DNA Binding and Cleavage Property of Pyrenyl-macrocyclic Polyamine Conjugate

In the past few years, there have been intensive investigations on artificial nuclease since they play a great role as a molecular tool in biochemistry1-9. Classical artificial nuclease includes two parts: DNA binding unit and chemically reactive moiety. …     

Two Novel Copper （ Ⅱ ） Complexes with A Novel Ligand 2,4-Di （2-aminopyridine）- 6-methylpyrimidine

Introduction The design and syntheses of multidentate Ndonor ligands have become the focus of much interest in the chemical field^[1-4] because these ligands can form multinuclear metal compounds, coordination polymers and supramolecular compounds, which play a very important role in the biological systems, magnetic materials, electric materials,     

Studies of a Series of Novel Rhenium（Ⅰ） Bipyridyl Dyes for Solar Cells

A series of novel rhenium(Ⅰ) 2,2‘-bipyridyl complexes [fac-Re(4,4‘-di-COOEt-bpy)-(CO)3(Xpy)PF6], where bpy is 2,2‘-bipyridine, py is pyridine and X is 3-methyl, 3-hydroxy, or 3-amino, were synthesized, their photophysical and electrochemical properties were studied. The Re(Ⅱ/Ⅰ) oxidation potentials decreased as the X group becomes more electron donating from H to 3-methyl, 3-hydroxy, or 3-amino, which might be a very convenient ways for adjusting the electron transfer driving force.     

Cleavage of DNA by a New Mixed-ligand Cu（ Ⅱ ） Complex

Cleavage of DNA pUC19 by [Cu(saldien)(NH3)]C12 (here, saldien=bis(salicylicdene)-diethylenetriamine) was investigated at different pHs, times, concentrations, and 37℃. It wasfound that the copper( Ⅱ ) complex could cleave DNA without added coreactants.     

Efficient DNA Cleavage by Copper（Ⅱ） Complex Derived from 1,1＇-Dimethyl-2,2＇-biimidazole Ligand

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℃.     

Structure, Antibacterial Activities and DNA Cleavage of a Copper（Ⅱ） Complex with 2-（2＇-Pyridyl）benzimidazole and L-Alaninate

设计合成了新的（2-（2＇-吡啶）苯并咪唑）（L-丙氨酸根）铜（II）配合物：[Cu（HPB）（L-Ala）（ClO4）（H2O）]2 H2O[HPB=2-（2＇-吡啶）苯并咪唑,L-Ala=L-丙氨酸根].应用元素分析、红外光谱、紫外可见光谱、摩尔电导率、电喷雾质谱及X射线单晶衍射等方法对配合物的组成及结构进行了表征.该配合物晶体属单斜晶系,P21空间群,晶胞参数：a=1.1900（2）nm,b=0.80500（16）nm,c=1.9700（4）nm,β=94.78（3）°,Z=2,Dc=1.672 g cm-3,F（000）=968,残差因子R1=0.0427,wR2=0.1106[I〉2σ（I）],S=0.999.在配合物分子中,2-（2＇-吡啶）苯并咪唑和L-丙氨酸根以双齿配位方式在分子平面上与中心铜（II）离子配位,而水分子及高氯酸根单齿弱配位于分子轴向上,构成了一拉长的八面体结构.利用二倍试管稀释法测定了配合物的抗菌活性,并且研究了配合物对pBR 322 DNA的断裂作用.结果表明,该配合物对枯草杆菌（B.subtilis,G＋）,金黄色葡萄球菌（S.aureus,G＋）,大肠杆菌（E.coil,G-）和沙门氏杆菌（Salmonella,G-）具有良好的抑制活性,最小抑菌浓度为50～80μg mL-1,在维生素C存在下能够通过羟基自由基OH氧化断裂pBR 322 DNA双螺旋结构.     

Characterization and Crystal Structures of Two Copper（Ⅱ） Complexes Constructed by a Flexible Double Betaine Ligand

A flexible double betaine 1,4-bis(pyridinil-4-carboxylato)-1,4-dimethylbenzene L has been used to generate two Cu(II)-containing metal complexes that exhibit different polymeric structures: [Cu(H2O)2 L]·2NO3 1 and [Cu(H2O)3 L]·2Cl·H2O 2. The crystal structures of 1 and 2 have been determined by single-crystal X-ray diffraction method. Crystal data for 1: triclinic, space group P 1, a = 5.253(2), b = 7.406(3), c = 14.792(5) , α = 84.195(5), β = 80.014(5), γ = 78.053(5)°, V = 553.2(3) 3, Z = 1, F(000) = 293, Dc = 1.717 g/cm3, the final R = 0.0385 and wR = 0.1079 for 1883 observed reflections (I > 2σ(I)); and those for 2: monoclinic, space group P21/c, a = 10.222(3), b = 25.287(7), c = 9.277(3) , β = 93.572(5)°, V = 2393.2(12) 3, Z = 4, F(000) = 1140, Dc = 1.540 g/cm3, the final R = 0.0472 and wR = 0.0956 for 3204 observed reflections (I >2σ(I)).     

