“眼镜”状碘化亚铜配合物的调光和双光子发光性质

将半柔性的π-不饱和双吡啶端基配体3-pebtd与CuI分别在不同的溶剂中分层扩散, 经自组装得到8种具有Cu₂I₂L₂构型的眼镜状碘化亚铜配合物. 利用X射线单晶衍射、 X射线粉末衍射和元素分析等方法确定了配合物的结构. 对配合物的光物理性质进行了表征, 结果表明, 不同溶剂中自组装得到的配合物的单光子发光均表现出单一荧光峰, 这可归因于卤素到配体的电荷转移( ³XLCT); 并且这些配合物的发光颜色由492 到518 nm可调, 量子产率为33.1%~68.5%. 同时, 这类配合物表现出较优异的双光子发光性质, 有望将其用于生物成像领域.     

Preparation and characterization of different polyelectrolyte complexes and their application as flocculants

 Polyelectrolyte complexes (PEC) from poly(diallyl-dimethyl-ammoniumchloride) PDADMAC and two different polyanions, formed in aqueous solution, were characterized by different methods (zeta-potential, net content, turbidity) and applied as flocculants. The flocculation of clay was investigated by sedimentation measurement as well as by a dynamic method, using a Fibre Optical Flocculation Sensor. The results of both methods showed that the most important advantages of PEC were the high velocity of sedimentation and a very broad range of the optimum flocculation concentration. In spite of the differences in the complex-forming behavior of the two polyanions used, no significant differences between complexes of the same composition but different polyanions are obtained. In contrast, the ratio of anionic to cationic charges is of great importance for the mechanism of flocculation. Received: 30 May 1997 Accepted: 22 September 1997     

Salting-out thin layer chromatography of transition metal complexes: A comparative study of the effect of increased number of CH2 groups in chelate rings

Summary The regularities previously established in salting-out thin-layer chromatography on silica gel of Co(III) complexes, in which the side chains of a specific chelate ring were successively increased in length, were also found to be valid for two series of Co(III) complexes of the EDTA type, in which different chelate rings were enlarged by one CH₂ group. It was found that in the case of complexes of the EDTA type the salting-out efficiencies were practically the same for all members of a series, while the values of the separation factors were paractically independent of the ammonium sulphate concentration in the solvent system used. The results obtained were consistent with the mechanism of nonspecific hydrophobic interactions. The method used can be applied to the separation of the members of the series of complexes that we investigated.     

Polymer-supported haloarene chromium dicarbonyl isonitrile complexes: a study of their synthesis and reactivity

Different arene Cr(CO)(3) complexes were supported on a polystyrene isonitrile resin by photochemical-promoted replacement of a chromium carbonyl ligand by the NC group. The supported complexes proved to be stable and were successfully used for further transformations. In particular, the reactivity of dichlorobenzene complexes to different nucleophiles was investigated and found to be comparable with that of the parent Cr(CO)(3) complexes.     

稀土配合物的光致发光和电致发光研究

报道了稀土配合物在光致发光和电致发光的应用,从结构和性能的角度,分析了沁同稀土配合物的发光特性以及不同第一配体和第二配体对光致发光和电致发光的影响。     

Spectrofluorimetric determination of stoichiometry and association constants of the complexes of harmane and harmine with beta-cyclodextrin and chemically modified beta-cyclodextrins

