meso-四(4-N-取代吡啶基)卟啉铜(Ⅱ)配合物的合成及其对O-·2的清除作用

以Ｃｕ２（ＯＨ）２ＣＯ３为原料通过非均相金属插入反应合成ｍｅｓｏ－四（４－Ｎ－甲基吡啶基）卟啉合铜（Ⅱ）（ＣｕＴＭＰｙＰ）和ｍｅｓｏ－四（４－Ｎ－苄基吡啶基）卟啉合铜（Ⅱ）（ＣｕＴＢＰｙＰ）．方法操作方便，产率高．研究表明，在核黄素光照产生Ｏ－·２的体系中，ＣｕＴＭＰｙＰ和ＣｕＴＢＰｙＰ对Ｏ－·２具有明显的清除作用，对人红细胞内血红蛋白具有一定保护作用．     

改良铜钴催化剂体系上由合成气制混合醇的研究

在铜钴基催化剂体系上，由合成气制备混合醇的反应在６．０ＭＰａ的条件下进行．双活性组分体系中铜和钴是以强相互作用状态而共存的，分子探针实验表明，铜和钴的并存对于确保醇的碳链增长是重要的，助剂ＭｏＯ_ｘ的加入显著提高了Ｌａ_２Ｚｒ_２Ｏ_７担载的铜钴基催化剂Ｃｏ／ＣｕＬＺ的活性和选择性，其作用主要表现为通过氢的可逆溢流效应而改善了体系的氢化性能，和增大了ＣＯ的插入反应能力。在改良催化剂体系上，获得了５３％的醇选择性和１４７ｇ／Ｋｇｃａｔ／ｈ的混合醇产率，内含３３％的高级醇。     

CoMo／Al_2O_3和CoMo／TiO_2－Al_2O_3加氢脱硫催化剂的研

研究了ＣｏＭｏ／Ａｌ２Ｏ３和ＣｏＭｏ／ＴｉＯ２－Ａｌ２Ｏ３催化剂的加氢脱硫性能，并用ＬＲＳ，ＸＲＤ和ＴＰＳ等方法表征其表面相结构和硫化行为．结果表明，以ＴｉＯ２－Ａｌ２Ｏ３为担体的Ｍｏ和ＣｏＭｏ催化剂的活性均比相应的Ａｌ２Ｏ３为担体的高；少量Ｃｏ，Ｎｉ助剂的引入可显著提高ＭｏＯ３在担体上的分散度和改进催化剂的活性；Ｃｏ助剂还有降低Ｍｏ物种硫化温度的作用．     

血清中Mo、Se、Mn、Cu、Zn与食管癌的关系探讨

通过对１８例食管癌患者以及８０例对照组血清中Ｍｏ、Ｓｅ、Ｍｎ、Ｃｕ、Ｚｎ的测定分析，发现食管瘤患者血硒含量明显低于对照组，二者之间有极显著性差异（Ｐ＜０．０１）。而血铜、铜／锌比值食管癌组明显高于对照组，差异有显著性（Ｐ＜０．０５）。Ｍｏ、Ｍｎ、Ｚｎ元素的含量在二组之间无显著性差异（Ｐ＞０．０５）．提示血清硒铜与食管癌有关。     

Pt－Mo／Al_2O_3和Pt－Co－Mo／Al_2O_3催化剂中Pt、Co助

利用ＴＰＲ、Ｈ_２－ＴＰＤ技术，考察了氢气氛下的Ｐｔ－Ｍｏ／Ａｌ_２Ｏ_３和Ｐｔ－Ｃｏ－Ｍｏ／Ａｌ_２Ｏ_３催化体系中物种和电荷交换的现象和规律，揭示了Ｐｔ和Ｃｏ在表面Ｍｏ物种还原过程中助剂作用的本质．Ｐｔ－Ｍｏ／Ａｌ_２Ｏ_３的ＴＰＲ、Ｈ_２－ＴＰＤ结果证明，由于微量Ｐｔ参与了表面Ｍｏ物种还原时的物种和电子交换，有效地降低了其还原温度．Ｒｔ－Ｍｏ／Ａｌ_２Ｏ_３在氢还原过程中，氢和Ｍｏ容易形成载有活动氢的氢物种，并储存在催化剂表面，这种活动氢在Ａｒ中，甚至Ａｒ－Ｈ２混合气中可以释放出来。Ｐｔ－Ｃｏ－Ｍｏ／Ａｌ２Ｏ３的研究结果表明，Ｃｏ可以进一步促进Ｍｏ的还原．在样品预还原过程中，氢和Ｃｏ可以形成氢物种，其上的氢具有更强的可动性，很容易溢流到Ｍｏ物种的边上促进其还原．根据以上规律可以推测，加氢脱硫催化剂中Ｃｏ和贵金属的作用是使催化剂更容易形成低价的配位不饱和的钼中心，也就是ＨＤＳ活性中心．     

