The novel dinuclear copper complex [Cu2（H20）2（DMF）2（L）2] （1, H2L = 5-phenyl- 2H-1,2,3-triazole-4-carboxylic acid, DMF = N,N-dimethyl-formamide） has been synthesized and characterized by X-ray single-crystal di...The novel dinuclear copper complex [Cu2（H20）2（DMF）2（L）2] （1, H2L = 5-phenyl- 2H-1,2,3-triazole-4-carboxylic acid, DMF = N,N-dimethyl-formamide） has been synthesized and characterized by X-ray single-crystal diffraction. The compound crystallizes in triclinic system, space group P1 with a = 9.591, b = 10.508, c = 15.515A,β = 75.11°, V= 1446.2 A3, Z= 2, Mr = 683.62, Dc = 1.570 g/cm3, μ = 1.531 mm^-1, F（000） = 700, the final R = 0.0404 and wR = 0.1130 for 5327 observed reflections with I 〉 2σ（I）. In each unit of the complex, two Cu2＋ ions coordinated with two triazole ligands to form a dimeric [5,6,5] tricyclic structure. The central Cu atom is five-coordinated, and each copper atom shows a square pyramidal geometry. The crystal structure is stabilized by the inversion-related O-H…O hydrogen bond and C-H…O hydrogen bonding interactions to form a layer structure. Fluorescent spectra show an obvious quenching of fluorescence compared with free 1,2,3-triazole ligand. The results of agarose gel electrophoresis indicate that this complex can cleave the plasmid supercoiled DNA within shorter time in the 50-folds excess of ascorbate under physiological conditions, providing a new example in the research for artificial metal nucleic acid enzyme.展开更多
A novel potential tridentate Schiff base was prepared by condensing equimolar quantities of 2-hydroxyacetophenone and 2-aminopyrimidine in methanol. This ligand was versatile in forming a series of complexes with lant...A novel potential tridentate Schiff base was prepared by condensing equimolar quantities of 2-hydroxyacetophenone and 2-aminopyrimidine in methanol. This ligand was versatile in forming a series of complexes with lanthanide ions such as La（III）, Pr（III）, Nd（III）, Sm（III）, Gd（III）, Dy（III） and Yb（III）. The ligand and the metal complexes were characterized through elemental analysis, molar conductance, UV-Visible, IR, 1H NMR, and mass spectral studies. The spectral studies indicated that the ligand was coordinated to the metal ion in neutral tridentate fashion through the azomethine nitrogen, one of the nitrogen atoms in the pyrimidine ring and the phenolic oxygen without deprotonation. Thermal decomposition and luminescence property of lanthanum（III） complex were also examined. The X-ray diffraction patterns showed the crystalline nature of the ligand and its lanthanum（III） complex. The DNA cleavage studies of the ligand and the metal complexes were carried out and it was observed that the lanthanum（III） and neo-dymium（III） complexes cleaved the pUC19 DNA effectively. The ligand and the metal complexes were screened for their antibacte-rial activities. The metal complexes were found to be more potent bactericides than the ligand.展开更多
Two new complexes： [Cu（TBZ）（bipy）Cl]Cl[H2O （1） and [Cu（TBZ）（phen）CI]CloH20 （2） [TBZ=2-（4＇-thiazolyl）- benzimidazole, phen = 1,10-phenanthroline and bipy =2,2＇-bipyridine] have been synthesized and cha...Two new complexes： [Cu（TBZ）（bipy）Cl]Cl[H2O （1） and [Cu（TBZ）（phen）CI]CloH20 （2） [TBZ=2-（4＇-thiazolyl）- benzimidazole, phen = 1,10-phenanthroline and bipy =2,2＇-bipyridine] have been synthesized and characterized by elemental analysis, molar conductivity, IR, and UV-vis methods. Complex 2, structurally characterized by single-crystal X-ray crystallography, crystallizes in the monoclinic space group P21/c in a unit cell of a = 0.85257（12） nm, b=2.5358（4） nm, c=1.15151（13） nm, β=118.721（8）°, V=2.183.2（5） nm^3, Z=4, Dc=1.624 gocm 3, μ= 1.367 mm^-1. The complexes, free ligands and chloride copper（II） salt were each tested for