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1.
席夫碱配体由于在合成上具有极大的灵活性和良好的配位能力 ,因而席夫碱 -金属配合物的研究一直受到广泛重视 .多年来 ,席夫碱配体由简单的单齿发展到多齿和大环配体 .此外 ,过渡金属的席夫碱配合物具有独特的结构、性能和广泛的应用 ,如氧化还原 [1] 、催化 [2 ] 以及生物体系的化学模拟 [3 ] ;另一方面 ,由于银原子配位方式的多样性 (二、三、四和五配位 ) ,便于人们对超分子化合物的组装规律进行系统研究 ,因而银配合物的研究正日益引起人们极大的兴趣 [4~ 7] .鉴于此 ,我们设计合成了一个新的四齿席夫碱配体 L ,研究了其与 CF3 SO3 …  相似文献   

2.
制备了一个双席夫碱N,N′-双(3,5-二氟亚水杨基)-1,3-二氨基丙烷(H_2L)。利用H_2L、醋酸锰和硫氰酸铵或者叠氮化钠在甲醇中反应分别制得了配合物[MnL(NCS)(OH_2)](1)和[MnL(μ_(1,3)-N_3)]_n(2)。通过元素分析、红外光谱、核磁共振氢谱对H_2L和其配合物进行了表征,用单晶X射线衍射测定了配合物的结构。席夫碱配体利用其亚胺基氮原子和酚羟基氧原子与Mn进行配位。硫氰酸根配体利用其氮原子配位,而叠氮根配体利用两端的氮原子以桥联的方式进行配位。在每个配合物中,Mn原子都采取八面体配位构型。测试了H_2L和2个配合物对刀豆脲酶的抑制活性。在浓度为100μmol·L~(-1)时,配合物1对脲酶的抑制率为(52.0±3.1)%,其IC50值为(81.0±3.7)μmol·L~(-1),而配合物2却没有活性。还利用分子对接技术研究了配合物1与脲酶的作用方式。  相似文献   

3.
以手性苯乙胺与吡啶醛缩合得到的含双齿或三齿配位基的手性席夫碱(L1、L2)为配体,合成了4对单核铁、镍手性对映体配合物fac-Λ-[M(R-L1)3](ClO4)2·3CH3CN(M=Fe,1R-Fe;M=Ni,1R-Ni),fac-Δ-[M(S-L1)3](ClO4)2·3CH3CN(M=Fe,1S-Fe;M=Ni,1S-Ni),[M(R-L2)2](ClO4)2(M=Fe,2R-Fe;M=Ni,2R-Ni),[M(S-L2)2](ClO4)2(M=Fe,2S-Fe;M=Ni,2S-Ni)。利用红外光谱(IR)、核磁共振氢谱(1H NMR)、元素分析(EA)、X-射线单晶衍射等手段对配合物结构进行了表征。对化合物1R-Fe,1R-Ni,1S-Ni,2R-Fe进行了晶体结构分析,其中1R-Fe,1R-Ni,1S-Ni结晶于P213手性空间群,金属中心与3个二齿配体(L1)提供的6个氮原子配位形成了扭曲变形的八面体结构;R型配体诱导配合物形成fac-Λ构型,而S型配体诱导配合物形成fac-Δ构型。2R-Fe结晶于P212121手性空间群,二价铁离子与2个三齿配体(R-L2)提供的6个氮原子配位形成了扭曲变形的八面体结构。利用紫外-可见吸收光谱、荧光猝灭光谱、圆二色谱等光谱分析法研究了配合物与DNA的相互作用。研究结果表明这4对手性配合物均能与小牛胸腺CT-DNA发生不同强度的结合,结合稳定常数从4.41×103 L·mol-1到1.88×104 L·mol-1。配合物与DNA的结合模式可能是通过静电作用与DNA骨架发生沟面结合。金属中心为铁的配合物表现出比相应的镍配合物更强的DNA作用力;而含三齿配体L2的配合物与DNA的作用均比相应的含二齿配体L1的配合物更强;S型配体形成的配合物与DNA的结合能力优于R型配体形成的配合物。  相似文献   