活性炭为载体加氢脱氮催化剂的研究

Ｍｏ／Ｃ、Ｎｉ／Ｃ和Ｎｉ－Ｍｏ／Ｃ催化剂吡啶加氢脱氮研究表明，Ｍｏ／Ｃ催化剂在Ｍｏ含量小于３．６５％时，随着Ｍｏ含量的增加，脱氮活性增加，其后趋于稳定。Ｎｉ／Ｃ催化剂也具有加氢脱氮活性，在Ｎｉ含量为５％左右达到最大值。Ｎｉ－Ｍｏ／Ｃ催化剂只有在Ｎｉ和Ｍｏ相互匹配时才具有较高的活性。ＸＰＳ的研究表明，硫化后Ｎｉ－Ｍｏ／Ｃ催化剂的Ｍｏ主要是以ＭｏＳ２的模型存在的；Ｎｉ是以ＮｉＳ和Ｎｉ３Ｓ２的混合生存在     

合成甲醇和甲酸甲酯的Cu-Cr催化剂(英文)

以甲酸钠作为羰化催化剂,未还原的铜－铬作为氢解催化剂,在３８３ Ｋ,初始压力为５．０ＭＰａ的条件下浆态相合成甲醇。铜－铬催化剂采用三种方法制备：Ａ,ＣｕＯ和Ｃｒ_２Ｏ_３的简单混合;Ｂ,共沉淀法：Ｃ,络合法。结果表明,采用Ａ制得的铜－铬催化剂没有活性,络合法比共沉淀法活性高。在以络合法制备的催化剂中加入第三金属组分可改变催化剂的选择性,加入Ｃｏ、Ａｇ、Ｌａ和ＺｒＯ_２后甲醇的选择性得以提高,而加入Ｍｎ、Ｂａ和Ｍｇ,则甲酸甲酯的选择性高于甲醇的选择性。     

固相配位化学反应研究LXVII．金属铜表面M－S（M＝Mo，W）簇合物膜的组成

采用ＦＴＩＲ、ＸＰＳ和ＡＥＳ研究了金属铜表面Ｍ－Ｓ（Ｍ＝Ｍｏ，Ｗ）簇合物膜。结果表明，Ｍｏ（Ｗ）与铜表面的Ｃｕ＿２Ｏ反应，形成了Ｍｏ（Ｗ）－Ｓ－Ｃｕ键；簇合物膜由Ｍｏ（Ｗ）、Ｓ、Ｃｕ、Ｏ元素组成，分别呈＋６、－２、＋１、－２价，膜为多分子层结构并保持ＭｏＳ＿４，或ＷＳ＿２单元，膜表面只有Ｃｕ、Ｏ而不存在Ｍｏ（Ｗ）、Ｓ．膜层厚度与反应时间有关，时间越长，膜越厚。膜为多组分的复杂体系，其颜色是各组分统计分布的结果。     

不同金属离子对CO／Al_2O_3中Co的分布和CoMoK／Al_2O_3催化

在γ－Ａｌ２Ｏ３中加入Ｚｎ２＋，Ｍｇ２＋，Ｃｕ２＋或Ｃｒ３＋后用漫反射光谱法研究了它们对随后加人的Ｃｏ分布的影响，同时还研究了这些离子对水煤气变换反应催化剂ＣｏＭｏＫ／Ａｌ２Ｏ３的催化活性的影响．发现Ｚｎ２＋，Ｍｇ２＋具有阻止Ｃｏ进入载体内层的作用，Ｃｕ２＋，Ｃｒ３＋的作用则相反．四面体配位倾向强的金属离子能阻止Ｃｏ进入载体内层，从而促进水煤气变换反应的催化活性，而八面体配位倾向强的金属离子的效果刚好相反．在６５０℃下，１００ｇＡｌ２Ｏ３含７ｇＭｇＯ时，Ｍｇ能最大限度地阻止Ｃｏ向Ａｌ２Ｏ３内层扩散，从而提高了ＣｏＭｏｋ／Ａｌ２Ｏ３的催化活性．     

