Copper (II) complex derived from 2, 2'-pyridil ligand has been, demonstrated to cleave efficiently DNA at micromolar concentrations at room temperature and pH 7.25.
The reaction of N-tosylatirdine with 1,2-diaminopropane in dry benzene solution yields an intermediate H2L, N,N,N＇,N＇-tetrakis（2-（p-tolylsulfonyl）aminoethyl） propane-1,2-diamine. The mononuclear copper（Ⅱ） com...The reaction of N-tosylatirdine with 1,2-diaminopropane in dry benzene solution yields an intermediate H2L, N,N,N＇,N＇-tetrakis（2-（p-tolylsulfonyl）aminoethyl） propane-1,2-diamine. The mononuclear copper（Ⅱ） complex, [CuLH2O]·H2O, was synthesized by the reaction between the intermediate and copper（Ⅱ） in absolute methanol. The complex has been characterized by IR, UV-vis and X-ray diffraction technology, and its crystal crystallizes in the orthorhombic system, space group Pbca with a = 15.589（1）, b = 21.897（2）, c = 27.645（2） A, V = 9436.4（1）A^3, Dc = 1.352 g/cm^3, Z = 8, Mr = 960.68, F（000） = 4040, μ（MoKa） = 0.698 mm-1, S = 0.98, R = 0.0537 and wR = 0.1180 for 5804 observed reflections （I 〉 2σ（I））. In the crystal structure, a one-dimensional chain is formed by abundant hydrogen bond interactions. The interaction of the complex with DNA was monitored using agarose gel electrophoresis. The result shows that the complex can transform the supercoiled to nicked and liner forms, and has a concentration-dependent cleavage activity.展开更多
The cleavage of DNA （pBR322） by [Cu（Dime-biim）2（H2O）]（ClO4）2 （Dime-biim=1, 1＇- dimethyl-2, 2＇-biimidazole） was investigated. The results showed that the complex could cleave DNA efficiently at pH=8.0 and 3...The cleavage of DNA （pBR322） by [Cu（Dime-biim）2（H2O）]（ClO4）2 （Dime-biim=1, 1＇- dimethyl-2, 2＇-biimidazole） was investigated. The results showed that the complex could cleave DNA efficiently at pH=8.0 and 37℃.展开更多
The cleavage activity of complexes between copper (Ⅱ) and four different amino acidor amino acid methyl ester on DNA was tested at physioloical pH and temperature., It was found that Cu (Ⅱ)-L-His and Cu (Ⅱ)-L-His m...The cleavage activity of complexes between copper (Ⅱ) and four different amino acidor amino acid methyl ester on DNA was tested at physioloical pH and temperature., It was found that Cu (Ⅱ)-L-His and Cu (Ⅱ)-L-His methyl ester complexes could cleane DNA. The extent ofDNA cleavage is largely dependent on the metal ion-to-ligand ratio. The cleavage of doublestranded DNA mediated by Cu (Ⅱ)-L-His complexes occurs via a hydrolytie mechanism.展开更多
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 copper-bispyridylpyrrolide complex [Cu(PDPH)Cl](PDPH = 2,5-bis(2′-pyridyl)pyrrole) was synthesized and characterized. The complex crystallizes in the orthorhombic system with space group Pccn, a = 0.9016(3) nm, b =...A copper-bispyridylpyrrolide complex [Cu(PDPH)Cl](PDPH = 2,5-bis(2′-pyridyl)pyrrole) was synthesized and characterized. The complex crystallizes in the orthorhombic system with space group Pccn, a = 0.9016(3) nm, b = 1.0931(4) nm, c =2.5319(8) nm, and V = 2.4951(15) nm3. The copper center is situated in a square planar geometry. The interaction of the copper(II)complex with calf thymus DNA(CT-DNA) was investigated by electronic absorption, circular dichroism(CD) and fluorescence spectra. It is proposed that the complex binds to CT-DNA through groove binding mode. Nuclease activity of the complex was also studied by gel electrophoresis method. The complex can efficiently cleave supercoiled p BR322 DNA in the presence of ascorbate(H2A) via oxidative pathway. The preliminary mechanism of DNA cleavage by the complex with different inhibiting reagents indicates that the hydroxyl radicals were involved as the active species in the DNA cleavage process.展开更多
