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1.
四核铁配合物[Fe4(NTB)42-O)24-Suc)](ClO4)6与DNA具有较强的结合作用,结合常数kb达(5.9±0.4)×105 L·mol-1。该多核铁配合物由水解途径促进DNA断裂,在酸性及低离子浓度条件下的促进作用较为显著。动力学分析表明DNA水解没有明显的序列选择性,质粒DNA从超螺旋转变为切口形式符合饱和酶动力学规律,饱和速率常数ksat=0.014 min-1。  相似文献   

2.
The title compound was synthesized by reaction of Cu(ClO4)2, picolinic acid and carbamide in C2H5OH/CH3CN solution, and characterized by single-crystal X-ray diffraction. It crystallizes in the orthorhombic system, space group Pbca with a=14.0481(8), b=9.0130(5), c=18.626(1)?, V=2358.3(2)?3Z=4, Dx=1.771g·cm-3, μ=1.235mm-1 and F(000)=1276. The final R factor is 0.0440 for 1434 observed reflections. The X-ray analysis revealed that the copper(Ⅱ) atom is coordinated by two picolinic ligands in the equatorial plane, while the two oxygen atoms of perchlorate occupy the axial positions of octahedron with lengthened Cu-O distances, resulting in a 4+2 elongated octahedral environment. In the compound, there also exist two protonated carbamide cations for charge balance. CCDC: 195354.  相似文献   

3.
Oxo/hydoxo zirconium(IV) complex of the general formula [Zr63-O)43-OH)4(OOCCH2tBu)92-OH)3]2 has been isolated, when Zr(OiPr)4 reacted with a 2-fold excess of 3,3-dimethylbutyric acid. Single crystal X-ray diffraction data, collected at 103 and 153 K, showed that the studied compound crystallizes in hexagonal system (P63/m (no. 176)). Structure consists of dimers composed of [Zr63-O)43-OH)4(OOCCH2tBu)9] sub-units, linked by six μ2-OH bridges. Infrared spectroscopic studies proved the presence of hydroxo groups in the structure of studied clusters and formation of different types of oxo/hydroxo bridges. The application of variable temperature infrared spectroscopy and differential scanning calorimetry revealed that the structure of this complex undergoes the phase transitions at 143–183 and 203–293 K. Comparison of spectral and crystallographic data suggests that these phase transitions might be related to changes in the strength of Zr–O bonds of μ2-OH bridges linking complex sub-units, and change in symmetry of the crystal lattice (from hexagonal to trigonal). Analysis of thermogravimetric data showed that decomposition of [Zr63-O)43-OH)4(OOCCH2tBu)92-OH)3]2 proceeds with complete conversion to ZrO2 (monoclinic form) between 603 and 803 K.  相似文献   

4.
The mixed-valence manganese(Ⅲ/Ⅳ) complex [Mn2(cyclen)2(μ-O)2](ClO4)3-4H2O (1) (cyclen=1,4,7,10-tetraazacyclododecan) with chemical formula C16H48Cl3Mn2N8O18 has been synthesized and characterized by single crystal X-ray diffraction analysis, elemental analysis, IR and electronic spectra. The results showed that the manganese(Ⅲ/Ⅳ) ions were six-coordinated by four nitrogen atoms from cyclen and two oxygen atoms from the oxygen bridge, forming a distorted octahedron geometry. There were two very strong peaks in the range of 400-700 nm in electronic spectrum, which was similar to Mn catalase and Mn ribonucleotide reductase extracted from organisms.Electrochemical study indicated that the complex underwent a quasi-reversible one-electron reduction and oxidation at E1/2=0.827 V in acetonitrile.  相似文献   

5.
A new polymer azido-bridged copper(II) complex [Cu4(En)21,1-N3)41,1,1-N3)21,3-N3)2] n (I) (En = ethylenediamine) has been synthesized and crystallography characterized. Complex I shows one-dimensional coordination polymeric structure based on a tetranuclear cluster unit [Cu4(En)21,1-N3)41,1,1-N3)21,3-N3)2], in which the azido ions display three different bridging modes.  相似文献   