[Cu(L-His)(Phen)]·2ClO4·H2O的合成、表征及晶体结构

铜是生物体中必需的微量元素．生物体中大部分铜与两种以上生物配体形成混配配合物,与生命过程中酶的催化、物质的储存和运送及铜离子的转运过程有关,因此研究铜的生物配体（如氨基酸等）混配配合物对探索钢在生物体中的功能性作用机制有着重要意义．目前关于氨基酸一铜（Ｉ）一邻菲咯琳混配配合物的合成及其性质研究日益为人们所关注［’－’］．本文合成了Ｌ一组氨酸、 １,１０一邻菲咯批铜（ Ｅ）配合物,并进行了表征和Ｘ射线晶体结构分析．该配合物尚未见文献报道．１实验部分１．１仪器及试剂Ｃｌｌ（ＣＩＯ。）。·６Ｈ。Ｏ按文献…     

Acetylacetonate bis(thiosemicarbazone) complexes of copper and nickel: towards new copper radiopharmaceuticals

A series of copper(II) and nickel(II) 1,3-bis(thiosemicarbazonato) complexes have been synthesised by the reaction of the metal acetates with pyrazoline proligands. In each case the complexes have an overall neutral charge with a dianionic ligand. The copper 1,3-bis(4-methyl-3-thiosemicarbazonato complex has been characterised by X-ray crystallography, which shows the copper is in an essentially square-planar symmetric N(2)S(2) environment. The nickel 1,3-bis(4-methyl-3-thiosemicarbazonato) and nickel 1,3-bis(4-phenyl-3-thiosemicarbazonato) complexes have been characterised by X-ray crystallography and show that in these cases the nickel is in a distorted square-planar environment, but the bonding mode of the ligands is unusual; the nickel binds to one of the aza-methinic nitrogen atoms and one hydrazinic nitrogen, creating one five-membered N-N-C-S-Ni chelate ring and one four-membered N-C-S-Ni chelate ring. Interestingly, the X-ray structure of the ethyl analogue [1,3-bis(4-ethyl-3-thiosemicarbazonato)nickel(II)] shows that in this case the nickel is symmetrically coordinated in the usual manner. The nickel complexes are diamagnetic and the different coordination modes are confirmed in solution by NMR spectroscopy. The complexes are susceptible to oxidation in air and a nickel complex, in which the central methylene carbon has been oxidised, has been characterised by X-ray crystallography and NMR spectroscopy. Electrochemical measurements show that the copper complexes undergo a reversible one-electron reduction at biologically accessible potentials.     

Study of liquid-crystalline copper(II) β-enaminoketonates by EPR

The structure of the chelate unit and magnetic properties of the homologous series of liquid-crystalline bis{1-[4-(4-alkoxybenzoyloxy)phenyl]-3-amyl-1-aminoprop-1-en-3-onate)copper(II) complexes was studied by EPR. The direction of the orientation of liquid crystal molecules in an external magnetic field in the mesophase state was determined. The complexes have a square-planar structure of the chelate unit determining their mesomorphic properties.     

PNPP catalytic hydrolysis by mono- and binuclear transition-metal complexes with polyether-bridged dihydroxamic acids

Polyether-bridged dihydroxamic acids and their mono- and binuclear copper(II), and cobalt(II) complexes have been synthesized and employed as models to mimic hydrolase in the catalytic hydrolysis of p-nitrophenyl picolinate (PNPP). The kinetics and the mechanism of PNPP hydrolysis have been investigated. The kinetic mathematical model of PNPP cleavage by the complexes has been proposed. The effects of the different central metal ion, mono- and binuclear metal, the pseudo-macrocyclic polyether constructed by the polyethoxy group in complexes, and reactive temperature on the rate of PNPP catalytic hydrolysis have been examined. The results show that the transition-metal dihydroxamates exhibit high catalytic activity in the PNPP hydrolysis; the rate of the PNPP hydrolysis increases with the increase in pH of the buffer solution; the catalytic activity of binuclear complexes is higher than that of mononuclear complexes; the catalytic activity of copper(II) complex is about four times that of the cobalt(II) complex; the pseudo-macrocyclic polyether can synergetically activate H₂O coordinated to the metal ion with the central metal ion together and promote the PNPP catalytic hydrolysis.     