Cleavage of DNA pUC19 by [Cu(saldien)(NH3)]Cl2 (here, saldien=bis(salicylicdene)- diethylenetriamine) was investigated at different pHs, times, concentrations, and 37℃. It was found that the copper(Ⅱ) complex coul...Cleavage of DNA pUC19 by [Cu(saldien)(NH3)]Cl2 (here, saldien=bis(salicylicdene)- diethylenetriamine) was investigated at different pHs, times, concentrations, and 37℃. It was found that the copper(Ⅱ) complex could cleave DNA without added coreactants.展开更多
A dinuclear copper（Ⅱ） complex[Cu2（TATP）2（L-Leu）2（CIO4）2]2·2H2Owas synthesized and characterized, where, TATP=1,4,8,9-tetraazatriphenylene, and L-Leu=L-leucinate. The complex was crystallized in the tricl...A dinuclear copper（Ⅱ） complex[Cu2（TATP）2（L-Leu）2（CIO4）2]2·2H2Owas synthesized and characterized, where, TATP=1,4,8,9-tetraazatriphenylene, and L-Leu=L-leucinate. The complex was crystallized in the triclinic space group P1, with two independent molecules in a unit cell. Two Cu（Ⅱ） ions in each complex [Cu2（TATP）2（L-Leu）2（CIO4）2] molecule were found to be in different coordination geometries, i.e., Cu2 or Cu4 of a distorted square-pyramidal geometry coordinated with two nitrogens of TATP, the amino nitrogen and one carboxylate oxygen of L-Leu and one oxygen of perchlorate, and Cul or Cu3 with an octahedral geometry coordinated with the above stated similar coordinated atoms, and another carboxylate oxygen of L-Leu coordinating to Cu2 or Cu4. The complex can interact with CT-DNA by an intercalative mode and cleave pBR322 DNA in the presence of ascorbate.展开更多
A new asymmetric bidentate copper（Ⅱ） complex,CuL 2（HL=2-（（E）-（4-bromophenylimino）methyl）-6-bromo-4-chlorophenol）,has been synthesized and characterized by elemental analyses and single-crystal X-ray diffrac...A new asymmetric bidentate copper（Ⅱ） complex,CuL 2（HL=2-（（E）-（4-bromophenylimino）methyl）-6-bromo-4-chlorophenol）,has been synthesized and characterized by elemental analyses and single-crystal X-ray diffraction.The complex crystallizes in the monoclinic space group P2 1 /c with a=11.218（3）,b=9.355（3）,c=13.449（4）,β=108.722（4）°,V=1336.8（6）3,Z=2,Dc=2.008 g/cm 3,μ（MoKα）=7.024 mm-1,F（000）=806,S=0.999,the final R=0.0342 and wR=0.0641for2611observed reflections （I〉2σ（I））.The central copper（Ⅱ） is four-coordinate and bonds to two nitrogen and two oxygen atoms from two Schiff base ligands.The complex is linked into a two-dimensional supramolecular structure by weak intermolecular interactions.In addition,DNA-binding properties of the metal complex were investigated using spectrometric titrations and viscosity measurements.The results show that the complex binds with calf-thymus DNA（CT-DNA）,presumably via a partial intercalative mode.The intrinsic binding constant of the Cu（Ⅱ） complex with DNA is 7.335×10 3 M-1.展开更多
The crystal structure of ([CuL(H_2O)_2](ClO_4)_2·2H_2O, CuL)(L=N-(5-sulfosalicylidene)-4′-bromoaniline) was determined by means of X-ray crystallography. The interaction between CuL and salmon sperm DNA in a 0.1...The crystal structure of ([CuL(H_2O)_2](ClO_4)_2·2H_2O, CuL)(L=N-(5-sulfosalicylidene)-4′-bromoaniline) was determined by means of X-ray crystallography. The interaction between CuL and salmon sperm DNA in a 0.1 mol/L HOAc-NaOAc buffer solution(pH 5.10) was investigated by cyclic voltammetry and UV-Vis spectroscopy. A couple of redox peaks of CuL in the cyclic voltammograms(CV) can be seen at the glassy carbon electrode. It was found that the peak current of CuL