The association characteristics of the inclusion complexes of the beta-carboline alkaloids harmane and harmine with beta-cyclodextrin (beta-CD) and chemically modified beta-cyclodextrins such as hydroxypropyl-beta-cyclodextrin (HPbeta-CD), 2,3-di-O-methyl-beta-cyclodextrin (DMbeta-CD) and 2,3,6-tri-O-methyl-beta-cyclodextrin (TMbeta-CD) are described. The association constants vary from 112 for harmine/DMbeta-CD to 418 for harmane/HPbeta-CD. The magnitude of the interactions between the host and the guest molecules depends on the chemical and geometrical characteristics of the guest molecules and therefore the association constants vary for the different cyclodextrin complexes. The steric hindrance is higher in the case of harmine due to the presence of methoxy group on the beta-carboline ring. The association obtained for the harmane complexes is stronger than the one observed for harmine complexes except in the case of harmine/TMbeta-CD. Important differences in the association constants were observed depending on the experimental variable used in the calculations (absolute value of fluorescence intensity or the ratio between the fluorescence intensities corresponding to the neutral and cationic forms). When fluorescence intensity values were considered, the association constants were higher than when the ratio of the emission intensity for the cationic and neutral species was used. These differences are a consequence of the co-existence of acid-base equilibria in the ground and in excited states together with the complexation equilibria. The existence of a proton transfer reaction in the excited states of harmane or harmine implies the need for the experimental dialysis procedure for separation of the complexes from free harmane or harmine. Such methodology allows quantitative results for stoichiometry determinations to be obtained, which show the existence of both 1:1 and 1:2 beta-carboline alkaloid:CD complexes with different solubility properties.     

异双Schiff碱及其稀土配合物的合成、机理与波谱

利用2,6-二氨基己酸(赖氨酸)具有两端不对称结构的－NH~2基,合成了一端与水杨醛,另一端与2,4-二羟基苯甲醛缩合形成空间结构不对称的异双Schiff碱及其与稀土元素配合物。以元素分析、热分析、摩尔电导、红外光谱、EPR以及^1HNMR,^1^3C-^1HCOSY谱、固体高分辨^1^3C谱等表征,研究了这类不对称Schiff碱的形成机理和配位方式。     

Synthesis, Spectral and Thermal Studies of o-vanillin Oxime Complexes of Zinc(II), Cadmium(II) and Mercury(II)

Zinc(II), cadmium(II) and mercury(II) complexes of o-vanillin oxime have been synthesized and characterized by different physicochemical techniques. All the complexes have been subjected to non-isothermal decomposition studies in nitrogen atmosphere using thermogravimetry. The kinetic parameters for the decomposition of these complexes were evaluated using different methods and comparatively better results were obtained by these different methods. It has also been found that the decomposition processes of all these complexes follow first order kinetics. This revised version was published online in July 2006 with corrections to the Cover Date.     

Fluorescence study of inclusion complexes between star-shaped cholic acid derivatives and polycyclic aromatic fluorescent probes and the size effects of host and guest molecules

Star-shaped host molecules containing two, three, and four cholic acid moieties have been used to form inclusion complexes with polycyclic aromatic hydrocarbon probes (guests) varying in size from four (pyrene) to five (benzo(e)pyrene) and seven aromatic rings (coronene) and investigated by steady-state fluorescence measurements and fluorescence lifetime techniques. The results indicated that these hydrophobic guest probes prefer to locate in the hydrophobic cavities formed by the host molecules in an aqueous solution. Further studies showed that the stoichiometric ratios of the complexes depended on the relative size of both the host and the guest. The complexes of 1:1 ratio (guest:host) were formed between pyrene and the host molecules of different sizes, while the complexes of 1:2 ratio (guest:host) were found for coronene in all cases. For benzo(e)pyrene with an intermediate size, the complexes with 1:1 and 1:2 ratios (guest:host) were formed depending on the relative sizes of the host molecules. The stability of the inclusion complexes was observed to change with the solvent polarity, indicative of an adaptation of the hydrophobicity of the host pockets to the polarity of the solvent. The formation of the complexes was driven by the solvophobic interactions.     

C1桥联的茂金属化合物(Cp)CR1R2(Flu)MCl2的合成及其催化烯烃聚合活性

合成了6种单碳桥联的含芴(Flu)茂(Cp)基B族茂金属催化剂,研究了它们催化烯烃聚合的能力.通过IR,¹HNMR,EI-MS和元素分析对化合物进行了表征.用所合成的茂金属化合物与MAO所组成的催化体系对乙烯、丙烯的聚合进行了研究.其中金属为Ti的催化剂没有聚合活性或活性极低.金属为Zr的催化剂有一定的催化活性,用不同的催化剂得到的聚合物性质有一定的差异.     

