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1.
采用动力学研究方法测定了手性金属配合物d-[Co(EDTA)]^-和ι-[Co(EDTA)]^-跨Caco-2细胞单层的转运速率。研究发现,由于金属配合物的手性差异,导致d-[Co(EDTA)]^-和ι-[Co(EDTA)]^-经Caco-2细胞单层的转运速率明显不同;手性金属配合物经Caco-2细胞单层转运吸收时存在手性选择性,表明小肠对手性金属配合物药物可能有选择性吸收;d-[Co(EDTA)]^-和ι-[Co(EDTA)]^-经Caco-2细胞单层的转运依赖浓度梯度驱动,说明该对映体配合物经Caco-2细胞单层转运吸收时存在简单扩散的转运方式。  相似文献   

2.
用高效液相色谱(HPLC)法测定了水溶液中碱催化下异构体-(差向立体异构体):Δ(S)∧(R)和Δ(R)∧(S)-[Co(tp)2(Me3-en)]ClO4(tp:2-羟基-2,4,6-环庚三烯-1-酮负离子;Me3-en:N,N,N'-三甲基乙二胺)手性配位氮的翻转(差向立体异构体)速率常数kep(34.0 ℃),研究结果发现,碱催化下手性配位氮的翻转作用具有二级反应动力学方程:v=kep[配合物][OH^-],[Co(tp)2(Me3-en)]ClO4的kep值比[Co(tp)2(Me3-en)]ClO4的kep值大一个数量级,Δ(R)∧(S)-异构体比Δ(S)∧(R)-异构体具有更大的手性配位氮翻转速率。  相似文献   

3.
针对国际上对金属配合物同DNA间作用机量的争议,采用分子模拟手段在MM2力场下,搭建并优化了手性金属配合物△,Λ-[Co(phen)2tpphz]^3+与B-DNA[d(GTCGATCGAC)2]的模型,继而对其相互作用进行了模拟,得出的结论是:对所采用的B-DNA片断,该金属配合物有明显的立体选择性△型配合物从小沟插入占明显优势,而且,总体来看,从AT区插入更易进行。  相似文献   

4.
马桂林  黄明昌 《化学学报》1992,50(3):262-268
本文合成了[Co(tp)~2(Me-en)]ClO~4(tp:2-羟基-2,4,6-环庚三烯-1-酮负离子;Me-en:N-甲基乙二胺)三元不对称配合物, 用离子交换法分离了该配合物的Λ(R)△(S)和Λ(S)△(R)两对对映体, 用高效液相色谱法测定了对映体的不对称配位氮的翻转速率常数k~e~p(差向立体异构化速率常数), 用^1HNMR法测定了对映体的不对称配位氮的重氢化质子交换)速率常数k~D, 并与同属CoO~4~2型的Na[Co(OX)~2(Me-en)](OX:草酸根)、[Co(acac)~2(Me-en)]ClO~4(acac:2,4-戊二酮负离子)配合物的k~e~p、k~D值进行了比较, 讨论了影响质子交换、不对称氮翻转速率的因素及反应机理。  相似文献   

5.
本文合成了[Co(tp)_2(Me-en)]ClO_4(tp:2-羟基-2,4,6-环庚三烯-1-酮负离子;Me-en:N-甲基乙二胺)三元不对称配合物,用离子交换法分离了该配合物的Λ(R)Δ(S)和Λ(S)Δ(R)两对对映体,用高效液相色谱法测定了对映体的不对称配位氮的翻转速率常数K_(ep)(差向立体异构化速率常数),用~1HNMR法测定了对映体的不对称配位氮的重氢化(质子交换)速率常数k_D,并与同属CoO_4N_2型的Na[Co(OX)_2(Me-en)](OX:草酸根)、[Co(acac)_2(Me-en)]ClO_4(acac:2,4-戊二酮负离子)配合物的k_(ep)、k_D值进行了比较,讨论了影响质子交换、不对称氮翻转速率的因素及反应机理。  相似文献   

6.
杨频  熊振海 《化学学报》2001,59(7):1038-1044
针对国际上对金属配合物同DNA间作用机量的争议,采用分子模拟手段在MM2力场下,搭建并优化了手性金属配合物△,Λ-[Co(phen)2tpphz]^3+与B-DNA[d(GTCGATCGAC)2]的模型,继而对其相互作用进行了模拟,得出的结论是:对所采用的B-DNA片断,该金属配合物有明显的立体选择性△型配合物从小沟插入占明显优势,而且,总体来看,从AT区插入更易进行。  相似文献   