A New Two-dimensional Copper（II） Complex with p-PhDTA Bridges

A new p-PhDTA bridged Cu（II） complex [Cu2（p-PhDTA）（DMSO）2]·4DMSO （p-PhDTA = p-phenylenediamine-N,N,N,N＇-tetraacetic acid） has been synthesized and structurally characterized. The crystal belongs to orthorhombic, space group Pca21 with a = 19.572（4）, b = 19.552（4）, c = 10.156（2）A, C26H48N2O14CU2S6, Mr = 932.10, V = 3886.4（13）A3, Z = 4, Dc = 1.593 g/cm^3, F（000） = 1936, λ（MoKa） = 0.71073A,μ = 1.480, R = 0.0487 and wR = 0.1151 for 8464 observed reflections （I 〉2σ（I））. In the complex, the oxygen atoms of carboxylate of p-PhDTA connect the Cu atoms in a syn-anti type, giving one-dimensional chains which are further linked by the benzene groups ofp-PhDTA to form a novel two-dimensional structure.     

Efficient Cleavage of DNA by the Novel Copper (II) Complex Derived From 2,2'-Pyridil Ligand

Due to the importance of oxidative degradation of nucleic acids in mutagenesis, carcinogenesis, and aging, a large number of chemical and biological investigations have been recently published1. Artificial metallonucleases have been proven to be efficient tools for the footprinting and sequence-specific targeting of nucleic acids1,2. They usually require high concentrations of the complex and of an external reducing agent (such as dithiothreitol, DTT) to form a reactive species in situ, the f…     

Syntheses of Binuclear Copper(I) Complexes Containing Benzimidazole

1 INTRODUCTION Procedures to synthesize copper(I) complexes are of great interest due to the diversity of products resulting from almost the same methodology. It has been long known that four-electron-donordipho- sphine compounds Ph2P(CH2)nPPh2 are excellent bi- dentate ligands[1, 2]. The chelating tendency of bis- (diphenylphosphino) methane is one of the dipho- sphine ligands most suitable to lock two metal atoms together in close proximity[3]. Many examples of bi- or polynuclear com…     

三核铜配合物[Cu_3L_2](ClO_4)_2(H_2L=1,3-双（2-羟基-1-苯基-亚甲基）-丙烷)的合成与对pBR322DNA的切断作用

利用席夫碱配体[H_2L = 1，3-双（2-羟基-1-苯基-亚甲基）-丙烷]与铜盐作 用，得到了配合物[Cu_3L_2](ClO_4)_2，并用X射线单晶衍射测定了其晶体结构。 研究了该三核铜配合物与质粒pBR322 DNA之间的相互作用，琼脂糖凝胶电泳实验结 果表明该配合物能够将pBR322 DNA从超螺旋构型切割成开环型和线型。同时，紫外 光谱实验可以推测，配合物在对pBR322 DNA进行切断时，它们之间在一种插入作用 。     

双核铜(Ⅱ)配合物在H2O2存在下对DNA的氧化切割活性

A novel dinuclear copper(Ⅱ) complex, [Cu₂(phen)(dipic)₂(H₂O)₂]·2H₂O (phen=1,10-phenanthroline, dipicH₂=2,6-pyridinedicarboxylic acid), has been prepared and structurally characterized. The complex crystallizes in the triclinic system, space group P1 with cell parameters a=0.846 0(17) nm, b=1.289 5(3) nm, c=1.452 7(3) nm, α=77.42(3)°, β=79.11(3)°, γ=87.08(3)°, and V=1.518 8(6) nm³. The dinuclear complex shows potential DNA cleavage activity at micromolar concentration in the presence of H₂O₂ and exhibits higher nuclease efficiency than mononuclear complex [Cu(dipic)(H₂dipic)]·H₂O. Without external reductants, the added H₂O₂ may contribute to the generation of hydroxyl radicals that result in DNA strand scission.CCDC:291786.     

羧酸铜与单螺旋吡啶胺配体自组装的两种新型超分子配合物

Two novel supramolecular complexes [Cu（bpapa）（dhbd）]·CHaOH （1） and [Cu（bpapa）（ma）]·ma （2） （bpapa= bis[6-（2-pyridylamino）pyrid-2-yl]amine, dhbd=2,3-dihydroxybutanedioate dianion, ma=a-methacrylate） were rationally designed, synthesized and characterized by single crystal X-ray diffraction, IR, electronic spectroscopy and thermogravimetric analyses. Complex 1 was the first oligo-a-pyfidylamino complex based on hydroxypolycarboxylate and self-assembled into a 3D honeycomb configuration network with open channels and tubes containing 1D ladder-shaped double chains formed by hydrogen bonds and aromatic π-π stacking interactions. Complex 2 constructed a 2D supramolecular network extended by 1D chains from dimeric supramolecular synthon through noncovalent supramolecular interactions. In the two complexes, the chelating monohelical ligand adopted all-anti configuration. Density functional theory calculations were applied to 1 and 2.     