Determination of aluminum in environmental and biological samples by reversed-phase high-performance liquid chromatography via pre-column complexation with morin

Morin was used as a pre-column reagent for the determination of aluminum by RP-HPLC with fluorescence detection. This method has been successfully applied to direct determination of trace Al in environmental and biological samples. The response was linear from 6 x 10(-9) to 6 x 10(-5) M with a detection limit of 2 x 10(-9) M. In addition, the different Al complexes with morin were separated by the proposed HPLC procedure and their coordination ratios were depicted by molar-ratio method. The results showed that 1:1 and 2:1 Al-morin complexes formed.     

Synthesis and characterization of Mo(VI) complexes derived from ONO donor acylhydrazones

Four new dioxomolybdenum(VI) complexes were prepared using different acylhydrazones. Hydrazones used for complexation were derived from 2-hydroxy-4-methoxybenzaldehyde, 2-hydroxy-4-methoxyacetophenone, benzhydrazide and nicotinoyl hydrazide. The complexes were characterized by various spectroscopic techniques, thermal and elemental analyses. The (1)H NMR and IR spectral data indicate tridentate nature of the ligands through enolization. IR spectra provide information about the dimeric nature of the complexes. The thermal analyses of the complexes showed the presence of lattice water in some of the complexes.     

Energy-resolved collision-induced dissociation cross sections of 2:1 bis-oxazoline copper complexes. Nonbonded interactions and nonlinear effects

Absolute ligand binding energies are determined for the 2:1 complexes of bis-oxazoline ligands and Cu(I) in the gas phase by the fitting of energy-resolved collision-induced dissociation cross sections. The complexes were chosen for their occurrence in asymmetric catalysis for which the phenomenon of nonlinear effects is explained by differences in stability for homochiral and heterochiral complexes. Pseudo-enantiomeric ligands are used so that mass spectrometric measurements can be employed. The measurements find that the sterically similar, but electronically different, isopropyl versus phenyl substituents lead to a different stability ordering of the homo- versus heterochiral complexes, which then leads to the prediction of nonlinear effects in asymmetric catalysis by the complexes with isopropyl-substituted ligands. The origin of the difference in stability order is found in noncovalent interactions between the phenyl groups on the ligands, which are poorly described by DFT calculations.     

Synthesis and mesomorphism of ionic self-assembled complexes of anthraquinones

Anthraquinones are known to exhibit mesomorphism upon appropriate substitutions. In this report, the concept of ionic self-assembly has been applied to design and synthesise new anthraquinone-based liquid crystals. Four different anthraquinones were used as polyelectrolytes which form ionic complexes with double-tail ammonium surfactants. The chemical structures were characterised by spectral techniques and elemental analysis. The thermal behaviour of the complexes was investigated by polarising optical microscopy, differential scanning calorimetry, thermogravimetric analysis and X-ray diffraction studies. All these complexes display lamellar mesomorphism. The amphotropic nature of the complexes has also been studied.     

Mössbauer and positron annihilation studies of microstructural peculiarities of iron-dextran complexes

The microstructural peculiarities of pharmaceutically important iron-dextran complexes were studied by Mössbauer and positron annihilation techniques. The results of Mössbauer spectroscopy showed variations of the iron cores in iron-dextran complexes containing different forms of FeOOH and different electronic and magnetic states of iron. The results of angular correlations of annihilation radiation and positron life-time spectroscopies showed microstructural variations of the dextran shell of the iron-dextran complexes.     