Galactose oxidase models: solution chemistry, and phenoxyl radical generation mediated by the copper status

Galactose oxidase (GO) is an enzyme that catalyzes two-electron oxidations. Its active site contains a copper atom coordinated to a tyrosyl radical, the biogenesis of which requires copper and dioxygen. We have recently studied the properties of electrochemically generated mononuclear Cu(II)-phenoxyl radical systems as model compounds of GO. We present here the solution chemistry of these ligands under various copper and dioxygen statuses: N(3)O ligands first chelate Cu(II), leading, in the presence of base, to [Cu(II)(ligand)(CH(3)CN)](+) complexes (ortho-tert-butylated ligands) or [(Cu(II))(2)(ligand)(2)](2+) complexes (ortho-methoxylated ligands). Excess copper(II) then oxidizes the complex to the corresponding mononuclear Cu(II)-phenoxyl radical species. N(2)O(2) tripodal ligands, in the presence of copper(II), afford directly a copper(II)-phenoxyl radical species. Addition of more than two molar equivalents of copper(II) affords a Cu(II)-bis(phenoxyl) diradical species. The donor set of the ligand directs the reaction towards comproportionation for ligands possessing an N(3)O donor set, while disproportionation is observed for ligands possessing an N(2)O(2) donor set. These results are discussed in the light of recent results concerning the self-processing of GO. A path involving copper(II) disproportionation is proposed for oxidation of the cross-linked tyrosinate of GO, supporting the fact that both copper(I) and copper(II) activate the enzyme.     

OPTICAL ROTATION STUDIES OF COPPER (II)-TRIPEPTIDE COMPLEXES

Abstract

Copper(II) complexes of various optically active di- and tripeptides have been studied with the aid of optical rotatory dispersion (ORD) and circular dichroism (CD) techniques. The magnitudes of the molecular rotations related to the d-d transitions of the complexes fall into three different ranges, depending on the positions of asymmetric carbon atoms of the ligands. The molecular rotations of GAG and GLG complexes are greater than those of GGA, GGL, and GGV complexes, which are again greater than those of AGG, LGG, and VGG complexes (G, A, L, and V are glycine, alanine, leucine, and valine residues, respectively, in the tripeptides investigated, the N-terminal residue being the first residue in each abbreviation). The structures of these complexes, deduced from their potentiometric equilibrium curves and from the known crystal structure of the copper(II)-triglycine complex, show that the asymmetric carbon atoms of the second and third amino acid residues (counting from the N-terminal amino acid residue) are in the plane composed of the central metal ion, the nitrogen atoms of the amino and peptide groups, and the oxygen atom of the carboxylate group. The magnitude of the Cotton effect increases with the planarity of the chelate rings which include the asymmetric carbon atom and the metal ion, and with increasing strength of the coordinate bonds that form these chelate rings. Further support for this interpretation is found in the CD spectra of the copper(II) and nickel(II) complexes of AGG, GAG, GGA, and AAA. Analysis of the CD spectra of LL and DL alanylalanine complexes also demonstrate the influence of planarity and coordinate bond strength on the magnitude of the Cotton effect. Schiff base formation of aldehydes and ketones with dialanines causes fundamental changes in the geometries of the copper(II) complexes and reverses the relative contributions of the chelate rings to the total CD absorption intensities of the complexes.     

Oligonuclear copper complexes of a bioinspired pyrazolate-bridging ligand: synthesis, structures, and equilibria in solution

The synthesis of a new bioinspired dinucleating ligand scaffold based on a bridging pyrazolate with appended bis[2-(1-methylimidazolyl)methyl]aminomethyl chelate arms is reported. This ligand forms very stable copper complexes, and a series of different species is present in solution depending on the pH. Interconversions between these solution species are tracked and characterized spectroscopically, and X-ray crystallographic structures of three distinct complexes that correspond to the species present in solution from acidic to basic pH have been determined. Overall, this provides a comprehensive picture of the copper coordination chemistry of the new ligand system. Alterations in the protonation state are accompanied by changes in nuclearity and pyrazolate binding, which cause pronounced changes in color and magnetic properties. Antiferromagnetic coupling between the copper(II) ions is switched on or off depending on the pyrazole binding mode.     

