PMBP缩氨基酚配合物的合成、结构和抑菌活性

利用PMBP缩邻、间和对氨基酚配体(C23H19N3O2), 合成了它们的Cu (II), Co (II), Fe (II) 和Zn (II) 配合物. IR, UV, 1 H NMR和EI-MS测定结果表明PMBP缩邻氨基酚配体以负二价三齿形式与金属形成1:1的配合物, 而PMBP缩间氨基酚和PMBP缩对氨基酚配体均以二齿形式与金属形成2:1的配合物。抑菌活性测定结果表明配合物对金黄色葡萄球菌和大肠杆菌的抑制活性大于配体, 其中PMBP缩邻氨基酚合钴(II) 配合物在2.5 g/L浓度下对大肠杆菌的抑菌环直径达到19 mm, 为研究配合物的生物活性提供了科学依据。     

两个新型氮氧自由基及其配合物的合成、晶体结构和磁性

合成并表征了两种新的含有酰氨基取代的氮氧自由基配体L1和L2。将L1和L2与六氟乙酰丙酮盐(Co(II), Ni(II),Mn(II))配位得到五个新的单核金属配合物L1Co(hfac)2, L1Ni(hfac)2, L2Co(hfac)2,L2Ni(hfac)2和L2Mn(hfac)2。对L1和L2及其配合物的结构和磁性进行了表征，在配合物中氮氧自由基的氧和取代基羰基氧均和金属离子配位，自由基和金属离子之间存在着强的反铁磁相互作用。     

新型含2,5-二-（3,5-二甲基吡唑-4-巯基）-1,3,4-噻二唑-M(M=Co2+,Cd2+,Mn2+)配合物的合成、晶体结构及其抑菌活性研究

将配体L[2,5-二-(3,5-二甲基吡唑-4-巯基)-1,3,4-噻二唑]与Co(NO3)2 6H2O,Cd(NO3)2 4H2O和MnCl2 4H2O进行配位反应,得到三个配合物[Co(L)2(H2O)4](NO3)2 4(CH3CH2OH)(1),[Cd(L)2(H2O)4](NO3)2 4(CH3CH2OH)(2),[Mn(L)2(Cl)2(CH3OH)2]2(CH3OH)(3),并用元素分析,FT-IR和X射线单晶衍射进行了表征.分析结果表明,配体L呈"U"形,配合物1～3呈"S"形.配合物中Co(II),Cd(II),Mn(II)的配位环境均为扭曲八面体,每个金属离子同时和两个配体进行配位.配体和配合物体外抑菌活性研究结果表明,配体及其配合物都有一定的抑菌活性.     

大黄酸金属配合物的合成、表征及抗氧化活性研究

以天然大黄酸为原料合成了三种大黄酸金属配合物. 通过元素分析、摩尔电导、紫外光谱、红外光谱、热重差热、核磁共振氢谱和荧光分析测定配合物的组成和性质. 结果表明配合物组成为ML₂•2H₂O [M＝Cu(II), Fe(II), Mn(II)|L＝rhein(失去1-OH中质子)]. 并对配体和配合物进行了清除超氧自由基(O )、羟自由基(•OH)、DPPH•自由基的对比研究. 抗氧化试验结果表明, 金属配合物抗氧化活性均强于配体.     

新型水溶性手性Salen配合物的合成及性质研究

合成并表征了新型水溶性手性Salen 配体(R,R)-N,N’-二{4-[2-(三甲胺基)乙氧基]水杨醛}-1,2-环己二胺二高氯酸盐(L)及金属配合物ML [M＝Zn(II), Cu(II), Ni(II), Co(II), Fe(III), Mn(III)]. 讨论了手性配体L及配合物ZnL的电子光谱和圆二色光谱性质, 用UV-Vis光谱滴定和CD光谱滴定法研究了ZnL对手性氨基酸对映异构体的分子识别. 测定了主体ZnL与客体氨基酸轴向配位反应的配位数(n)、缔合常数(K)及热力学函数 测得缔合常数的大小顺序为KPhe＞KVal＞KThr. 研究发现反应是放热、熵减小的过程. 用凝胶电泳的方法初步研究了此类手性金属配合物在H2O2存在下对DNA的裂解作用.     