decreased significantly with a negative shift of the peak potential in the presence of DNA compared with that in the absence of DNA. In addition, the decreased absorbance of CuL was observed with increasing the concentration of DNA; the absorption spectrum of an ethidium bromide(EB)-DNA system in the presence of CuL confirms that the binding mode of CuL to DNA is different from the intercalation of EB with DNA. All the experimental results indicate that CuL can bind to DNA by electrostatic binding and form a 1∶1 association complex with a binding constant of 2.72×10 4 L/mol.展开更多
A novel copper（Ⅱ） complex derived from 1,4,7-triazacyclononane[CuL]_2（PF_6）_3×MeCN×H_2 O was synthesized and crystallographically characterized {L = 1,4-bis（2-carbamoylethyl）-7-benzimidazole-2-yl-meth...A novel copper（Ⅱ） complex derived from 1,4,7-triazacyclononane[CuL]_2（PF_6）_3×MeCN×H_2 O was synthesized and crystallographically characterized {L = 1,4-bis（2-carbamoylethyl）-7-benzimidazole-2-yl-methyl-1,4,7-triazacyclononane}. It crystallizes in triclinic, space group P1, with a = 13.2425（13）, b = 14.0807（15）, c = 17.6798（18）, α = 86.296（2）, β = 72.773（2）, γ= 68.905（2）o, V = 2934.5（5）A^3, Z = 2, D_c = 1.611 g/m^3, F（000） = 1456, M_r = 1423.09, m = 0.920 mm^-1. The final R = 0.0671 and wR = 0.1874 for 6501 observed reflections with I 〉 2σ（I）. The structural analysis shows that the complex cation（[CuL]_2^3＋） was formed by two complex cations, namely（[CuL^3]^2＋） and [CuL_（-H）~3]~＋） through a hydrogen bond. In each complex cation, the Cu（Ⅱ） lies in a distorted square pyramidal geometry. The redox behavior was studied by cyclic voltammetry（CV） in aqueous solution which indicates a reversible one electron redox reaction. The result of UV absorption, ethidium bromide（EB） fluorescence spectra indicated that the complex binds to CT-DNA in an intercalative mode. Superoxide dismutase（SOD） activity of the complex was determined by photoreduction of NBT, and the value of IC_（50） is 5.22 μmol·L^-1.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
基金Young Science Foundation of Shanxi Province (No.20001005).
文摘Copper (II) complex derived from 2, 2'-pyridil ligand has been, demonstrated to cleave efficiently DNA at micromolar concentrations at room temperature and pH 7.25.
基金Supported by the National Natural Science Foundation of China (No. 20871097)the Foundation of the Innovative Group of the Education Department of Hubei Province (No. T200802)the Natural Science Foundation of the Science & Technology Department of Hubei Province (No. 2008CDB022)
文摘The reaction of N-tosylatirdine with 1,2-diaminopropane in dry benzene solution yields an intermediate H2L, N,N,N＇,N＇-tetrakis（2-（p-tolylsulfonyl）aminoethyl） propane-1,2-diamine. The mononuclear copper（Ⅱ） complex, [CuLH2O]·H2O, was synthesized by the reaction between the intermediate and copper（Ⅱ） in absolute methanol. The complex has been characterized by IR, UV-vis and X-ray diffraction technology, and its crystal crystallizes in the orthorhombic system, space group Pbca with a = 15.589（1）, b = 21.897（2）, c = 27.645（2） A, V = 9436.4（1）A^3, Dc = 1.352 g/cm^3, Z = 8, Mr = 960.68, F（000） = 4040, μ（MoKa） = 0.698 mm-1, S = 0.98, R = 0.0537 and wR = 0.1180 for 5804 observed reflections （I 〉 2σ（I））. In the crystal structure, a one-dimensional chain is formed by abundant hydrogen bond interactions. The interaction of the complex with DNA was monitored using agarose gel electrophoresis. The result shows that the complex can transform the supercoiled to nicked and liner forms, and has a concentration-dependent cleavage activity.