their ability to inhibit the growth of two gram-positive （B. subtilis and S. aureus） and two gram-negative （Salmonella and E. coli） bacteria. The complexes showed good antibacterial activities against the microorganisms. The interaction between the com- plexes and calf thymus DNA in aqueous solution was investigated adopting electronic absorption spectroscopy, fluorescence spectroscopy, viscosity measurements and cyclic voltammetry. Results suggest that the two complexes can bind to DNA by intercalative mode. In addition, the result of agarose gel electrophoresis suggested that the complexes can cleave the plasmid DNA at physiological pH and room temperature. Mechanistic studies with different inhibiting reagents reveal that hydroxyl radicals, and a singlet oxygen-like copper-oxo species are all involved in the DNA scission process mediated by the complexes.展开更多
The title complex [ NH3 CH2 CH （ NH2 ） CH3 ]2 [ M （ Ⅵ ） O2 （ OC6 H4 O）2 ] （ M = Mo0. 6 W0.4 ） was synthesized via a simple solution-phase ehemieal route. The determination of single erystal X-ray diffraction ...The title complex [ NH3 CH2 CH （ NH2 ） CH3 ]2 [ M （ Ⅵ ） O2 （ OC6 H4 O）2 ] （ M = Mo0. 6 W0.4 ） was synthesized via a simple solution-phase ehemieal route. The determination of single erystal X-ray diffraction revealed that the title eompound is erystallized in a monoelinie system with P2（ 1 ）/n spaee group, a = 1. 0913（10） nm, b = 1. 0442（10） nm, c=1.8842（19） nm, α=90°, β=96.530（17）°, γ=90°, Z=4, and V=2.133（4） nm^3. The mononuelear anionie unit [ M （ Ⅵ ） O2 （ 0C6 H4 O） 2 ] 2 - displays ehiral pseudo-oetahedral [ MO6 ] eoordination geometry and is linked by ehiral eations via hydrogen bond and π…π stacking interaetion. The transmission electron microseopy images show that the title eomplex is eomprised of nano-partieles with diameters ranging from 20 to 50 nm. The NMR study shows the ^1H downfield chemical shifts of [ NH3 CHa Hb CH （ NH2 ） CH3 ]^＋ eations in the title eomplex when it is mixed with adenosine-triphosphate（ ATP）, and the chemical shift difference between Ha and Hb is inereased greatly, and most of the eateeholate ligands dissociate from the eentral metal atoms. The DNA cleavage aetivity experiment reveals that DNA eleavage promoted by the title eomplex is lower than that by Na2 MoO4 whieh possesses antitumor propetty, but higher than that by Na2WO4.展开更多
基金supported by the National Natural Science Foundation of China(No.21002076)Wuhan Youth Chenguang Program of Science and Technology(No.201271031374)
文摘The novel dinuclear copper complex [Cu2（H20）2（DMF）2（L）2] （1, H2L = 5-phenyl- 2H-1,2,3-triazole-4-carboxylic acid, DMF = N,N-dimethyl-formamide） has been synthesized and characterized by X-ray single-crystal diffraction. The compound crystallizes in triclinic system, space group P1 with a = 9.591, b = 10.508, c = 15.515A,β = 75.11°, V= 1446.2 A3, Z= 2, Mr = 683.62, Dc = 1.570 g/cm3, μ = 1.531 mm^-1, F（000） = 700, the final R = 0.0404 and wR = 0.1130 for 5327 observed reflections with I 〉 2σ（I）. In each unit of the complex, two Cu2＋ ions coordinated with two triazole ligands to form a dimeric [5,6,5] tricyclic structure. The central Cu atom is five-coordinated, and each copper atom shows a square pyramidal geometry. The crystal structure is stabilized by the inversion-related O-H…O hydrogen bond and C-H…O hydrogen bonding interactions to form a layer structure. Fluorescent spectra show an obvious quenching of fluorescence compared with free 1,2,3-triazole ligand. The results of agarose gel electrophoresis indicate that this complex can cleave the plasmid supercoiled DNA within shorter time in the 50-folds excess of ascorbate under physiological conditions, providing a new example in the research for artificial metal nucleic acid enzyme.
