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《Journal of Coordination Chemistry》2012,65(20):3676-3687
DNA-binding properties of a number of ruthenium complexes with different polypyridine ligands are reported. The new polypyridine ligand BFIP (=2-benzo[b] furan-2-yl-1H-imidazo[4,5-f][1,10]phenanthroline) and its ruthenium complexes [Ru(bpy)2BFIP]2+ (bpy = 2,2′-bipyridine), [Ru(dmb)2BFIP]2+ (dmb = 4,4′-dimethyl-2,2′-bipyridine), and [Ru(phen)2BFIP]2+ (phen = 1,10-phenanthroline) have been synthesized and characterized by elemental analysis, mass spectra, IR, UV-Vis, 1H- and 13C-NMR, and cyclic voltammetry. The DNA binding of these complexes to calf-thymus DNA (CT-DNA) was investigated by spectrophotometric, fluorescence, and viscosity measurements. The results suggest that ruthenium(II) complexes bind to CT-DNA through intercalation. Photocleavage of pBR 322 DNA by these complexes was also studied, and [Ru(phen)2BFIP]2+ was found to be a much better photocleavage agent than the other two complexes. 相似文献
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《Journal of Coordination Chemistry》2012,65(4):660-669
Tris(N-ethylbenzimidazol-2-ylmethyl)amine (Etntb), [Mn(Etntb)(DMF)(H2O)](pic)2 (1), and [Ni(Etntb)(DMF)(H2O)](pic)2 (2) (pic?=?picrate) have been synthesized and characterized by elemental analyses, molar conductivities, UV–Visible spectra, and IR spectra. Single-crystal X-ray diffraction revealed that the complexes have the same arrangement with distorted octahedral coordination geometries. DNA-binding properties of the free ligand, 1, and 2 have been investigated by electronic absorption, fluorescence, and viscosity measurements. The results suggest that the ligand and its complexes bind DNA via intercalation, and their binding affinity for DNA follows the order 2?>?1?> ligand. 相似文献
998.
《Journal of Coordination Chemistry》2012,65(24):4268-4279
Two cobalt(II) complexes [Co(QCT)2]·Cl·1.5H2O (1) (QCT = quinoline-2-carboxaldehyde thiosemicarbazone) and [Co(QCMT)(CH3OH)Cl2] (2) (QCMT = quinoline-2-carboxaldehyde N4-methyl-thiosemicarbazone) have been synthesized and structurally characterized. Complex 1 crystallizes in a triclinic system with space group P–1 and complex 2 crystallizes in a monoclinic system with space group P2(1)/n. In both complexes the cobalt(II) center is six coordinated with distorted octahedral geometry. The interactions of two complexes with CT-DNA were investigated by electronic absorption spectra, circular dichroism (CD) spectra and fluorescence spectra. Results suggest that the complexes bind to DNA via groove binding mode, and complex 2 has stronger binding ability than complex 1. The in vitro cytotoxicity has been tested against the human lung adenocarcinoma cell line A-549, cisplatin-resistant cell line A-549/CDDP, and human breast adenocarcinoma cell line MCF-7. Complex 2 is more cytotoxic than complex 1, and both of them show higher cytotoxicity than the parent ligands alone. Compared with cisplatin, the two cobalt(II) complexes are more active against A-549/CDDP and MCF-7 cell lines at most experimental concentrations. Notably, although complex 2 is found to be less effective than cisplatin against the parent cell line A-549, it is much more effective than cisplatin against the resistant cell A-549/CDDP. 相似文献
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《Journal of Coordination Chemistry》2012,65(11):1977-1990
A cationic porphyrin–anthraquinone hybrid and its Zn(II), Cu(II), Co(III), and Mn(III) complexes were synthesized and their interactions with duplex DNA were studied using a combination of absorption, fluorescence titration, circular dichroism spectroscopy, thermal DNA denaturation, viscosity measurements, gel electrophoresis, and gas chromatography. Metal coordination induces intermolecular steric hindrance and thus the metal hybrids have smaller DNA binding affinities than the free base hybrid; the steric hindrance could relax the intermolecular aggregation and increase 1O2 generation of the metal hybrids. The DNA photocleavage abilities of these hybrids were investigated. 相似文献
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