7.
过渡金属硫配合物可作为加氢脱硫(HDS)和加氢脱氮(HDN)过程的有效催化剂而倍受人们关注[1-3].这类配合物的催化活性、选择性和抗毒性与过渡金属的种类、配合物本身的立体结构和电子分布密切相关[4-5].其中,钴的硫化物在HDS和HDN过程中有很好的催化活性.本文由二元金属羰合物Co2(CO)8和双(硫代磷酸二异丙基酯)二硫化物(A),合成标题配合物Co[S2P(O-i-C3H7)2]3 (B),对配合物B进行XRD表征,并对反应机理进行初步探讨.反应式如下:  相似文献   

8.
研究了4种不同电荷的Co(Ⅲ)金属配合物跨人红细胞膜的动力学,并测定了它们跨人红细胞膜的一级反应动力学速率常数,发现[Co(C2O4)3]3-的跨膜速率明显高于[Co(en)3]3+,[Co(en)2(C2O4)]+和[Co(en)(C2O4)2]-,后3种配合物的跨膜速率常数随正电荷的减少略有增加,跨膜机制为简单扩散.[Co(C2O4)3]3-的跨膜速率受阴离子通道抑制剂DIDS明显抑制,抑制率为51.95%,推测其跨膜机制为部分经阴离子通道协同简单扩散过膜.人红细胞摄入L-[Co(C2O4)3]3-的速率明显大于D-[Co(C2O4)3]3-,显示了一定的手性选择性.  相似文献   

9.
描述了两个具有管状氢键假想孔道结构的化合物[Ni(en)3][GeF6][JLG-1(Ni)]和[Co(en)3].[GeF6][JLG-1(Co)].在这两个结构中,[GeF6]2-阴离子与手性金属配合物阳离子[M(en)3]2+(M=Ni,Co)通过F…N之间复杂的弱氢键相互作用,在沿着63螺旋轴方向形成六方蜂窝状排布的管状氢键假想孔道.结构研究发现,配对的[GeF6]2阴离子和手性[M(en)3]2+阳离子同属于D3点群,这是JLG-1(Ni)和JLG-1(Co)形成管状氢键假想孔道的关键.这一研究成果对设计合成氢键假想孔道体系具有一定的指导意义.  相似文献   

10.
席小莉  杨曼曼  陈绘丽  杨频 《化学学报》2010,68(14):1415-1420
为了开发能识别正常与错配核酸的探针, 首次合成了[Co(phen)2(HNAIP)]Cl3金属配合物, 并利用二维核磁研究了此配合物与错配d(CCGAATGAGG)2及正常d(CCTAATTAGG)2寡聚核苷酸的相互作用, 首次发现, [Co(phen)2(HNAIP)]Cl3是从“大沟”插入到错配碱基对G3A4和G7A8之间, 能够很好地识别G:A错配; 而[Co(phen)2(HNAIP)]Cl3与正常的寡聚核苷酸的作用, 则是从小沟插入, 即[Co(phen)2(HNAIP)]Cl3与错配和正常寡聚核苷酸在不同位置及不同沟槽存在明显的插入式结合、并且有明显的差异, 这就有可能被用来作为识别正常与错配寡聚核苷酸的探针.  相似文献   

11.
Three ligands, 2-(3-(carboxymethyl)-1,10-phenanthroline-[5,6-d]imidazole-1-yl)acetate (CPIA), 2-(benzo[d][1,3]dioxol-4-yl)-1H-imidazo[4,5-f][1,10]phenanthroline (BIP), and 2-(9H-carbazol-3-yl)-1H-imidazo[4,5-f][1,10]phenanthroline (CIP), and their complexes, [Co(phen)2(CPIA)]3+ (1) (phen = 1,10-phenanthroline), [Co(phen)2(BIP)]3+ (2), and [Co(phen)2(CIP)]3+ (3), have been synthesized and characterized. Binding of the three complexes with calf thymus DNA (CT-DNA) has been investigated by spectroscopic methods, cyclic voltammetry, and viscosity measurements. The three complexes bind to DNA through an intercalative mode, and the size and shape of the intercalative ligands have significant effects on the binding affinity of complexes to CT-DNA.  相似文献   