New computational strategy to analyze the interactions of ERalpha and ERbeta with different ERE sequences

The importance of computational methods for the simulation and analysis of biological systems has increased during the last years. In particular, methods to predict binding energies are developing not only with the aim of ranking the affinities between two or more complexes, but also to quantify the contribution of different types of interaction. In this work, we present the application of HINT, a non Newtonian force field, to rank the affinities of complexes formed by estrogen receptors (ER) alpha and beta and different estrogen responsive elements (ERE) near the estrogen-regulated genes. We used the crystallographic coordinates of the DNA binding domain of ERalpha complexed to a consensus ERE as a starting point to simulate several complexes in which some nucleotides in the ERE sequence were mutated. Moreover, we used homology modeling methods to create the structure of the complexes between the DNA binding domain of ERbeta (for which no experimental structures are currently available) and the same ERE sequences. Our results show that HINT is able to rank the affinities of ERalpha and ERbeta for different ERE sequences, and to correctly identify the positions on the DNA sequence that are most important for binding affinity. Moreover, the HINT output gives us the opportunity to identify and quantify the role played by each single atom of amino acids and nucleotides in the binding event, as well as to predict the effect on the binding affinity for other nucleotide mutations.     

核苷磷酸盐对含双芘侧链荧光敏感器化合物的荧光猝灭与分子识别

合成了一种在水溶液中对核苷磷酸盐ATP,ADP,AMP阴离子具有识别能力的荧光化学敏感器分子---化合物1。通过检测化合物1在水溶液中芘激基缔合物荧光发射强度随核苷磷酸盐、腺嘌呤等的加入而引起的变化,求出不同核苷磷酸盐及腺嘌呤对芘激基缔合物荧光发射的猝灭常数,并进行了比较研究。利用荧光发射强度随不同核苷磷酸盐引入而发生的变化计算出化合物1对不同核苷磷酸盐进行配位的配位稳定常数。结果表明所合成的化合物1对ATP有着良好的识别力选择功能。此外,还利用分子力学的计算方法对化合物1及其与核苷磷酸盐形成配合物后的分子构象及几何尺寸作了计算,并结合实验结果进行了初步讨论。     

聚烷基紫精电解质复合物催化偶氮苯的还原研究

本文报道了几种聚烷基紫精复合物的制备, 并研究了作为电子转移催化剂在偶氮苯还原中的作用, 结果显示,聚烷基紫精-聚阴离子复合物具有诱导偶氮苯还原的能力.并且不同聚电解质复合物具有不同的电子转移中介能力.     

Mass spectrometric studies on small open-chain piperazine-containing ligands and their transition metal complexes

Electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry was used to characterize the complexes formed between open-chain piperazine-containing ligands and transition metal salts (Cobalt, Copper, Zinc, and Cadmium as chlorides, nitrates, and acetates). Only single-charged complexes were observed, formed of one ligand (L) and mainly one metal ion (M). Since the net charge of the complexes was one, a counterion (X) was attached to some of the complexes, with formation of [L + M + X]+ complexes, and a proton was lost from others, as in [L - H + M]+ complexes. In most cases the composition of the complexes was more dependent on the ligand than the metal salt. Collision-induced dissociation measurements showed that complexes with related composition often differed in structure, or that interactions between the ligand and the metal ion were not alike. The metal ion influenced considerably the fragmentation pathways of the ligands, so that the fragmentation products could be used to deduce the binding sites of the metal. The variations observed in fragmentation behavior of complexes possessing the same ligand but different metal ions can mostly be explained by the ionic radius and electronic configuration of the metal ion. The results indicated a preference of the piperazine ring of the coordinated ligand for the boat conformation.     

鱼精蛋白-siRNA不同形貌复合体的制备、 结构及药效学分析

利用涡旋混匀及室温孵育的方法制备了不同形貌的鱼精蛋白-siRNA复合体, 并利用聚丙烯酰胺凝胶电泳结合银染、 原子力显微镜和透射电子显微镜等手段进行了结构表征. 结果表明, 鱼精蛋白可以和不同的siRNA分子以不同的质量比形成球形和纤维状鱼精蛋白-siRNA复合物. 在此基础上, 利用Mg²⁺等金属离子探针, 确认鱼精蛋白与siRNA的磷酸-戊糖骨架之间通过静电力发生作用. 利用原子力和透射电子显微镜表征了鱼精蛋白-siRNA复合体的形貌和结构特征; 利用激光纳米粒度仪测量了该复合体的粒径; 并进一步比较了黑色素瘤细胞对不同形貌复合体的吞噬及药效学特征.