2,9-二甲基-1,10-菲咯啉的α-氨甲基吡啶衍生物的合成表征及其Mn(II),Co(II),Ni(II),Cu(II),Zn(II)配合物稳定性研究

以2,9-二甲基-1,10-菲咯啉为初始原料,合成了2,9-二甲基-1,10-菲咯啉的α-氨甲基吡啶衍生物-N,N'-二(2'-吡啶基)甲基-1,10-菲咯啉-2,9-二甲胺(L).该配体经过元素分析、红外光谱、核磁共振氢谱表征.在25±0.1℃、I=0.1mol·dm-3NaNO3的条件下,用pH电位滴定法测定了该配体在水溶液中的质子化常数及其分别与Mn(II),Co(II),Ni(II),Cu(II)和Zn(II)的配合物的稳定常数,提出了配合物的可能结构.进一步讨论了相应稳定常数较大的内在原因.     

N-支套索冠醚异羟肟酸的合成及其钴(II)配合物的氧加合性能

由乙二胺四乙酸二酐和多缩乙二醇出发,合成了一系列具有N-支套索冠醚结构的二异羟肟酸配体(L1H2~L4H2)及其钴(II)配合物(Co L1~Co L4),以IR,1H NMR,MS和元素分析进行结构表征。测定在不同温度下Co L1~Co L4的氧加合常数In KO2和热力学参数ΔH0、ΔS0,研究了氮杂冠醚环的大小对配合物氧加合性能的影响。     

含四硫富瓦烯Schiff碱配体和配合物二阶非线性光学性质的密度泛函理论研究

采用密度泛函理论(DFT)B3LYP(UB3LYP)/6-31g*方法对含四硫富瓦烯Schiff碱配体和它的Fe(III/II),Co(II),Ni(III/II),Cu(II)配合物的极化率和二阶非线性光学(NLO)性质进行了研究,并对其中闭壳层分子采用含时密度泛函理论(TD-DFT)方法计算了电子光谱.结果表明:含四硫富瓦烯Schiff碱配体本身具有较大的二阶NLO系数,二价金属配合物二阶NLO系数与配体接近,三价金属配合物二阶NLO系数约为配体的30倍.金属配合物不同自旋多重度时其二阶NLO系数相差不大.结合配体和配合物的前线分子轨道分析可知,配体和二价金属配合物的二阶NLO系数主要是配体内的电荷转移(ILCT)的贡献,三价金属配合物既有ILCT又有金属与配体间电荷转移(MLCT),同时前线分子轨道能级差显著减小,因此它们的二阶NLO系数显著增大.     

脲基苯乙炔4-′(对甲基苯基)-6-苯基-2,2′-二联吡啶铂(II)络合物的合成

本文通过异氰酸酰化反应合成了含有脲基的苯乙炔新型配体及以它作为辅助配体的4′-(对甲基苯基)-6-苯基-2,2′-二联吡啶铂(II)络合物,初步研究了铂(II)络合物的光物理性质,发现由于脲基的存在,当浓度大于3.32×10-5mol/L时铂(II)络合物能够发生分子间簇集.     

双大环配体与铜双核配合物的合成、晶体结构和磁偶合性质

由新型双功能配体2,6-双(1,5,9-三氮杂环十二烷)-2,6-二甲基苯甲酸(L)与溴化铜在甲醇中反应得到新型铜双核配合物[Cu~2LBr~2]Br.3H~2O单晶。晶体结构分析表明:2个Cu(II)中心离子由配体L中的羧酸基团桥联;2个等价的Cu(II)中心离子均由双功能配体L的1,5,9-三氮杂环十二烷([12aneN~3)的3个氮原子和羧酸的1个氧原子及1个Br^-离子配位,并都处在三角双锥的配位环境中;分子内Cu...Cu双核间的距离为0.5884(6)nm。变温磁化率数据表明:在同一分子中的2个铜核之间存在反铁磁偶合作用(J=-22.49cm^-^1)。     

The Stability Constants of Complexes of BDBPH- Metals and Species Distributions

The study on the design and synthesis of model compounds for metalloproteins has been a subject of extensive investigation1. During the last decade, a number of synthetic structural models for some kinds of metalloproteins with several types of ligands have been reported in literature2,3,4. We have recently reported a new 24-membered hexaazadiphenol macrocyclic ligand, 3,6,9,17,20,23-hexaaza-29,30-dihydroxy-13,27-dimethyl-tricyclo [23,3,1,111,15] triaconta-1 (28),11,13,15 (30),25,26-hexaene,…     

Oxidative degradation of beta-diketiminate ligand in copper(II) and zinc(II) complexes

Copper(II) and zinc(II) complexes supported by a popular beta-diketiminate ligand (1(-), 2-mesitylamino-4-mesitylimino-2-pentene), [CuII(1)(AcO)] and [[ZnII(1)]2(mu-MeO)(mu-AcO)], have been demonstrated to undergo an oxidative degradation to give a ketone diimine derivative (2) under aerobic conditions. The crystal structures of the mononuclear copper(II) and dinuclear zinc(II) complexes of the beta-diketiminate ligand as well as the copper(II) complex of the modified ligand have been determined by X-ray crystallographic analysis. Mechanism for the oxidative degradation reaction of the beta-diketiminate ligand is also discussed.     