12.
The reaction of [Co(2)(CO)(8)] with (CF(3))(3)BCO in hexane leads to the Lewis acid-base adduct [Co(2)(CO)(7)CO--B(CF(3))(3)] in high yield. When the reaction is performed in anhydrous HF solution [Co(CO)(5)][(CF(3))(3)BF] is isolated. The product contains the first example of a homoleptic metal pentacarbonyl cation with 18 valence electrons and a trigonal-bipyramidal structure. Treatment of [Co(2)(CO)(8)] or [Co(CO)(3)NO] with NO(+) salts of weakly coordinating anions results in mixed crystals containing the [Co(CO)(5)](+)/[Co(CO)(2)(NO)(2)](+) ions or pure novel [Co(CO)(2)(NO)(2)](+) salts, respectively. This is a promising route to other new metal carbonyl nitrosyl cations or even homoleptic metal nitrosyl cations. All compounds were characterized by vibrational spectroscopy and by single-crystal X-ray diffraction.  相似文献   

13.
铅(II)-氨基多羧酸配合物的合成与结构研究   总被引:1,自引:0,他引:1  
合成了铅(II)与乙二胺四乙酸(EDTA),N-羟乙基乙二胺三乙酸(HEDTA)和 (乙酸-N-羟乙基酯)乙二胺三乙酸(AHEDTA, A = 乙酸-N-羟乙基酯)的配合物,C10H20K2N2O12Pb (K2[Pb(EDTA)]4H2O), C10H22K2N2O11Pb (K2[Pb(HEDTA)]4H2O)和C12H23KN2O11Pb (K[Pb- (AHEDTA)]3H2O), 并测定了K2[Pb(EDTA)]4H2O晶体结构和分子结构。具体测定结果如下:单斜晶系,C2/c空间群,a = 24.59(2),b = 11.79(1),c = 14.08(2) 牛琤 = 108.15(2),V = 3876.0(7)) 3,Z = 8,Mr = 654.65,Dc = 2.213 g/cm3,m = 9.196 mm-1和F(000) = 2480。最终偏差因子分别为R = 0.0458,wR = 0.0640 (对3372 (I > 2.0s(I))可观测衍射点)。在K2[Pb(EDTA)]4H2O中,配合物离子[Pb(EDTA)]2-具有六配位的非标准三棱柱体结构,EDTA作为六齿配体提供4个O原子和2个N原子与中心金属离子Pb2+形成配键。  相似文献   

14.
Two kinds of tris(beta-diketonato) metal(III) complexes denoted as [M(acac)2(LC12)] and [M(acac)2(Lazo)] (M=Ru(III) and Co(III); acac=acetylacetonato; LC12=1,3-didodecyloxyphenyl-1,3-propanedionato; Lazo=3-[4'-(4'-(butoxy)phenylazo)phenyl]-pentane-2,4-dionato) were synthesized and optically resolved into Delta, Lambda isomers. Here, LC12 and Lazo were designed to be elongated perpendicular to and in parallel with the molecular C 2 axis, respectively. The metal complexes were doped into three kinds of nematic liquid crystals (MBBA, EBBA, and ZLI-1132). Both dopants induced chiral nematic phases with relatively high helical twisting powers. With a purpose to clarify the mechanisms of helical induction, order parameters (S) were determined by means of polarized UV-vis measurements on nematic samples doped with racemic Co(III) complexes. As a result, the long axes of the elongated ligands in both [Co(acac)2(LC 12)] and [Co(acac)2(trans-Lazo)] were found to align in the direction of the director vector with S=0.50+/-0.05 and 0.60+/-0.05, respectively. Based on the results, the photoresponsive behavior of Delta- or Lambda-[Ru(acac)2(Lazo)] was interpreted in terms of the variation of S accompanied with the cis-trans isomerization of the azobenzene moiety in Lazo.  相似文献   

15.
Two new octahedral [Ni(phen)2(dppz-idzo)]2+ and [Co(phen)2(dppz-idzo)]3+ complexes have been synthesized and characterized by CHN analysis, electrospray ionization-MS, nuclear magnetic resonance, and UV–Vis spectra. The DNA-binding ability of these complexes was spectrophotometrically, hydrodynamically, and electrophoretically evaluated which indicated that they strongly intercalate into the DNA double helix, and that both induced severe DNA damage in the presence of peroxide. The complexes also showed strong antiproliferative effect against HepG2 and MDA-MB-231 cells. By contrast, they were found to be inactive against the MCF-7 cell line. The ligand itself was found to be inactive against the cells tested.  相似文献   