6.
7.
利用微波技术合成了配合物[Gd2(Gly)6(H2O)4](ClO4)6(H2O)5, 进行了化学成分分析、红外表征和热重分析. 应用X衍射仪测定其晶体结构, 该晶体为一维链结构, 属三斜晶系, P 空间群, 晶胞参数: a=1.1569(17) nm, b=1.4138(2) nm, c=1.5642(2) nm, α=96.910(2)°, β=102.735(2)°, γ=105.512(2)°, V=2.3606(6) nm3, Z=2, Dc=2.144 g•cm-3. 采用精密溶解-反应量热计, 通过设计热化学循环, 计算出了该配合物的标准摩尔生成焓为 -(7960.73±3.23) kJ•mol-1.  相似文献   

8.
[Cd(CHZ)3](ClO4)2的制备和分子结构研究   总被引:10,自引:0,他引:10  
本文报道了高氯酸三碳酰肼合镉(Ⅱ)的制备方法和分子结构。该配合物结构式为[Cd(CHZ)3](ClO4)2。晶体属单斜晶系,P21/n空间群。晶体学参数为:a=1.0281(1) nm, b=0.8617(1) nm, c=2.1360(1) nm,β=100.53°, V=1.8604(3) nm3; Z=4, Dc=2.076 g·cm-3, μ(Mo, Kα)=15.43 cm-1。经全矩最小二乘法对非氢原子坐标和温度因子进行修正。最终偏离因子R=0.0296。在该配合物中,碳酰肼(CHZ)分子作为双齿配体,由羰基氧原子和1位氮原子与Cd配位,形成五员平面螯合环,配合物分子中共有三个这样的螯合环,中心离子为六配位八面体构型;配合物的外界是两个高氯酸根离子,通过库仑力与内界结合在一起。  相似文献   

9.
10.
[Mn3O(O2CCH2Cl)6(C5H5N)2(H2O)]·CH2ClCOO·H2O在pH=4.5的HOAcNaOAc的缓冲水溶液中和2,2′联吡啶(bipy)反应,制得了混合价双核锰配合物[(bipy)2Mn(μ-O)2Mn(bipy)2](ClO4)3·1.5H2O。该配位化合物的X射线单晶衍射表明,该晶体属单斜晶系,空间群P21/c,晶胞参数:a=1.3854(3),b=1.3943(3),c=2.4225(5)nm,β=103.30°,V=4.554(2)nm3,Z=4,Dc=1.448g·cm-3。其紫外可见光谱在640nm处有一个峰,可指派为桥配体O2-到Mn(Ⅲ)的电荷迁移光谱.循环伏安实验说明,此配合物在半波电位E1/2为1.25V处,有一个可逆的氧化还原峰,这相应于(Ⅲ,Ⅳ)态氧化为(Ⅳ,Ⅳ)态,另外在0.37V处有一阴极峰,相应于(Ⅲ,Ⅳ)态还原为(Ⅲ,Ⅲ)态,在0.81V处有一氧化峰,相应于(Ⅲ,Ⅲ)态氧化为(Ⅲ,Ⅳ)态,这两个峰是不可逆的。  相似文献   

11.
Reactions of [(dtc)2Mo2(S)2(μ-S)2] with one or two equivalents of CuBr in CH2Cl2 afforded two new heterobimetallic sulfide clusters, [(dtc)2Mo23-S)(μ-S)3(CuBr)] (1) and [(dtc)2Mo23-S)4(CuBr)2] (2). Both compounds were characterized by elemental analysis, IR, UV-vis and X-ray analysis. Compound 1 contains a butterfly-shaped Mo2S4Cu core in which one CuBr unit is coordinated by one bridging S and two terminal S atoms of the [(dtc)2Mo2(S)2(μ-S)2] moiety. In the structure of 2, one [(dtc)2Mo2(S)2(μ-S)2] moiety and two CuBr units are held together by six Cu-μ3-S bonds, forming a cubane-like Mo2S4Cu2 core.  相似文献   

12.
设计并合成了一个含咪唑基团的柔性双齿配体:1,3-二(咪唑基-1′-甲基)-5-甲基苯(dimb)(1),并进行了 1H NMR和结构表征。通过dimb与高氯酸钴的反应,得到了一个新型的具有二维网状结构的配合物:[Co(dimb)2(MeOH)2](ClO4)2(2)。X-射线晶体结构测定表明,这两个化合物的晶体学参数分别为:配体(1)属单斜晶系, 空间群  相似文献   

