新型非肽类血管紧张素II受体拮抗剂设计合成及其生物活性研究

Ang II受体拮抗剂是作用于肾素-血管紧张素系统(RAS)的抗高血压药，因其抗高血压作用与较老的抗高血压药物作用相同，且更具有选择性，不良反应状况与安慰剂相似,而在高血压治疗中逐渐引起研究者重视，并成为目前增长最快的抗高血压药物。在许多AngII受体拮抗剂中四氮唑结构已成为固定基团，但四氮唑有许多合成及代谢弊端。因此，寻找其他合适的杂环酸性基团来替代四氮唑，在保持较高口服活性的同时克服相应缺陷，具有极其重要的意义。 本项目以四氮唑沙坦类药物为先导化合物，运用生物电子等排原理及拼合原理，根据计算机分子模拟研究结果，对其进行结构修饰和改造，首次将咪唑、氯代咪唑、三氮唑及咪唑啉替代四氮唑，并结合具有较高AngII受体拮抗活性的联苯并咪唑衍生物，设计并合成一系列含咪唑，咪唑啉，氯代咪唑及三氮唑衍生物的Ang II受体拮抗剂。 研究这一系列新型AngII受体拮抗剂的体内、体外抗高血压活性时，发现咪唑啉衍生物展示了与对照药物几乎相当的活性，而咪唑、氯代咪唑和三氮唑衍生物分别表现了较弱或者没有活性，这些研究对今后更进一步设计合成新的Ang II受体拮抗剂具有重要的指导意义，同时也为筛选抗高血压药物奠定良好的基础。 The angiotensin II receptor antagonists act on renin-angiotensin system (RAS), which are as effective as other types of anti-hypertensive drugs. Because even the more specific and comparable to placebo in terms of side effects, Ang II receptor antagonists cause a high attention and become the fastest growing anti-hypertension drugs. Most of such compounds share the biphenyltetrazole unit with the lead Losartan. However, there are many defects in tetrazole synthesis and vivo metabolism. Therefore, we felt quite encouraged to find some proper acidic heterocyclic groups which maintain the same oral bioavailability to replace the tetrazole. In the present paper, we applied the bioisostere and combination principle, in accordance with the results of computer modeling of molecular, to modify the lead structural of terazole in sartan compounds reported. We turned our attention to replace the tetrazole ring with imidazole rings, chloro-imidazole, imidazoline, traizole ring and combinated them with benzimidazoles derivatives which have antagonistic activity for angiotensin II to design and synthesize a series of Ang II receptor antagonists contaning imidazole ring, chloro-imidazole, imidazoline or traizole ring. In addition, activity tests in vivo and in vivo had shown that imidazoline derivatives display almost equivalent activity with the reference drug, but imidazole derivatives, chloro-imidazole, triazole derivatives were weak or non-performance of the hypotensive activity. We believe that the imidazoline derivative type Ang II receptor antagonists can build a foundation for the development of a novel series of anti-hypertensive drugs.

Quantitative electrochemiluminescence detection of proteins: Avidin-based sensor and tris(2,2 '-bipyridine) ruthenium(II) label

Quantitative electrochemilumineseence (ECL) detection of a model protein, bovine serum albumin (BSA) was achieved via biotin-avidin interaction using an avidin-based sensor and a well-developed ECL system of tris(2,2'-bipyridine) ruthenium(II) derivative as label and tri-n-propylamine (TPA) as coreactant. To detect the protein, avidin was linked to the glassy carbon electrode through passive adsorptions and covalent interaction with carboxylate-terminated carbon nanotubes that was used as binder to immobilize avidin onto the electrode. Then, biotinylated BSA tagged with tris(2,2'-bipyridine) ruthenium(II) label was attached to the prepared avidin surface.

Single-crystal X-ray structure and properties of K-10[Ni-4(H2O)(2)(AsW9O34)(2)]center dot 4H(2)O

The rational synthesis and the structural and magnetic characterization of a nickel cluster are presented. The compound comprises a rhomblike Ni4O16 group encapsulated between two-heptadentate tungstoarsenate ligands [AsW9O34](9-). The crystal structure of K-10[Ni-4(H2O)(2)(AsW9O34)(2)](.)4H(2)O was solved in monoclinic, P2(1)/n symmetry, with a = 12.258(3) Angstrom, b = 21.232(4) Angstrom, c = 15.837(3) Angstrom, beta = 92.05(3)degrees, V = 4119.1(14) Angstrom(3), Z = 2, and R = 0.0862. The crystal structure of the Ni(II) derivative was compared with that of the Cu(II), Zn(II), Co(II) and Mn(II) derivatives. The Ni4O14(H2O)(2) unit in the compound shows no Jahn-Teller distortion. On the other hand, the Ni(II) derivative shows ferromagnetic exchange interactions within the Ni4O16 group (J = 7.8 cm(-1), J' = 13.7 cm(-1)) and an S = 4 ground state, the highest spin state reported in a heteropoly complex. Its redox electrochemistry has been studied in acid buffer solutions using cyclic voltammetry. It exhibited two steps of one-electron redox waves attributed to redox processes of the tungsten-oxo framework. The new catalyst showed an electrocatalytic effect on the reduction of NO2-.