4.
以手性苯乙胺与吡啶醛缩合得到的含双齿或三齿配位基的手性席夫碱(L1、L2)为配体,合成了4对单核铁、镍手性对映体配合物fac-Λ-[M(R-L1)3](ClO4)2·3CH3CN(M=Fe,1R-Fe;M=Ni,1R-Ni),fac-Δ-[M(S-L1)3](ClO4)2·3CH3CN(M=Fe,1S-Fe;M=Ni,1S-Ni),[M(R-L2)2](ClO4)2(M=Fe,2R-Fe;M=Ni,2R-Ni),[M(S-L2)2](ClO4)2(M=Fe,2S-Fe;M=Ni,2S-Ni)。利用红外光谱(IR)、核磁共振氢谱(1H NMR)、元素分析(EA)、X-射线单晶衍射等手段对配合物结构进行了表征。对化合物1R-Fe,1R-Ni,1S-Ni,2R-Fe进行了晶体结构分析,其中1R-Fe,1R-Ni,1S-Ni结晶于P213手性空间群,金属中心与3个二齿配体(L1)提供的6个氮原子配位形成了扭曲变形的八面体结构;R型配体诱导配合物形成fac-Λ构型,而S型配体诱导配合物形成fac-Δ构型。2R-Fe结晶于P212121手性空间群,二价铁离子与2个三齿配体(R-L2)提供的6个氮原子配位形成了扭曲变形的八面体结构。利用紫外-可见吸收光谱、荧光猝灭光谱、圆二色谱等光谱分析法研究了配合物与DNA的相互作用。研究结果表明这4对手性配合物均能与小牛胸腺CT-DNA发生不同强度的结合,结合稳定常数从4.41×103 L·mol-1到1.88×104 L·mol-1。配合物与DNA的结合模式可能是通过静电作用与DNA骨架发生沟面结合。金属中心为铁的配合物表现出比相应的镍配合物更强的DNA作用力;而含三齿配体L2的配合物与DNA的作用均比相应的含二齿配体L1的配合物更强;S型配体形成的配合物与DNA的结合能力优于R型配体形成的配合物。  相似文献   

5.
合成并通过单晶衍射表征了5个配合物[Cu LCl2]·CH3COCH3(1)、[Zn LCl2]·CH3COCH3(2)、[Zn L(NO3)2]·0.5CH3COCH3(3)、[Ag L2]Cl O4(4)和[Ag L2]BF4(5)(L=2-(5-氯-8-喹啉氧基)-1-(吡咯烷-1-基)乙酮)。配合物1和2同构,五配位的中心金属离子采取扭曲的四方锥配位构型,与来自配体L的2个氧原子和1个氮原子及2个氯离子配位。而在配合物3中,锌离子与1个三齿配位的配体L,1个单齿配位的硝酸根和1个双齿配位的硝酸根配位,配位构型为扭曲的八面体。配合物4和5中,中心金属与配体的比例为1∶2。银离子与2个三齿配位的配体L配位,采取扭曲的八面体配位构型。乙腈溶液中,配合物1、2、4和5在410 nm处的最大荧光发射峰与配体L相似。而配合物3由于配体到锌离子之间的能量转移,最大荧光发射峰红移至430 nm。  相似文献   

6.
在甲醇体系中,分别将苯并咪唑席夫碱HL~1和HL~2与高氯酸镍进行配位反应得到2个结构类似的镍配合物[Ni(L~1)_2]·2H_2O(1)和[Ni(L~2)_2]·2H_2O(2)(HL~1=N-(benzimidazol-2-ylethyl)-5-chlorosalicylideneimine,HL~2=N-(Benzimidazol-2-ylethyl)-5-bromosalicylidenei-mine),并用元素分析、红外光谱、紫外-可见光谱和单晶X射线衍射对其结构进行了表征。结构分析表明:两个配合物均属于单斜晶系,C2/c空间群,Ni(Ⅱ)与来自2个席夫碱配体的4个氮原子和2个氧原子配位,形成八面体结构。配合物中的氢键将配合物1和配合物2分别连接成二维和三维网络结构。选取金黄色葡萄球菌和大肠杆菌作为菌种,研究了2个席夫碱配体和2个配合物的抑菌能力。  相似文献   