13.
Single crystals of Cs4[(UO2)2(C2O4)(SO4)2(NCS)2] · 4H2O (I) and (NH4)4[(UO2)2(C2O4)(SO4)2(NCS)2] · 6H2O (II) have been synthesized and studied by X-ray diffraction. The crystals of both compounds are orthorhombic with the space group Pbam, Z = 2, and unit cell parameters a = 12.0177(3) ?, b = 18.6182(5) ?, c = 6.7573(10) ?, R = 0.0376 (I); a = 11.6539(9) ?, b = 18.3791(13) ?, c = 6.7216(5) ?, R = 0.0179 (II). The main structural units of crystals I and II are [(UO2)2(C2O4)(SO4)2(NCS)2]4− chains belonging to the crystal-chemical group A2K02B22M21 (A = UO22+, K02 = C2O42−, B2 = SO42−, M1 = NCS) of the uranyl complexes. The uranium-containing chains are joined into a three-dimensional framework due to a system of electrostatic interactions with the cesium or ammonium ions in the structure of I. In the structure of II, this framework is additionally stabilized by hydrogen bonds involving the outer-sphere water molecules and ammonium ions. Original Russian Text ? I.V. Medrish, A.V. Virovets, E.V. Peresypkina, L.B. Serezhkina, 2008, published in Zhurnal Neorganicheskoi Khimii, 2008, Vol. 53, No. 7, pp. 1115–1120.  相似文献   

14.
Thermodynamical data of rare earth complexes with amino acid are important for engineering chemistry and fundamental chemistry. However, they have rarely been reported. In this work, a series of crystalline complexes of rare earth perchlorate coordinated with glutamic acid have been synthesized in water medium, and their thermodynamical data, including the heat capacity in low temperature range and the standard enthalpy of formation, were determined. These complexes were identified to be [RE2(Glu)2(H2O)8](ClO4)4·H2O (RE = Nd, Eu, Dy) by using thermogravimetric analysis (TG), differential thermal analysis (DTA), and chemical and elementary analyses. Their purity has been determined. No melting points were observed for all the three complexes. The heat capacity of the complexes was measured by an adiabatic calorimeter from 79 to 370 K. Abnormal heat capacity values were detected for two of the complexes and the decomposition range of one complex was found. The temperature, enthalpy change and entropy change of the decomposition processes of the three complexes were calculated. The polynomial equations of heat capacity in the experimental temperature range have been obtained by least squares fitting. The standard enthalpy of formation was determined by an isoperibol reaction calorimeter at 298.15 K. Supported by the Research Fund of Beijing Institute of Petro-Chemical Technology (N06-06)  相似文献   

15.
The synthesis and spectroscopic properties of a Na complex with ligand 3-aminopyrazine-2-carboxylic acid were described. The resulting complex was characterized by elemental analysis, IR, UV-Vis, NMR spectroscopy and single crystal X-ray diffraction method. The title compound crystallizes in the triclinic system with space group . The crystalline structure of this compound consists of supramolecular architectures involving strong intramolecular N—H…O in pyrazine molecules and intermolecular O—H…N, O—H…O, and N—H…N hydrogen bonds between substituted pyrazine and water molecules.  相似文献   

16.
The product of the thermal reaction between cobalt acetate hydrate and benzoic acid reacts with a triethylamine excess to form the trinuclear complex Co3(μ-OOCPh)4(μ,η2-OOCPh)2[OC(Ph)OHNEt3]2, and its reaction with 3,5-dimethylpyrazole yields the mononuclear complex Co(Hdmpz)2(OOCPh)2. The compound structures are discussed on the basis of X-ray crystallographic data.  相似文献   

17.
合成了希土高氯酸盐开环冠醚二缩乙二醇(EO2)晶体,(Ln=Nd, Ho),测定了结构,文内以Nd-L的数据为主要研究对象(方括号内是Ho-L的数据)。晶体属单斜晶系,P21/n空间群,化学式[Ln(EO2)3](ClO4)3·3H2O,晶胞参数为:a=14.124(1)[14.087], b=13.990(1)[14.039], c=15.265(1)[15.014]?; β=95.78(1)[95.64]°; V=3001.1(6)[2955]?3; Mr=815.01[835.70]; Z=4; Dc=1.804[1.865]g/cm3;石墨单色器,μ(MoKα)=2.09[3.07] mm-1,最终偏离因子R=0.055[0.074], RW=0.071[0.109]。研究结果表明晶体具有相同的结构,配位多面体为九配位三帽三棱柱。发现EO2醚链有绕C-C键呈STT分布的规律。弱配体高氯酸根不参加配位。  相似文献   

18.

