13C and 99Ru-NMR chendcal shifts are reported for the ruthenium(II) tris complexes of5-substitUted 1,10-phenanthrolines. It has been found that both of them are affected by the substituents on the phenanthrolines in a...13C and 99Ru-NMR chendcal shifts are reported for the ruthenium(II) tris complexes of5-substitUted 1,10-phenanthrolines. It has been found that both of them are affected by the substituents on the phenanthrolines in a direction consistent with that expected from the electron withdrawing ability of the substituent.展开更多
A new ruthenium polypyridine complex, [Ru(phen) 2(pMIP)] 2+(phen=1,10-phenanthroline, pMIP=2-(4-methylphenyl)imidazo phenanthroline), was synthesized and characterized by elementary analysis, MS and 1H NMR. Spectrosco...A new ruthenium polypyridine complex, [Ru(phen) 2(pMIP)] 2+(phen=1,10-phenanthroline, pMIP=2-(4-methylphenyl)imidazo phenanthroline), was synthesized and characterized by elementary analysis, MS and 1H NMR. Spectroscopic methods have been carried out on the interaction mechanism of the Ru (Ⅱ) complex with yeast tRNA systematically. The experimental results indicate that the complex binds to yeast tRNA with an intercalative mode possibly, and interacts with yeast tRNA enantioselectively. The experimental results also suggest that spectroscopic method is effective on studying the interaction mechanism of Ru (Ⅱ) complexes with RNA. Information obtained from the study is potentially useful in the design of new RNA-targeting drugs.展开更多
The interactions between two trinuclear Ru（II） complexes and calf thymus DNA（CT DNA） were studied via absorption spectroscopy, reverse salt titrations, binding stoichiometry, DNA melting experiments, as well as vi...The interactions between two trinuclear Ru（II） complexes and calf thymus DNA（CT DNA） were studied via absorption spectroscopy, reverse salt titrations, binding stoichiometry, DNA melting experiments, as well as viscosity measurement. The results indicate that complexes 1 and 2 bind to DNA via the interaction of the planar π-delocalized system of the complexes with intrinsic binding constants of 4.18 × 10^5 and 3.85 × 10^6 L/tool, respectively, and non-electrostatic binding free energy makes a predominant contribution to the binding free energy. The in vitro cytotoxic activity of complexes 1 and 2 was evaluated by the MTT[3-（4,5-dimethylthiazol-2-yl）-2,5-diphenyl- 2H-tetrazolium bromide] method. Complex I shows higher anticancer potency than complex 2 against four tumor cell lines. Further mechanism study indicates that complexes 1 and 2 can cause cell cycle arrest in the G2/M phase.展开更多
The interaction of ruthenium polypyridyl complex with DNA has been studied by isothermal titration calorimetry (ITC). The results show that complex [Ru(phen)2PMIP]2+ {phen=1,10-phenanthroline, PMIP=2-(4-methylphenyl)i...The interaction of ruthenium polypyridyl complex with DNA has been studied by isothermal titration calorimetry (ITC). The results show that complex [Ru(phen)2PMIP]2+ {phen=1,10-phenanthroline, PMIP=2-(4-methylphenyl)imidazo1,10-phenanthroline} interacts with calf thymus DNA (CT DNA) in terms of a model for a single set of identical sites through intercalation. The results are in agreement with our previous observations from spectroscopic methods and viscosity measurements. In addition, the results further show that the driving force for DNA binding with the complex is mainly driven by the enthalpy changes, and the contribution from the entropy changes to this driving force is negligible.展开更多
Two enantiomerically pure polypyridyl ruthenium(Ⅱ) complexes Δ- and Λ-[Ru(bpy) 2HPIP](PF 6) 2{HPIP=2-(2-hydroxyphenyl)imidazo[4,5-f][1,10]phenanthroline} were synthesized and characterized. DNA-binding studies indi...Two enantiomerically pure polypyridyl ruthenium(Ⅱ) complexes Δ- and Λ-[Ru(bpy) 2HPIP](PF 6) 2{HPIP=2-(2-hydroxyphenyl)imidazo[4,5-f][1,10]phenanthroline} were synthesized and characterized. DNA-binding studies indicated that both enantiomers bound to calf thymus DNA by intercalation, the Δ- enantiomer exhibited a stronger binding affinity than the Λ- enantiomer. Upon irradiation at 302 nm, both enantiomers were found to promote cleavage of plasmid pBR 322 DNA from the supercoiled form Ⅰ to the open circular form Ⅱ, but the Δ-enantiomer exhibited a higher cleaving efficiency for DNA due to the different binding affinities to DNA. The cleaving mechanisms for Δ- and Λ-[Ru(bpy) 2HPIP] 2+ were identical, the hydroxyl radical(OH ·) was likely to be the reactive specie responsible for the cleavage of plasmid pBR 322, and the photoreduction of Ru(Ⅱ) complex with concomitant hydroxide oxidation was the important step in the DNA cleavage reaction.展开更多
文摘13C and 99Ru-NMR chendcal shifts are reported for the ruthenium(II) tris complexes of5-substitUted 1,10-phenanthrolines. It has been found that both of them are affected by the substituents on the phenanthrolines in a direction consistent with that expected from the electron withdrawing ability of the substituent.