7.
通过使用四臂八齿Schiff配体(H4L)与六水合硝酸钴反应,成功合成了Co(Ⅱ)席夫碱配合物C26H26N3O3Co.3H2O,并使用元素分析、IR光谱及单晶X射线衍射等方法对配合物进行了表征.结构分析表明,配合物中的配体通过3个分枝上的N和O原子与金属离子配位,形成扭曲的八面体几何构型,配体上未参与配位的分枝发生了水解,氨基发生了质子化,且配合物通过分子间氢键的弱相互作用沿晶体学a轴方向排列成1D链状结构.  相似文献   

8.
张曙光  冯云龙 《中国化学》2009,27(5):877-881
四唑酸(–CN4H)与羧酸(–COOH)具有相似的酸性。对苯酚四唑硫酮(H2L)可以作为单齿(–S或–N)或双齿(–N, N或–N, S)配体与金属离子配位形成配位化合物。合成了4个以H2L为配体的金属(II)配合物:Co(HL)2(Py)2(H2O)2 (1), [Mn(HL)2(H2O)4]·2H2O (2), Mn(HL)2(Phen)2 (3), and [Zn(HL)2(Phen)2]·0.5H2O·1.5CH3OH (4),并用X−射线单晶衍射法测定了晶体结构。晶体结构分析表明,在这些配合物中所有的中心金属原子均呈现六配位的八面体构型。在配合物1和2中,HL–配体以氧原子与中心金属原子配位,而在配合物3和4中HL–配体则以硫原子与中心金属原子配位。  相似文献   

9.
利用2-乙酰基吡啶(acpy)和2-邻甲基苯胺在甲醇中回流反应得到新型希夫碱配体2-{1-[(2-甲基苯基)亚氨基]-乙基}吡啶)(mpep),通过溶剂热法将acpy和mpep与氯化镉反应得到2种新型氯桥连一维之字链结构Cd(Ⅱ)配位聚合物{[Cd(mpep)]Cl2}n(配合物1)和{[Cd(acpy)]Cl2}n(配合物2).利用单晶X射线衍射、核磁共振氢谱、元素分析和红外光谱对配合物1和配合物2进行结构表征.结果表明,配合物1和配合物2均为一维之字链状结构.在配合物1中,Cd与mpep配体中2个氮原子和4个氯原子配位,呈六配位顺式八面体构型,并通过2个Cl原子桥连形成一维之字链状结构.在配合物2中,中心金属Cd(Ⅱ)与acpy中的氮原子、氧原子和4个氯原子配位,也呈六配位顺式八面体构型,进一步通过Cl原子桥连相邻金属形成一维之字链状结构.在3种不同极性的溶剂(CH3OH,CH3CN和CH2Cl2)中,两种配位聚合物均呈现蓝色荧光(390~433 nm),说明2种配位聚合物具有弱溶剂效应;在固态室温下两种配位聚合物也呈现蓝色荧光,最大发射波长分别为440和473 nm.固态最大发射波长比溶液中红移的原因是分子中存在氢键,降低了基态与激发态之间的能级差.在室温下,配合物1和配合物2在3种溶液和固态中均显示出较长的荧光寿命(19.08~60.20μs).  相似文献   

10.
孙海英 《化学研究》2000,11(2):28-30
合成和表征了新的含硫席夫碱—安息香缩肼基二硫代甲酸甲酯 (H2 L)及与Mn(Ⅱ ) ,Co(Ⅱ ) ,Ni(Ⅱ )Zn(Ⅱ )和Cd(Ⅱ )生成的配合物 [M(HL) 2 ]。结果表明这些配合物中安息香缩肼基二硫代甲酸甲酯存在为去质子化的烯硫醇式三齿配体 ,通过甲亚胺基氮原子、醇羟基氧原子和烯硫醇硫原子配位 ,金属离子处于六配位的八面体环境。  相似文献   