Abstract  

Reaction of the [Me4N]2[Cd(SPh-4-Me)4] with two equivalents of [M(PPh3)2NO3] afforded the neutral linear trinuclear complexes [Cd(μ-SPh-4-Me)4{M(PPh3)2}2] (M = Cu 1, Ag 2) in which two [M(PPh3)2]+ fragments chelate with the opposite edges of a tetrahedral [Cd(SPh-4-Me)4]2− moiety via the sulfur atoms of the Me-4-PhS species. Treatment of [Sn(SPh)4] with two equivalents of [Ag(PPh3)2NO3] gave the neutral linear trinuclear complex [Sn(μ-SPh)6(AgPPh3)2] (3) that is composed of a central distorted SnS6 octahedron sharing two opposite planes with two slightly distorted AgS3P tetrahedrons. Complexes 2 and 3 are air and optically stable. Their nonlinear optical absorption and refraction were investigated under the same conditions. The nonlinear optical absorption and refraction of complex 2 were determined to be α 2 = 3.11 × 10−11 m/W and n 2 = 4.15 × 10−12 esu, respectively. The nonlinear optical absorption and refraction of complex 3 were determined to be α 2 = 8.36 × 10−11 m/W and n 2 = 1.47 × 10−11 esu, respectively.  相似文献   

19.
合成了一种稀土高氯酸盐-谷氨酸配合物. 经TG/DTG、化学和元素分析、FTIR及与相关文献对比, 确定其组成为[Pr2(L-α-Glu)2(ClO4)(H2O)7](ClO4)3•4H2O, 纯度为99.0%以上. 利用显微熔点仪分析发现其没有熔点. 在78~370 K温区, 用精密绝热量热仪测量其低温热容, 在285~306 K温区发现一明显吸热峰, 归结为固-固相变过程. 通过相变温区三次重复热容测量, 得到相变温度Ttr、相变焓ΔtrHm和相变熵ΔtrSm分别为(297.158±0.280) K, (12.338±0.016) kJ•mol-1和(41.520±0.156) J•K-1•mol-1. 用最小二乘法将非相变温区的热容对温度进行拟合, 得到了热容随温度变化的两个多项式方程. 用此方程进行数值积分, 得到每隔5 K的舒平热容值和相对于273.15 K的热力学函数值. 根据TG/DTG结果, 推测了该配合物的热分解机理. 依据Hess定律, 选择1 mol•dm-3盐酸为量热溶剂, 利用等温环境溶解-反应量热计, 测定了该配合物的标准摩尔生成焓为: ΔfHm0=-(7223.1±2.4) kJ•mol-1.  相似文献   

20.
A new heteronuclear germanium barium complex with D-tartaric acid [Ba(H2O)4][Ge2(μ-Tart)2(μ-OH)2]·5H2O (I) (H4Tart is tartaric acid) was synthesized. The identity of compound I and its com- position were determined by elemental analysis and X-ray diffraction. The thermal stability of the compound was studied; the coordination centers of the ligand were found from IR spectroscopy. The structure of I was determined by X-ray crystallography. Crystals I are tetragonal: a = 8.5033(2) ?, c = 30.9393(11) ?, V = 2237.10(11) ?3, Z = 4, space group P41, R1 = 0.0301 based on 4215 reflections with I > 2σ(I). In crystals I, neutral [Ge2(μ-Tart)2] dimers are linked in pairs by double hydroxyl bridges to form {[Ge2(μ-Tart)2(μ-OH)2]2−} polymeric chains. Hydrated Ba2+ cations and crystal water molecules are in between the anionic chains. Polymeric complex anions, hydrated barium cations, and H2O molecules are bound by a system of hydrogen bonds to form a framework.  相似文献   

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