title: Theoretical studies on the related properties of Co(III) polypyridyl complexes interacting with DNA.
abstract: Theoretical studies on the related properties of Co(III) polypyridyl complexes [Co(phen)(2)L](3+) (L: dppz = dipyrido[3,2-a:2',3'-c]phenazine; phen = 1,10-phenanthroline; dione = 1,10-phenanthroline-5,6-diketone) 1-3 interacting with DNA, including the DNA-binding, DNA-photocleavage and spectral properties, have been carried out. First, the full geometry-optimizations of these three complexes in their ground states were carried out in aqueous solution. The optimized structures of these three complexes were docked into DNA-base-pairs using the Dock6.0 program. Secondly, the binding modes of complexes 1-3 were revealed in detail and the trend in DNA-binding affinities was reasonably explained. Thirdly, the electronic absorption and emission spectra of docking model of the optimal complex 1 were calculated and simulated. The experimental intense absorption and emission bands of Co(Ш) complex 1 in the presence of DNA were explained in detail, in particular, the reason why the emission spectra of complex 1 in the presence of DNA are greatly stronger than those in the absence of DNA was theoretically elucidated. Finally, the DNA-photocleavage essential of complexes was explored and the DNA photocleavage efficiencies (φ), i.e., φ(1)>φ(2)>φ(3), was also reasonably explained.
authors.affiliation: College of Chemistry and Materials Science, Huaibei Normal University, Huaibei 235000, China. miaotifang@163.com
authors.forename: Ti-Fang
authors.initials: TF
authors.lastname: Miao
authors.forename: Shuang
authors.initials: S
authors.lastname: Li
authors.forename: Jun
authors.initials: J
authors.lastname: Li
authors.forename: Kang-Cheng
authors.initials: KC
authors.lastname: Zheng
mesh_terms: D003035:Cobalt / Q000737:chemistry*; D056831:Coordination Complexes / Q000737:chemistry*; D004247:DNA / Q000737:chemistry*; D007364:Intercalating Agents / Q000737:chemistry*; D008958:Models, Molecular; D056004:Molecular Dynamics Simulation; D010618:Phenanthrolines / Q000737:chemistry*; D010619:Phenazines / Q000737:chemistry*; D011725:Pyridines / Q000737:chemistry*
chemical_list: D056831:Coordination Complexes; D007364:Intercalating Agents; D010618:Phenanthrolines; D010619:Phenazines; D011725:Pyridines; D003035:Cobalt; D004247:DNA