11.
The synthesis, structure and spectral properties of a new cinnamoyl derivative of 2-acetyl-1,3-indandione (2AID), p-fluoro-cinnamoyl-1,3-indandione, LH and its metal(II) complexes with Cu(II), Zn(II) and Cd(II), are described. In order to verify the molecular structure of the free ligand and its metal complexes, model geometries based on the spectroscopic data were optimized using quantum chemical methods. The experimental spectroscopic data (IR and NMR) of the ligand, LH, complemented by the calculated ones, show that it exists in the exocyclic enolic form in the gas phase, solution and solid state. Good quality single crystals of Cd(II) complex were obtained from a DMSO solution and were studied by means of single-crystal X-ray diffraction. The data show bidentate coordination of the ligand and two DMSO molecules coordinated to the metal centre, thus forming a complex with octahedral geometry. On the contrary, the spectroscopic data on the amorphous samples indicate a square planar geometry of the Cu(II) complex and distorted octahedral geometry for Zn(II) and Cd(II) complexes with two water molecules coordinated to the metal centre. The used quantum chemical method for structure optimization of the transition metal complexes, B3LYP/LANL2DZ, shows very good agreement with the crystallographic data and, therefore, was also employed for structural determination for the non-crystalline complexes. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   

12.
4‐Triphenylmethyl‐1,2‐benzoquinone (TPMBQ) reacted with some metal ions and the structure of the new compounds had been identified. The metal to ligand ratio was 1:2 which was revealed by elemental analysis. The complexes were found to have octahedral geometry and their thermal stability was studied using thermogravimetric analysis technique. The molar conductance measurements revealed the electrolytic nature of the synthesized chelates. The IR spectra concluded the bidentate nature of the TPMBQ ligand while the 1H NMR revealed the presence of water molecules. The XRD spectra of Mn (II) and Fe (III) complexes concluded their crystalline structure while Co (II) and Cu (II) chelates refer to amorphous structures. The geometries of the TPMBQ ligand were optimized using Gaussian 09 W; density functional theory B3LYP method. (DFT)/basis set 6–311++G (d, p). HOMO and LUMO energy values for chelates, chemical hardness and electro‐negativity had been calculated. The ligand and its metal complexes had been examined against different kinds of bacteria such as Proteus vulgaris, Escherichia coli, Staphylococcus aurous and Bacillus subtitles to examine their antimicrobial activity. Molecular docking using Auto Dock tools were utilized.  相似文献   

13.
New Mn(II), Ni(II), Co(II) and Cu(II) complexes of an azo dye ligand based on p ‐phenylenediamine with 5‐nitro‐8‐hydroxyquinoline were synthesized and characterized using elemental analysis, inductive coupled plasma analysis, molar conductance, powder X‐ray diffraction, thermogravimetric analysis, magnetic moment measurements, and infrared, 1H NMR, electron ionization mass and UV–visible spectral studies. The spectral and analytical data reveal that the azo dye ligand acts as a monobasic bidentate ligand via deprotonated OH and nitrogen atom of the quinoline ring. The data support the formulation of all complexes with a 2:1 ligand‐to‐metal ratio, except the Mn(II) complex that has a mononuclear formula. All complexes have an octahedral structure. The molar conductance data reveal that all the metal complexes are non‐electrolytic in nature. From the X‐ray data, the average particle size of the ligand and its complexes is 0.32–0.64 nm. The colour fastness to light, washing, perspiration, sublimation and rubbing of the prepared ligand and its complexes on polyester fabrics and colorimetric properties were measured. The results reveal that the ligand and its complexes have a good to moderate affinity to polyester fibres.  相似文献   

14.
A series of Co(II), Cu(II), Y(III), Zr(IV), La(III), and U(VI) complexes derived from 2-(2-hydroxybenzylidinemine)-benzoic acid (L) ligand were synthesized. The mode of bonding of L and the structure of its metal complexes were investigated using different analytical and spectral tools (FT-IR, UV–Vis, 1H NMR, mass, and XRD). The ligand chelated with the metal ions as a neutral bidentate through oxygen and azomethine nitrogen atoms. All metal complexes adopted octahedral geometry with characteristic color for metal ions. The results of magnetic moment measurements supported paramagnetic for some complexes (Co(II) and Cu(II)) and diamagnetic phenomena for the other complexes. The thermal decomposition of the ligand along with its metal complexes was explained. The molar conductance values of all complexes in (DMF) were found in the range 154.50 to 250.20 S cm2 mol−1 at room temperature. The activation thermodynamic parameters, such as E*, ΔH*, ΔS* and ΔG*, were calculated from the DTG curves using Coats–Redfern (CR) and Horowitz–Metzeger (HM) methods at n = 1 or n ≠ 1. The nematicidal activity of the synthesized L and their metal complexes was screened.  相似文献   