Synthesis, Structure and Spectral Characterization of a Discrete Binuclear Copper (II) Complex

1　ＩＮＴＲＯＤＵＣＴＩＯＮＲｅｃｅｎｔｌｙ,ｂｒｉｄｇｅｄｂｉｎｕｃｌｅａｒｃｏｍｐｌｅｘｅｓｏｆｆｉｒｓｔｒｏｗｔｒａｎｓｉｔｉｏｎｍｅｔａｌｓｈａｖｅｒｅｃｅｉｖｅｄｍｕｃｈａｔｔｅｎｔｉｏｎｏｎａｃｃｏｕｎｔｏｆｔｈｅｉｒｂｉｏｌｏｇｉｃａｌｒｅｌｅｖａｎｃｅａｎｄｃｏｎｄｅｎｓｅｄｐｈａｓｅｍａｇｎｅｔｉｃｐｒｏｐｅｒｔｉｅｓ[1,2].Ｉｎｔｈｅｓｅｒｅｓｅａｒｃｈｅｓ,ｍａｎｙｂｒｉｄｇｅｄｌｉｇａｎｄｓｗｈｉｃｈｐｌａｙｉｍｐｏｒｔａｎｔｒｏｌｅｓｈａｖｅｂｅｅｎｕｓｅｄａｓｕｓｅｆｕｌ…     

缬氨酸Schiff碱金属铜配合物对质粒DNA的切割作用

缬氨酸Schiff碱金属铜配合物(PBP-L-Val-Cu)是新合成的一类非酶类切割工具, 合成了4种类型样品分别为L-CH3 Cu, D-CH3 Cu, L-Ph Cu和D-Ph Cu. 以质粒DNA(pUC18)为材料,分别对这4种类型化合物进行核酸切割效率的研究, 得出适合的反应体系后, 通过琼脂糖凝胶电泳对反应不同时间后核酸切割产物进行检测, 最终分别得到每种化合物将超螺旋型DNA切割成为开环型DNA和直线型DNA的切割效率, 经比较得出L-CH3 Cu型的切割效率是最快的. 将直线型DNA切割产物用琼脂糖凝胶回收试剂盒进行回收, 得到的直线型切割产物可以在T4连接酶的作用下重新连接起来. 利用酶切法对切口进行检测, 结果表明, 切割作用是具有特异性的. 另外, 该化合物对质粒pNQ216也具有切割活性.     

Ho(III)希夫碱大环配合物的合成、晶体结构及对DNA的切割活性

本文合成一个新的希夫碱大环配体硝酸Ho(III)配合物 [Ho(H2L)(NO3)2](NO3) (H2L表示大环配体Fig. 1),并进行了系统的物理表征. 晶体结构研究表明: 配合物晶体结构属六方晶系,P 3(1)21空间群,晶胞参数a=1.47213(7) nm,c=2.8998(3) nm,α=90°,γ=120°,V=5.4424(7) nm 3,Z=6,R＝0.0331, wR＝0.0928。中心离子Ho3+位于隔室大环配体的一侧并于希夫碱大环上的两个酚基氧原子和三个氮原子配位,两个双齿配位硝酸根分别从希夫碱大环平面的两侧与中心离子配位使中心离子形成扭曲的九配位三冠三棱柱配位构型。并通过凝胶电泳实验初步研究了该配合物对pBR322质粒DNA的切割作用。     

Cytotoxic copper(II) complex of tripyridoquinoxaline with DNA hydrolase activity

A monomeric copper(II) complex, [Cu(tpq)₂(H₂O)₂](ClO₄)₂, (tpq = tripyridoquinoxaline), has been synthesized and characterized spectroscopically. This complex has been found to bind DNA intercalatively and the DNA binding constant, K_b, for this complex has been determined from absorption measurements and was found to be (5.7 ± 0.3) × 10³ M⁻¹. This complex successfully promotes hydrolytic cleavage of plasmid DNA, producing single and double DNA strand breaks in the absence of any added cofactor. The amount of conversion of the supercoiled form of plasmid to the nicked circular form depends on the concentration of the copper complex as well as the duration of the incubation of the complex with DNA. The rate of conversion of SC to NC has been determined to be 2.65 × 10⁻⁴ s⁻¹ at pH 7.2 in the presence of 80 μM of the complex. This complex has also been shown to be cytotoxic towards A549 lung adenocarcinoma cells. This complex has been shown to bring about apoptosis of the cancerous A549 cell line.