Ca(II), Sr(II) and Ba(II) ion interaction with the rheumatoid arthritis drug tenoxicam: Structural,thermal, and biological characterization

Recently, one of the most common conditions that manifests as joint and muscle inflammation is rheumatoid arthritis. One of the treatments for this arthritis includes non‐steroidal anti‐inflammatory drugs (NSAIDs) of the oxicam family, and the widest used drug in this family is tenoxicam (Tenox). In this study, the complexation properties of the drug Tenox with Ca(II), Sr(II) and Ba(II) ions in a (dichloromethane + water) binary solvent system are reported. The formed metal complexes were characterized structurally, thermally, and biologically. Tenox was found to act as a chelate monoanionic ligand towards all metal ions with complexation stoichiometry of 1:2 (Metal: Tenox) for Ca(II) and Sr(II) ions, and 1:1 for Ba(II) ions. The Tenox ligand behaves as a bidentate ligand when coordinated with Sr(II) or Ba(II) ions and as a tridentate ligand when coordinated with Ca(II) ions. The Sr(II) and Ba(II) complex of the Tenox ligand exhibited marked inhibitory effect on the cell growth of the C. albicans species.     

Synthesis, characterization and biological activities of Cu(II), Co(II), Mn(II), Fe(II), and UO2(VI) complexes with a new Schiff Base hydrazone: O-hydroxyacetophenone-7-chloro-4-quinoline hydrazone

The Schiff base hydrazone ligand HL was prepared by the condensation reaction of 7-chloro-4-quinoline with o-hydroxyacetophenone. The ligand behaves either as monobasic bidentate or dibasic tridentate and contain ONN coordination sites. This was accounted for be the presence in the ligand of a phenolic azomethine and imine groups. It reacts with Cu(II), Ni(II), Co(II), Mn(II), UO(2) (VI) and Fe(II) to form either mono- or binuclear complexes. The ligand and its metal complexes were characterized by elemental analyses, IR, NMR, Mass, and UV-Visible spectra. The magnetic moments and electrical conductance of the complexes were also determined. The Co(II), Ni(II) and UO(2) (VI) complexes are mononuclear and coordinated to NO sites of two ligand molecules. The Cu(II) complex has a square-planar geometry distorted towards tetrahedral, the Ni(II) complex is octahedral while the UO(2) (VI) complex has its favoured heptacoordination. The Co(II), Mn(II) complexes and also other Ni(II) and Fe(III) complexes, which were obtained in the presence of Li(OH) as deprotonating agent, are binuclear and coordinated via the NNNO sites of two ligand molecules. All the binuclear complexes have octahedral geometries and their magnetic moments are quite low compared to the calculated value for two metal ions complexes and thus antiferromagnetic interactions between the two adjacent metal ions. The ligand HL and metal complexes were tested against a strain of Gram +ve bacteria (Staphylococcus aureus), Gram -ve bacteria (Escherichia coli), and fungi (Candida albicans). The tested compounds exhibited high antibacterial activities.     

Synthesis, spectral characterization, and thermal behavior of mononuclear Cu(II), Co(II), Ni(II), Mn(II), and Zn(II) complexes with 5-bromosalycilaldehyde isonicotinoylhydrazone

A bidentate/tridentate 5-bromosalycilaldehyde isonicotinoylhydrazone Schiff base was synthesized by condensing 5-bromosalycilaldehyde with isonicotinoylhydrazine. Cu(II), Co(II), Ni(II), Mn(II) and Zn(II) complexes of this chelating ligand were synthesized using nitrates of these metals. The ligand and the complexes were characterized by elemental analysis, UV–Vis, IR and EPR spectroscopy, conductance and magnetic susceptibility measurements, fluorescence, cyclic voltammetry and thermogravimetric analysis. The ligand and Zn(II) complex exhibits solid-state photoluminescence at room temperature.     