15.
New bis-chelated ZnII and CdII complexes of empirical formula, [M(mpsme)2] (mpsme=the anionic form of the tridentate ONS donor ligand formed from methylpyruvate and S-methyldithiocarbazate) have been prepared and characterized by conductance, i.r., electronic and n.m.r. spectroscopic techniques. Spectral evidence supports a six-coordinate distorted octahedral structure for these complexes. X-ray crystallographic structural analysis also confirms that, in both the [Zn(mpsme)2] and [Cd(mpsme)2] complexes, the methylpyruvate Schiff base of S-methyldithiocarbazate is coordinated to the metal ions as a uninegatively charged tridentate ONS chelating agent via the carbonyl oxygen atom, the azomethine nitrogen atom and the thiolate sulfur atom. Both complexes are assigned a distorted octahedral geometry in which the ligands are arranged meridionally around the metal ions. The distortion from regular octahedral geometry is attributable to the restricted bite angles of the ligand.  相似文献   

16.
A series of chromone Schiff base complexes were prepared and analytically as well as spectroscopically characterized. The ligand was found to act as a monobasic tridentate ligand bonded covalently or coordinatively to the metal ion via deprotonated hydroxyl group, azomethine nitrogen atom and carbonyl oxygen atom of antipyrine moiety. Both electronic spectra and magnetic measurements indicated an octahedral or a distorted octahedral geometry around the metal ions for all metal complexes except the nickel complex, which had a tetrahedral geometry. In addition, the ability of the newly prepared compounds to activate the tumour suppressor p53 in cancer cells was studied, with zinc and copper complexes showing promising activities for p53 ubiquitination compared with diphenylimidazole (reference drug).  相似文献   

17.
Manganese(II), iron(II), cobalt(II), nickel(II), copper(II), and chromium(III) complexes of (E)-2-(2-(2-hydroxybenzylidene)hydrazinyl)-2-oxo-N-phenylacetamide were synthesized and characterized by elemental and thermal (TG and DTA) analyses, IR, UV-vis and (1)H NMR spectra as well as magnetic moment. Mononuclear complexes are obtained with 1:1 molar ratio except [Mn(HOS)(2)(H(2)O)(2)] and [Co(OS)(2)](H(2)O)(2) complexes which are obtained with 1:2 molar ratios. The IR spectra of ligand and metal complexes reveal various modes of chelation. The ligand behaves as a monobasic bidentate one and coordination occurs via the enolic oxygen atom and azomethine nitrogen atom. The ligand behaves also as a monobasic tridentate one and coordination occurs through the carbonyl oxygen atom, azomethine nitrogen atom and the hydroxyl oxygen. Moreover, the ligand behaves as a dibasic tridentate and coordination occurs via the enolic oxygen, azomethine nitrogen and the hydroxyl oxygen atoms. The electronic spectra and magnetic moment measurements reveal that all complexes possess octahedral geometry except the copper complexes possesses a square planar geometry. From the modeling studies, the bond length, bond angle, HOMO, LUMO and dipole moment had been calculated to confirm the geometry of the ligands and their investigated complexes. The thermal studies showed the type of water molecules involved in metal complexes as well as the thermal decomposition of some metal complexes. The protonation constant of the ligand and the stability constant of metal complexes were determined pH-metrically in 50% (v/v) dioxane-water mixture at 298 K and found to be consistent with Irving-Williams order. Moreover, the minimal inhibitory concentration (MIC) of these compounds against Staphylococcus aureus, Escherechia coli and Candida albicans were determined.  相似文献   