Functionalized bis(thiosemicarbazonato) complexes of zinc and copper: synthetic platforms toward site-specific radiopharmaceuticals

Two new types of unsymmetrical bis(thiosemicarbazone) proligands and their neutral zinc(II) and copper(II) complexes have been synthesized. These bifunctional ligands both chelate the metal ions and provide pendent amino groups that can be readily functionalized with biologically active molecules. Functionalization has been demonstrated by the synthesis of three water-soluble glucose conjugates of the new zinc(II) bis(thiosemicarbazonato) complexes, and their copper(II) analogues have been prepared in aqueous solution via transmetalation. A range of techniques including NMR, electron paramagnetic resonance, cyclic voltammetry, high-performance liquid chromatography (HPLC), UV/vis, and fluorescence emission spectroscopy have been used to characterize the complexes. Four compounds, including two zinc(II) complexes, have been characterized by X-ray crystallography. The connectivity and conformation of the glucose conjugates have been assigned by NMR spectroscopy. Time-dependent density functional theory calculations have been used to assign the electronic transitions of the copper(II) bis(thiosemicarbazonato) chromophore. Two copper-64-radiolabeled complexes, including one glucose conjugate, have been prepared and characterized using radio-HPLC, and transmetalation is shown to be a viable method for radiolabeling compounds with copper radionuclides. Preliminary cell washout studies have been performed under normoxic conditions, and the uptake and intracellular distribution have been studied using confocal fluorescence microscopy.     

Studies on the reaction kinetics and the mechanism of hydrolysis of bis(4-nitrophenyl)phosphate (BNPP) by hydroxamic acid complexes containing benzo-15-crown-5

A hydroxamic acid (HL) containing benzo-15-crown-5 and their copper(II), zinc(II), cobalt(II) and manganese(II) complexes have been synthesized and studied as catalysts for the cleavage of bis(4-nitrophenyl)phosphate (BNPP). The catalytic properties of these complexes and the kinetics and mechanism of BNPP hydrolysis have been investigated. The kinetic mathematical model of BNPP cleavage catalyzed by these complexes has been proposed. The effects of reaction temperature and metal ion in the complexes on the rate of BNPP catalytic hydrolysis have been discussed. The results show that the hydroxamic acid complexes containing benzo-15-crown-5 exhibit high activity in the BNPP catalyzed hydrolysis; the pseudo-first-order-rate constants of BNPP hydrolysis catalyzed by the complexes increase along with the increases of pH of the buffer solution from 7.50 to 9.50; the activity of different metal ions decreases in the order: Co²⁺ > Cu²⁺ > Zn²⁺ > Mn²⁺; the pseudo-first-order-rate constants of BNPP hydrolysis catalyzed by the complexes is 2.24 × 10⁵ ~ 3.24 × 10⁵ times as large as that of spontaneous hydrolysis of BNPP.     

Synthesis and antioxidant, antimicrobial evaluation, DFT studies of novel metal complexes derivate from Schiff base

In Iraq, like most developing countries, attempts are being made to synthesize new compounds with several pharmacological properties. (E)-2-(3-(2-imino-1-methylimidazolidin-4-ylidene)-1-methylguanidino)acetic acid (L) has been synthesized and used as a ligand for the formation of Cr(III), Co(II), Ni(II), and Cu(II) complexes. The chemical structures of synthesized compounds were characterized using different spectroscopic methods. All chelates except Ni(II) chelate are found to be octahedral structures, Ni(II) chelate was square planar. The stability for the prepared complexes was studied theoretically using density function theory. The total energy for the complexes was calculated and it was shown that the copper complex is the most stable one. Ligand and complexes were tested against selected types of microbial organisms and showed significant activities. The free-radical scavenging activity of ligand and metal complexes have been determined by their interaction with the stable free-radical DPPH and all the compounds have shown encouraging antioxidant activities.     

TRANSITION METAL COMPLEXES OF AMINOPHOSPHONIC ACID ANALOGUES OF METHIONINE AND ALANINE IN AQUEOUS SOLUTION

Abstract

The stoichiometrics and stability constants of the nickel(II), copper(II) and zinc(II) complexes of l-amino-3-methylthiopropanephosphonic acid (MetP) and 1-amino-ethanephosphonic acid (a-AlaP) have been determined pH-metrically at 25°C at an ionic strength of 0.2 mol dm^?3 (KC1). From the stability data and the absorption spectra of the complexes it has been established that simple aminophosphonic acids coordinate to the nickel(II) and copper(II) ions forming chelate complexes in which the metal binding mode is bidentate with the {NH₂, PO₃ ^2-} donor set. ³¹P and ¹H NMR measurements showed that MetP and α-AlaP exhibit similar properties in the presence of zinc(II) ions, but the ligand reacts to form a cyclic phosphonoamidate in neutral and slightly alkaline solution in the Zn(II)-α-AlaP system and at slightly acidic conditions in the Zn(II)-MetP system. This difference reveals that the latter ligand at pH > 7 prefers Zn(II) coordination involving all possible (amino, phosphonate and thioether sulfur) donor groups.