have also been found to promote cleavage of plasmid pBR322 DNA from the supercoiled form I to the open circular form II upon irradiation.
authors.affiliation: Department of Chemistry, Sun Yat-Sen University, Guangzhou 510275, PR China.
authors.forename: Xiang-Li
authors.initials: XL
authors.lastname: Wang
authors.forename: Hui
authors.initials: H
authors.lastname: Chao
authors.forename: Hong
authors.initials: H
authors.lastname: Li
authors.forename: Xian-Lan
authors.initials: XL
authors.lastname: Hong
authors.forename: Yun-Jun
authors.initials: YJ
authors.lastname: Liu
authors.forename: Li-Feng
authors.initials: LF
authors.lastname: Tan
authors.forename: Liang-Nian
authors.initials: LN
authors.lastname: Ji
mesh_terms: D000073:Acenaphthenes / Q000138:chemical synthesis / Q000737:chemistry*; D000818:Animals; D002417:Cattle; D003035:Cobalt / Q000737:chemistry*; D004247:DNA / Q000737:chemistry*; D008024:Ligands; D009942:Organometallic Compounds / Q000138:chemical synthesis / Q000737:chemistry*; D010618:Phenanthrolines / Q000138:chemical synthesis / Q000737:chemistry*; D010777:Photochemistry; D010957:Plasmids / Q000737:chemistry*; D011725:Pyridines / Q000138:chemical synthesis / Q000737:chemistry*; D014227:Triazines / Q000138:chemical synthesis / Q000737:chemistry*
chemical_list: C498748:3-(pyridine-2-yl)-5,6-diphenyl-triazine; C498749:3-(pyridine-2-yl)-as-triazino(5,6-f)acenaphthylene; C498750:3-(pyridine-2-yl)-as-triazino(5,6-f)phenanthrolin; D000073:Acenaphthenes; D008024:Ligands; D009942:Organometallic Compounds; D010618:Phenanthrolines; D011725:Pyridines; D014227:Triazines; D003035:Cobalt; D004247:DNA; C427203:calf thymus DNA