文摘A novel potential tridentate Schiff base was prepared by condensing equimolar quantities of 2-hydroxyacetophenone and 2-aminopyrimidine in methanol. This ligand was versatile in forming a series of complexes with lanthanide ions such as La（III）, Pr（III）, Nd（III）, Sm（III）, Gd（III）, Dy（III） and Yb（III）. The ligand and the metal complexes were characterized through elemental analysis, molar conductance, UV-Visible, IR, 1H NMR, and mass spectral studies. The spectral studies indicated that the ligand was coordinated to the metal ion in neutral tridentate fashion through the azomethine nitrogen, one of the nitrogen atoms in the pyrimidine ring and the phenolic oxygen without deprotonation. Thermal decomposition and luminescence property of lanthanum（III） complex were also examined. The X-ray diffraction patterns showed the crystalline nature of the ligand and its lanthanum（III） complex. The DNA cleavage studies of the ligand and the metal complexes were carried out and it was observed that the lanthanum（III） and neo-dymium（III） complexes cleaved the pUC19 DNA effectively. The ligand and the metal complexes were screened for their antibacte-rial activities. The metal complexes were found to be more potent bactericides than the ligand.
文摘Two new complexes： [Cu（TBZ）（bipy）Cl]Cl[H2O （1） and [Cu（TBZ）（phen）CI]CloH20 （2） [TBZ=2-（4＇-thiazolyl）- benzimidazole, phen = 1,10-phenanthroline and bipy =2,2＇-bipyridine] have been synthesized and characterized by elemental analysis, molar conductivity, IR, and UV-vis methods. Complex 2, structurally characterized by single-crystal X-ray crystallography, crystallizes in the monoclinic space group P21/c in a unit cell of a = 0.85257（12） nm, b=2.5358（4） nm, c=1.15151（13） nm, β=118.721（8）°, V=2.183.2（5） nm^3, Z=4, Dc=1.624 gocm 3, μ= 1.367 mm^-1. The complexes, free ligands and chloride copper（II） salt were each tested for their ability to inhibit the growth of two gram-positive （B. subtilis and S. aureus） and two gram-negative （Salmonella and E. coli） bacteria. The complexes showed good antibacterial activities against the microorganisms. The interaction between the com- plexes and calf thymus DNA in aqueous solution was investigated adopting electronic absorption spectroscopy, fluorescence spectroscopy, viscosity measurements and cyclic voltammetry. Results suggest that the two complexes can bind to DNA by intercalative mode. In addition, the result of agarose gel electrophoresis suggested that the complexes can cleave the plasmid DNA at physiological pH and room temperature. Mechanistic studies with different inhibiting reagents reveal that hydroxyl radicals, and a singlet oxygen-like copper-oxo species are all involved in the DNA scission process mediated by the complexes.
文摘The title complex [ NH3 CH2 CH （ NH2 ） CH3 ]2 [ M （ Ⅵ ） O2 （ OC6 H4 O）2 ] （ M = Mo0. 6 W0.4 ） was synthesized via a simple solution-phase ehemieal route. The determination of single erystal X-ray diffraction revealed that the title eompound is erystallized in a monoelinie system with P2（ 1 ）/n spaee group, a = 1. 0913（10） nm, b = 1. 0442（10） nm, c=1.8842（19） nm, α=90°, β=96.530（17）°, γ=90°, Z=4, and V=2.133（4） nm^3. The mononuelear anionie unit [ M （ Ⅵ ） O2 （ 0C6 H4 O） 2 ] 2 - displays ehiral pseudo-oetahedral [ MO6 ] eoordination geometry and is linked by ehiral eations via hydrogen bond and π…π stacking interaetion. The transmission electron microseopy images show that the title eomplex is eomprised of nano-partieles with diameters ranging from 20 to 50 nm. The NMR study shows the ^1H downfield chemical shifts of [ NH3 CHa Hb CH （ NH2 ） CH3 ]^＋ eations in the title eomplex when it is mixed with adenosine-triphosphate（ ATP）, and the chemical shift difference between Ha and Hb is inereased greatly, and most of the eateeholate ligands dissociate from the eentral metal atoms. The DNA cleavage aetivity experiment reveals that DNA eleavage promoted by the title eomplex is lower than that by Na2 MoO4 whieh possesses antitumor propetty, but higher than that by Na2WO4.