Synthesis,characterization, thermal decomposition studies and dyeing properties of some novel transition metal complexes of an azo derivative formed from 2-aminothiophene

An azo derivative was synthesized by coupling diazotized 2-amino-3-carbethoxy-4,5-dimethylthiophene with 2-naphthol and this new ligand formed a series of metal complexes with Mn(II), Co(II), Ni(II), Cu(II) and Zn(II) salts. These complexes were characterized on the basis of elemental analyses, molar conductance, magnetic susceptibility measurements, UV-Visible, IR and ¹H NMR spectral data. Analytical data revealed that all the complexes exhibited 1: 1 metal-ligand ratio. Spectral studies showed that the ligand existed in an internally hydrogen bonded azo-enol form rather than the keto-hydrazone form and coordinated to the metal ion in a tridentate fashion. On the basis of electronic spectral data and magnetic susceptibility measurements, suitable geometry was proposed for each complex. The ligand and its cobalt(II) complex were subjected to X-ray diffraction study. The thermal behaviour of the ligand and its copper(II) complex was examined by thermogravimetry. The ligand and its copper(II) and nickel(II) complexes were applied to silk fabric and their fastness properties were evaluated.     

Transition metal complexes of isonicotinic acid (2-hydroxybenzylidene)hydrazide

A new series of transition metal complexes of Schiff base isonicotinic acid (2-hydroxybenzylidene)hydrazide, HL, have been synthesized. The Schiff base reacted with Cu(II), Ni(II), Co(II), Mn(II), Fe(III) and UO2(II) ions as monobasic tridentate ligand to yield mononuclear complexes of 1:2 (metal:ligand) except that of Cu(II) which form complex of 1:1 (metal:ligand). The ligand 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 distorted towards tetrahedral. While, the UO2(II) complex has its favour hepta-coordination. The ligand and its metal complexes were tested against one strain Gram +ve bacteria (Staphylococcus aureus), Gram -ve bacteria (Escherichia coli), and Fungi (Candida albicans). The tested compounds exhibited higher antibacterial activities.     

Facile Template Synthesis in the System Ni(II)-Dithiooxamide-Acetaldehyde on Gelatin-immobilized Nickel(II) Hexacyanoferrate Matrices

Template synthesis of a nickel(II) chelate with an (N'N'S'S)-donor ligand, 4'6-dimethyl-2'8-di-thio-3'7-diaza-5-oxanonanedithioamide-1'9, with a metal ion:ligand ratio of 1:1 is realized in getalin-immobilized nickel(II) hexacyanoferrate(II) matrices contacting with aqueous solutions containing dithiox-amide, acetaldehyde (pH > 10), where the latter two compounds play the role of ligand synthons. On directcontact of dithioxamide and acetaldehyde in the solution in the absence of Ni(II), the above (N,N,S,S)-donorligand does not form, and no nickel(II) chelates with this ligand can be obtained by reactions of known nickel(II) dithiooxamide complexes with acetaldehyde.     

A study of a newly synthesized ligand and its metal complexes in bulk and nano size and metal uptake efficiency

A newly synthesized ligand derived from 2-amino thiophenol and benzoic anhydride and its Co(II), Cd(II), La(III) (in bulk and nano size), and Gd(III) complexes was investigated and characterized. The maximum elimination capacity of the newly synthesized ligand was investigated towards the removal of Co(II), Cd(II), La(III), and Gd(III) ions from aqueous solutions. It was found that the ligand has the best removal ability for Cd(II) metal of 98.66% at a concentration of 0.03 mg/L.     

Synthesis and characterization of transition metal complexes of N′-[(1,5-dimethyl-3-oxo-2-phenyl-2,3-dihydro-1H-pyrazol-4-yl)methylene]thiophene-2-carbohydrazide

A hydrazone ligand (HL) containing the thiophene moiety has been prepared via condensation of thiophene-2-carbohydrazide with 1,5-dimethyl-3-oxo-2-phenyl-2,3-dihydro-1H-pyrazole-4-carbaldehyde. The complexes of copper(II), nickel(II), cobalt(II), manganese(II), zinc(II), palladium(II), iron(III), ruthenium(III), uranyl(VI), and titanium(IV) with the ligand were prepared in good yield from the reaction of the ligand with the corresponding metal salts. The ligand and complexes were characterized using infrared, mass spectra, nuclear magnetic resonance, electronic absorption spectra, electron spin resonance, and magnetic moment measurements as well as elemental and thermal analyses. The results showed that the complexes are enolic by nature, whilst the ratio between the metal ion and the ligand depends on the acidity of the metallic ions and their oxidation numbers.