基金The authors acknowledge the support of the National Natural Science Foundation of China No.:2017 103 1)the Shanxi Provincial Natural Science Foundation for Youth(No.:20011007).
文摘The cleavage of DNA （pBR322） by [Cu（Dime-biim）2（H2O）]（ClO4）2 （Dime-biim=1, 1＇- dimethyl-2, 2＇-biimidazole） was investigated. The results showed that the complex could cleave DNA efficiently at pH=8.0 and 37℃.
文摘The cleavage activity of complexes between copper (Ⅱ) and four different amino acidor amino acid methyl ester on DNA was tested at physioloical pH and temperature., It was found that Cu (Ⅱ)-L-His and Cu (Ⅱ)-L-His methyl ester complexes could cleane DNA. The extent ofDNA cleavage is largely dependent on the metal ion-to-ligand ratio. The cleavage of doublestranded DNA mediated by Cu (Ⅱ)-L-His complexes occurs via a hydrolytie mechanism.
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.
基金Project(21001118)supported by National Natural Science Foundation of ChinaProject(12JJ3016)supported by Natural Science Foundation of Hunan Province,China
文摘A copper-bispyridylpyrrolide complex [Cu(PDPH)Cl](PDPH = 2,5-bis(2′-pyridyl)pyrrole) was synthesized and characterized. The complex crystallizes in the orthorhombic system with space group Pccn, a = 0.9016(3) nm, b = 1.0931(4) nm, c =2.5319(8) nm, and V = 2.4951(15) nm3. The copper center is situated in a square planar geometry. The interaction of the copper(II)complex with calf thymus DNA(CT-DNA) was investigated by electronic absorption, circular dichroism(CD) and fluorescence spectra. It is proposed that the complex binds to CT-DNA through groove binding mode. Nuclease activity of the complex was also studied by gel electrophoresis method. The complex can efficiently cleave supercoiled p BR322 DNA in the presence of ascorbate(H2A) via oxidative pathway. The preliminary mechanism of DNA cleavage by the complex with different inhibiting reagents indicates that the hydroxyl radicals were involved as the active species in the DNA cleavage process.
基金support of the National Natural Science Foundation of China(No:20171031)the Shanxi Provincial Natural Science Foundauon for Youth(No:20011007)
文摘Cleavage of DNA pUC19 by [Cu(saldien)(NH3)]Cl2 (here, saldien=bis(salicylicdene)- diethylenetriamine) was investigated at different pHs, times, concentrations, and 37℃. It was found that the copper(Ⅱ) complex could cleave DNA without added coreactants.
基金the Natural Science Foundation of Guangdong Province,China(No. 04105986)
文摘A dinuclear copper（Ⅱ） complex[Cu2（TATP）2（L-Leu）2（CIO4）2]2·2H2Owas synthesized and characterized, where, TATP=1,4,8,9-tetraazatriphenylene, and L-Leu=L-leucinate. The complex was crystallized in the triclinic space group P1, with two independent molecules in a unit cell. Two Cu（Ⅱ） ions in each complex [Cu2（TATP）2（L-Leu）2（CIO4）2] molecule were found to be in different coordination geometries, i.e., Cu2 or Cu4 of a distorted square-pyramidal geometry coordinated with two nitrogens of TATP, the amino nitrogen and one carboxylate oxygen of L-Leu and one oxygen of perchlorate, and Cul or Cu3 with an octahedral geometry coordinated with the above stated similar coordinated atoms, and another carboxylate oxygen of L-Leu coordinating to Cu2 or Cu4. The complex can interact with CT-DNA by an intercalative mode and cleave pBR322 DNA in the presence of ascorbate.