文摘A new ruthenium polypyridine complex, [Ru(phen) 2(pMIP)] 2+(phen=1,10-phenanthroline, pMIP=2-(4-methylphenyl)imidazo phenanthroline), was synthesized and characterized by elementary analysis, MS and 1H NMR. Spectroscopic methods have been carried out on the interaction mechanism of the Ru (Ⅱ) complex with yeast tRNA systematically. The experimental results indicate that the complex binds to yeast tRNA with an intercalative mode possibly, and interacts with yeast tRNA enantioselectively. The experimental results also suggest that spectroscopic method is effective on studying the interaction mechanism of Ru (Ⅱ) complexes with RNA. Information obtained from the study is potentially useful in the design of new RNA-targeting drugs.
基金Supported by the National Natural Science Foundation of China（No.21301034） and the Natural Science Foundation of Guangdong Province, China（No.S2013040014083）.
文摘The interactions between two trinuclear Ru（II） complexes and calf thymus DNA（CT DNA） were studied via absorption spectroscopy, reverse salt titrations, binding stoichiometry, DNA melting experiments, as well as viscosity measurement. The results indicate that complexes 1 and 2 bind to DNA via the interaction of the planar π-delocalized system of the complexes with intrinsic binding constants of 4.18 × 10^5 and 3.85 × 10^6 L/tool, respectively, and non-electrostatic binding free energy makes a predominant contribution to the binding free energy. The in vitro cytotoxic activity of complexes 1 and 2 was evaluated by the MTT[3-（4,5-dimethylthiazol-2-yl）-2,5-diphenyl- 2H-tetrazolium bromide] method. Complex I shows higher anticancer potency than complex 2 against four tumor cell lines. Further mechanism study indicates that complexes 1 and 2 can cause cell cycle arrest in the G2/M phase.
文摘The interaction of ruthenium polypyridyl complex with DNA has been studied by isothermal titration calorimetry (ITC). The results show that complex [Ru(phen)2PMIP]2+ {phen=1,10-phenanthroline, PMIP=2-(4-methylphenyl)imidazo1,10-phenanthroline} interacts with calf thymus DNA (CT DNA) in terms of a model for a single set of identical sites through intercalation. The results are in agreement with our previous observations from spectroscopic methods and viscosity measurements. In addition, the results further show that the driving force for DNA binding with the complex is mainly driven by the enthalpy changes, and the contribution from the entropy changes to this driving force is negligible.
文摘Two enantiomerically pure polypyridyl ruthenium(Ⅱ) complexes Δ- and Λ-[Ru(bpy) 2HPIP](PF 6) 2{HPIP=2-(2-hydroxyphenyl)imidazo[4,5-f][1,10]phenanthroline} were synthesized and characterized. DNA-binding studies indicated that both enantiomers bound to calf thymus DNA by intercalation, the Δ- enantiomer exhibited a stronger binding affinity than the Λ- enantiomer. Upon irradiation at 302 nm, both enantiomers were found to promote cleavage of plasmid pBR 322 DNA from the supercoiled form Ⅰ to the open circular form Ⅱ, but the Δ-enantiomer exhibited a higher cleaving efficiency for DNA due to the different binding affinities to DNA. The cleaving mechanisms for Δ- and Λ-[Ru(bpy) 2HPIP] 2+ were identical, the hydroxyl radical(OH ·) was likely to be the reactive specie responsible for the cleavage of plasmid pBR 322, and the photoreduction of Ru(Ⅱ) complex with concomitant hydroxide oxidation was the important step in the DNA cleavage reaction.