18.
A new Schiff base derived from the condensation of 2‐acetylferrocene with l ‐histidine was prepared and characterized using elemental analyses and spectroscopic methods. Cr(III), Mn(II), Fe(III), Co(II), Ni(II), Cu(II), Zn(II) and Cd(II) complexes of the Schiff base were prepared and characterized using various physicochemical methods such as elemental analysis, Fourier transform infrared and UV–visible spectroscopies, molar conductance, thermal analysis and scanning electron microscopy (SEM). Both ligand and complexes were investigated for their biological and anticancer activities. The elemental analyses showed that complexes were formed in a metal‐to‐ligand ratio of 1:1 stoichiometry. The spectral analyses proved that the ligand was tridentate and all complexes had an octahedral geometry, except the Zn(II) complex that was tetrahedral. SEM showed that the ligand and its Cd(II) complex were of nanometric structure. The molecular and electronic structure of the free ligand was optimized theoretically and the quantum chemical parameters were calculated. The molecular structure can be used to investigate the coordination sites and the total charge density around each atom. According to anticancer studies, Cd(II) complex was recommended to be used as anti‐breast cancer drug as it had very low IC50 (3.5 μg ml?1). Molecular docking was used to predict the binding between the free ligand and its Cd(II) complex and crystal structure of Staphylococcus aureus (PDB ID: 3Q8u), receptors of breast cancer mutant oxidoreductase (PDB ID: 3Hb5) and crystal structure of Escherichia coli (PDB ID: 3 T88) and to identify the binding mode and the crucial functional groups interacting with the three proteins.  相似文献   

19.
A new Schiff base, {1-[(2-hydroxy-naphthalen-1-ylmethylene)-amino]-4-phenyl-2-thioxo-1, 2-dihydro-pyrimidin-5-yl}-phenyl-methanone, has been synthesized from N-amino pyrimidine-2-thione and 2-hydroxynaphthaldehyde. Metal complexes of the Schiff base were prepared from acetate/chloride salts of Cu(II), Co(II), Ni(II), Zn(II), and Cd(II) in methanol. The chemical structures of the Schiff-base ligand and its metal complexes were confirmed by elemental analyses, IR, 13C-NMR, 1H-NMR, API-ES, UV-Visible spectroscopy, magnetic susceptibility, and thermogravimetric analyses. The electronic spectral data and magnetic moment measurements suggest mononuclear octahedral and mononuclear or binuclear square planar structures for the metal complexes. In light of these results, it was suggested that this ligand coordinates to each metal atom by hydroxyl oxygen, azomethine nitrogen, and thione sulfur to form octahedral complexes with Cd(II) and Zn(II).  相似文献   

20.
A new hydrazone ligand, HL, was prepared by the reaction of 7-chloro-4-hydrazinoquinoline with o-hydroxybenzaldehyde. The ligand behaves as monoprotic bidentate. This was accounted for as the ligand contains a phenolic group and its hydrogen atom is reluctant to be replaced by a metal ion. The ligand reacted with Cu(II), Ni(II), Co(II), Fe(III), and UO2(II) ions to yield mononuclear complexes. In the case of Fe(III) ion two complexes, mono- and binuclear complexes, were obtained in the absence and presence of LiOH, respectively. Also, mixed ligand complexes were obtained from the reaction of the metal cations Cu(II), Ni(II) and Fe(III) with the ligand (HL) and 8-hydroxyquinoline (8-OHqu) in the presence of LiOH, in the molar ratio 1:1:1:1. It is clear that 8-OHqu behaves as monoprotic bidentate ligand in such mixed ligand complexes. The ligand, HL, and its metal complexes were characterized by elemental analyses, IR, UV-vis, mass, and 1H NMR spectra, as well as magnetic moment, conductance measurements, and thermal analyses. All complexes have octahedral configurations except Cu(II) complex which has an extra square-planar geometry, while Ni(II) mixed complex has also formed a tetrahedral configuration and UO2(II) complex which formed a favorable pentagonal biprymidial geometry. Magnetic moment of the binuclear Fe(III) complex is quite low compared to calculated value for two iron ions complex and thus shows antiferromagnetic interactions between the two adjacent ferric ions. The HL and metal complexes were tested against one stain Gram positive bacteria (Staphylococcus aureus), Gram negative bacteria (Escherichia coli), and fungi (Candida albicans). The tested compounds exhibited higher antibacterial acivities.  相似文献   

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