文摘A new asymmetric bidentate copper（Ⅱ） complex,CuL 2（HL=2-（（E）-（4-bromophenylimino）methyl）-6-bromo-4-chlorophenol）,has been synthesized and characterized by elemental analyses and single-crystal X-ray diffraction.The complex crystallizes in the monoclinic space group P2 1 /c with a=11.218（3）,b=9.355（3）,c=13.449（4）,β=108.722（4）°,V=1336.8（6）3,Z=2,Dc=2.008 g/cm 3,μ（MoKα）=7.024 mm-1,F（000）=806,S=0.999,the final R=0.0342 and wR=0.0641for2611observed reflections （I〉2σ（I））.The central copper（Ⅱ） is four-coordinate and bonds to two nitrogen and two oxygen atoms from two Schiff base ligands.The complex is linked into a two-dimensional supramolecular structure by weak intermolecular interactions.In addition,DNA-binding properties of the metal complex were investigated using spectrometric titrations and viscosity measurements.The results show that the complex binds with calf-thymus DNA（CT-DNA）,presumably via a partial intercalative mode.The intrinsic binding constant of the Cu（Ⅱ） complex with DNA is 7.335×10 3 M-1.
文摘The crystal structure of ([CuL(H_2O)_2](ClO_4)_2·2H_2O, CuL)(L=N-(5-sulfosalicylidene)-4′-bromoaniline) was determined by means of X-ray crystallography. The interaction between CuL and salmon sperm DNA in a 0.1 mol/L HOAc-NaOAc buffer solution(pH 5.10) was investigated by cyclic voltammetry and UV-Vis spectroscopy. A couple of redox peaks of CuL in the cyclic voltammograms(CV) can be seen at the glassy carbon electrode. It was found that the peak current of CuL decreased significantly with a negative shift of the peak potential in the presence of DNA compared with that in the absence of DNA. In addition, the decreased absorbance of CuL was observed with increasing the concentration of DNA; the absorption spectrum of an ethidium bromide(EB)-DNA system in the presence of CuL confirms that the binding mode of CuL to DNA is different from the intercalation of EB with DNA. All the experimental results indicate that CuL can bind to DNA by electrostatic binding and form a 1∶1 association complex with a binding constant of 2.72×10 4 L/mol.
基金supported by the Natural Science Foundation of Hubei Province(2014CFB410)
文摘A novel copper（Ⅱ） complex derived from 1,4,7-triazacyclononane[CuL]_2（PF_6）_3×MeCN×H_2 O was synthesized and crystallographically characterized {L = 1,4-bis（2-carbamoylethyl）-7-benzimidazole-2-yl-methyl-1,4,7-triazacyclononane}. It crystallizes in triclinic, space group P1, with a = 13.2425（13）, b = 14.0807（15）, c = 17.6798（18）, α = 86.296（2）, β = 72.773（2）, γ= 68.905（2）o, V = 2934.5（5）A^3, Z = 2, D_c = 1.611 g/m^3, F（000） = 1456, M_r = 1423.09, m = 0.920 mm^-1. The final R = 0.0671 and wR = 0.1874 for 6501 observed reflections with I 〉 2σ（I）. The structural analysis shows that the complex cation（[CuL]_2^3＋） was formed by two complex cations, namely（[CuL^3]^2＋） and [CuL_（-H）~3]~＋） through a hydrogen bond. In each complex cation, the Cu（Ⅱ） lies in a distorted square pyramidal geometry. The redox behavior was studied by cyclic voltammetry（CV） in aqueous solution which indicates a reversible one electron redox reaction. The result of UV absorption, ethidium bromide（EB） fluorescence spectra indicated that the complex binds to CT-DNA in an intercalative mode. Superoxide dismutase（SOD） activity of the complex was determined by photoreduction of NBT, and the value of IC_（50） is 5.22 μmol·L^-1.
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.
