GABAA五种亚型受体与BZ配基的3D-QSAR研究

GABAA受体是中枢神经系统内重要的抑制性受体,有广泛的神经生理活性.由于镇静/抗惊厥药物在临床上的广泛应用,使得其中苯并二氮杂作用位点尤为重要.我们用比较分子场法(CoMFA)对一系列咪唑苯并二氮杂类化合物（BZ）与五种重组受体亚型的亲和力进行了结构活性关系研究,得到的一组模型都有较高的交叉验证系数.并在此基础上,建立了非交叉验证的一组PLS模型.用该组模型对随机选择的6个化合物组成的测试集进行了预测,都得到了相当满意的结果,表明所建立的一组模型具有良好的预测能力.本研究对于设计高亲和力的BZ受体的配基和研究GABAA受体的模型有指导意义.     

Self-assembly of flexible supramolecular metallacyclic ensembles: structures and adsorption properties of their nanoporous crystalline frameworks

The syntheses, structures, and N2 adsorption properties of six new supramolecular metallacycles are reported. Flexible ditopic linkers, 1-4, with systematically varied lengths and conformational degrees of freedom were synthesized utilizing ester linkages. They were used in combination with (dppp)M(OTf)2, where M = Pt(II) and Pd(II), and cis-(Me3P)2Pt(OTf)2 to form flexible supramolecular metallacycles 5-10 in 88-98% isolated yields. Their structures were characterized via multinuclear NMR and X-ray crystallography. The metallacycles stack to form porous structures in the crystalline state. The pore dimensions depend on both the phosphorus ligands attached to the metals and the flexible linkers. Adsorption studies on the porous materials show that 5a, 6, 8, and 9 held 11.7, 16.5, 5.7, and 6.8 cm3/g STP of N2 at 77 K, respectively. A guest-exchange study with nitromethane and toluene reveals that the nanopore in 5 is flexible, a property which was transferred from the linker to the supramolecular structure in the solid state.     

精油化学的进展

本文粗略回顾了精油化学的新进展,对精油的研究方法、精油成分的合成及生源也有所论述。同时介绍了当前精油研究中常用的文献。     

Synthesis and Crystal Structure of Mixed-Ligand Ni(II) Complex of N-(1-Phenyl-3-methyl-4-benzylidene-5-pyrazolone) p-Nitrobezoylhydrazide and Pyridine

A novel mixed-ligand nickel complex, [Ni(PMBP—PNH) (Py)₃], [PMBP—PNH=N-(1-phenyl-3-methyl-4-benzylidene-5-pyrazolone) p-nitrobezoylhydrazide; Py = pyridine], has been synthesized by the hydrothermal method and characterized by elemental analysis, IR spectrum, thermal analysis, and single-crystal X-ray diffraction. The X-ray diffraction reveals that the nickel (II) ion in the title complex is in a slightly distorted octahedral arrangement of the ONO donor atoms of primary ligand PMBP-PNH and three N-donor atoms in the secondary ligand pyridine.     

Micro construction of poly(epsilon-caprolactone)/poly(L-lactic acid) blend film by solution casting under microwave irradiation

The micro construction of poly(epsilon-caprolactone) (PCL) and poly(L-lactic acid) (PLLA) blend films fabricated by solution casting under microwave irradiation was investigated by selective enzymatic degradation and scanning electron microscopy (SEM). The results were totally different from the blends obtained by conventional methods. The blend was more homogeneous and the PCL continuous phase more compact as no spherulites and tiny zone separation were observed from the film surface and no PCL network was observed inside the film, and the degradation of a PCL plank by Pseudomonas lipase was significantly retarded. The distributed PLLA micro spheres were enlarged and amorphous. The thermal behavior of the blend by microwave heating revealed that PCL and PLLA underwent a melting process, which induced the variations of the PCL phase and PLLA spheres. The weight loss caused by degradation of the PCL/PLLA blend obtained by conventional methods (B50c) is greater than that of the blend obtained by microwave methods (B50m), which reflects the change in morphology from a loose PCL network (B50c) to a dense PCL plank (B50m).     

Intramolecular electronic interactions in conjugated ferrocene-pi-extended-tetrathiafulvalene donor-pi-donor molecular hybrids

The synthesis of new hybrid ferrocene and pi-extended tetrathiafulvalene (TTF) donor(1)-pi-donor(2) molecular assemblies 16a-c has been carried out by a Wittig-Horner reaction of the respective phosphonate esters 15a-c with 2-(2-ferrocenylvinyl)-9, 10-anthraquinone (18) prepared by olefination of ferrocenecarboxaldehyde (14) and the anthraquinone phosphonium salt 17. Electrochemical studies show that the D(1)-pi-D(2) (D = donor) molecular assemblies 16a-c essentially retain the redox characteristics of both ferrocene and the pi-extended TTF components and the effects of solvent, temperature, scan rate, and working electrode are significant. Most importantly, pronounced intramolecular electronic interactions between the two donor moieties were observed by cyclic voltammetry and Osteryoung square wave voltammetry in both the ground and charged states. Semiempirical calculations support the electrochemical observations.     

安眠镇静药物的串联质谱分析方法

气相色谱以及气相色谱／质谱联用经常被用来分析生物体液样品中的药物。用这些方法分析时，需要在色谱分析前，进行长时间的样品制备和衍生化过程。本文描述了用地识别１６安眠镇静药物的ＥＩ／ＭＳ／ＭＳ过程，并且对两例服毒自杀者的尿样进行了检测。     

Enhancement of sensors selectivity by gas-diffusion separation : Part 1. Flow-injection potentiometric determination of cyanide with a metallic silver-wire electrode

The potentiometric response of a metallic silver-wire electrode in the presence of silver ion complexing agents is theoretically derived on the basis of the Nernst equation. The cyanide response is shown to be in good agreement with the theory. The analytical utility of this inherently non-selective sensor is demonstrated by its application in gas-diffusion flow-injection analysis. By making use of a membrane barrier that prevents other than gaseous species from passing through, the almost specific determination of cyanide becomes feasible. Gaseous interferents (i.e., hydrogen sulphide, sulphur dioxide and nitrogen oxides) are chemically converted prior to entering the gas-diffusion unit. The apparent selectivity coefficients thus obtained are significantly better than those reported for common cyanide-selective electrodes.     

萃取分光光度法测定水和硫酸中的硒

本文提出一种测定硒的分光光度法。在酸性介质中，四价硒氧化Ｉ成为Ｉ３，Ｉ３－和结晶紫形成的离子缔合物用二甲苯萃取，进行分光光度测定。硒的检出限是０．０５μｇ／ｍＬ。用磷酸和ＥＤＴＡ消除Ｆｅ＾３＋，Ｐｂ＾２＋，Ｈｇ＾２＋等离子的干扰影响。本法可不和硫酸中四价硒。     

Synthesis of a tetra-deuterium-labeled derivative of potent and selective anticancer agent AA005

Annonaceous acetogenins are a series of potent naturally occurring anticancer agents, which act as inhibitors of complex I in mitochondria. AA005, a mimicry of acetogenins, has been found as active as those natural products and to present high selectivities between cancer and normal cells. In order to investigate the further cell-based mechanism induced by AA005, a d⁴-labeled derivative of AA005 (AA005-d⁴) was designed to detect the drug permeation ability into the membranes. In this letter, the synthesis is reported of this deuterium-labeled compound, wherein a ethylene-d⁴ glycol unit is incorporated efficiently into the molecule skeleton by simple etherifications.