16.
Isolation of the free bicyclic tetraamine, [3(5)]adamanzane.H(2)O (1,5,9,13-tetraazabicyclo[7.7.3]nonadecane.H(2)O), is reported along with the synthesis and characterization of a copper(II) complex of the smaller macrocycle [(2.3)(2).2(1)]adamanzane (1,5,9,12-tetraazabicyclo[7.5.2]hexadecane) and of three cobalt(II), four nickel(II), one copper(II), and two zinc(II) complexes with [3(5)]adamanzane. For nine of these compounds (2-8, 10b, and 12) the single-crystal X-ray structures were determined. The coordination geometry around the metal ion is square pyramidal in [Cu([(2.3)(2).2(1)]adz)Br]ClO(4) (2) and trigonal bipyramidal in the isostructural structures [Cu([3(5)]adz)Br]Br (3), [Ni([3(5)]adz)Cl]Cl (5), [Ni([3(5)]adz)Br]Br (6), and [Co([3(5)]adz)Cl]Cl (8). In [Ni([3(5)]adz)(NO(3))]NO(3) (4) and [Ni([3(5)]adz)(ClO(4))]ClO(4) (7) the coordination geometry around nickel(II) is a distorted octahedron with the inorganic ligands at cis positions. The coordination polyhedron around the metal ion in [Co([3(5)]adz)][ZnCl(4)] (10b) and [Zn([3(5)]adz)][ZnCl(4)] (12) is a slightly distorted tetrahedron. Anation equilibrium constants were determined spectrophotometrically for complexes 2-6 at 25 and 40 degrees C and fall in the region 2-10 M(-1) for the halide complexes and 30-65 M(-1) for the nickel(II) nitrate complex (4). Rate constants for the dissociation of the macrocyclic ligand from the metal ions in 5 M HCl were determined for complexes 2, 3, 5, 8, 10, and 12. The reaction rates vary from half-lives at 40 degrees C of 14 min for the dissociation of the Zn([3(5)]adz)(2+) complex (12) to 14-15 months for the Ni([3(5)]adz)Cl(+) ion (5).  相似文献   

17.
Yoon JH  Lim JH  Kim HC  Hong CS 《Inorganic chemistry》2006,45(24):9613-9615
Two cyanide-bridged WV-M [M = Mn(II) (1), Co(II) (2)] bimetallic clusters were prepared by self-assembling a new molecular precursor [W(CN)6(bpy)]- and the corresponding metal complexes. Compound 1 shows a tetranuclear W2Mn2 entity, consisting of a Jahn-Teller ion, Mn(III), which serves as an anisotropic source, while compound 2 exhibits a trimeric W2Co structure. Among them, compound 1 displays slow relaxation of the magnetization, which is typical of a single-molecule magnet behavior.  相似文献   

18.
The use of 2-amino-isobutyric acid in Co/Ln chemistry has led to the isolation of two unique [Co(II)(6)Ln(III)] 3d-4f metallic cages in which the Ln(III) centre (Ln = Eu, Dy) is encapsulated within a Co(II)(6) trigonal prism.  相似文献   

19.
The preparations and structures are described of four new polyoxostibonates, [Co(p-MeC(6)H(4)Sb)(12)O(28){Co(H(2)O)(3)}(4)]Cl(2)·6H(2)O, [Co(p-ClC(6)H(4)Sb)(12)O(28){Co(H(2)O)(3)}(4)]Cl(2)·22H(2)O, (PhCH(2)NMe(3))(2)[Zn(p-ClC(6)H(4)Sb)(12)O(28)Zn(4)Cl(2.54)Br(1.46)]·8MeCN·H(2)O and [BaCoH(4)(p-MeC(6)H(4)Sb)O(28)]·5H(2)O. Each of these has a framework of 12 (RSb) groups linked by 28 O atoms, with one transition metal ion in a tetrahedral site in the centre. Other metal ions are coordinated to the polyhedral faces. Three of the complexes have the ε Keggin ion geometry, while the fourth is a δ isomer.  相似文献   

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