Synthesis, crystal structure, spectroscopy and electroluminescence of zinc(II) complexes containing bidentate 2-(2-pyridyl)quinoline derivative ligands

Three bidentate ligands, 4-phenyl-2-(2-pyridyl)-quinoline (ppq), 6-(carbazol-9-yl)-4-phenyl-2-(2-pyridyl)-quinoline (cpq) and 6-diphenylamino-4-phenyl-2-(2-pyridyl)-quinoline (dpq) and their zinc(II) complexes, have been designed and synthesized. The crystal structure of [Zn(ppq)(2)Cl]PF6 shows that the central zinc atom is coordinated with one chloride and four nitrogen atoms from two ligands. The introduction of an electron-donating substituent such as carbazole or an aromatic amine group at the 6-position of the quinoline moiety can generate colored tunable Zn complexes, and the photoluminescence (PL) wavelength was modulated from 418 nm for [Zn(ppq)(2)Cl]PF6 to 591 nm for [Zn(cpq)(2)Cl]PF6 and 638 nm for [Zn(dpq)(2)Cl]PF6 in CH2Cl2 solution. The electroluminescence spectrum of [Zn(dpq)(2)Cl]PF6 exhibits pure red light emission with the Commission Internationale de L'Eclairage (CIE) coordinates (0.63, 0.36) and a maximum at 648 nm.

Synthesis and evaluation of a thiourea-modified chitosan derivative applied for adsorption of Hg(II) from synthetic wastewater

In this work, a thiourea-modified chitosan derivative (TMCD) was synthesized through two steps, O-carboxymethylated first and then modified by a polymeric Schiff's base of thiourea/glutaraldehyde. The adsorption behavior of mercury (II) ions onto TMCD was investigated through batch method. The maximum adsorption capacity for Hg(II) was found to be 6.29 mmol/g at pH 5.0 and both kinetic and thermodynamic parameters of the adsorption process were obtained. The results indicated that adsorption process was spontaneous exothermic reaction and kinetically followed pseudo-second-order model. The adsorption experiments also demonstrated TMCD had high adsorption selectivity towards Hg(II) ions when coexisted with Cu(II), Zn(II), Cd(II) and Ca(II) in solution and it could be easily regenerated and efficiently reused. (C) 2010 Elsevier B.V. All rights reserved.

Synthesis, spectroscopic and thermal properties of nickel (II)-azo complexes with blue-violet light wavelength

A novel azo dye containing isoxazole ring and beta-diketone derivative (TIAD) and its two nickel (II) complexes (Ni (II)-ETIAD and Ni (II)-HTIAD) were synthesized in order to obtain a blue-violet light absorption and better thermal stability as a promising organic storage material for next generation of high density digital versatile disc-recordable (HD-DVD-R) systems that uses a high numerical aperture of 0.85 at 405 nm wavelength. Their structures were confirmed on the basis of elemental analysis, MS, FT-IR, UV-Vis and magnetic data. Their solubility in 2,2,3,3-tetrafluoro-1-propanol (TFP) and absorption properties of thin film were measured. The difference of absorption maximum from the complexes to their ligands was discussed. In addition, the TG analysis of the complexes was also determined, and their thermal stability was evaluated. (C) 2004 Elsevier Ltd. All rights reserved.

Determination of isocyanates by capillary electrophoresis with tris(2,2 '-bipyridine) ruthenium(II) electrochemiluminescence

CE with tris(2,2'-bipyridyl) ruthenium(II) (Ru(bpy)(3)(2+)) electrochemiluminescence (ECL) detection for the quantitative determination of isocyanates was first reported. Hexamethylene diisocyanate (HDI) and hexyl isocyanate (HI) were used as the model analytes. Commercially available N,N-diethyl-N'-methylethylenediamine was used as the derivatization reagent. It has both a secondary amine group and a tertiary amine group. The secondary amine group can quantitatively react with isocyanate group, and the tertiary amine group can react with Ru(bpy)(3)(2+) to produce strong ECL signal for sensitive detection. The derivatization reaction was almost instantaneous and is much faster than other reported derivative reactions using other derivative reagents.

The first liquid crystalline phthalocyanine derivative capable of edge-on alignment for solution processed organic thin-film transistors

Tetraoctyl-substituted vanadyl phthalocyanine (OVPc4C8) as a new NIR-absorbing discotic liquid crystalline material can form highly ordered thin films with edge-on alignment of the molecules and molecular packing mode identical to that in the phase II of OVPc for solution processed OTFTs with mobility up to 0.017 cm(2) V-1 s(-1).

Molecular orientation of copper phthalocyanine derivative ins copper phthalocyanine-Fe2O3 nanoparticles alternating LB films

Copper phthalocyanine-Fe2O3 nanoparticles alternating thin films were fabricated by Langmuir-Blodgett technique. Molecular orientation of [4-(4'-benzyloxy phenyl sulfonyl)phenoxy]-tris-4-(2,4-di-t-phenoxy) phthalocyanine copper (II) in its alternating LB films, deposited at different conditions,was studied by polarized UV-Vis spectra. The tilt extent of the copper phthalocyanine molecule omits LB films increases with the surface pressure of the subphase increasing on the same subphase, or with Fe2O3 concentration decreasing at the same pressure. The orientation of the copper phthalocyanine derivative is important for the gas-sensing properties. The bigger the tilt extent of the phthalocyanine molecule is, the greater the sensitivity of the film is.

DETERMINATION OF THE MOLECULAR-ORIENTATION OF A PHTHALOCYANINE DERIVATIVE IN A LANGMUIR-BLODGETT-FILM BY POLARIZED UV VIS SPECTRA

Langmuir-Blodgett (LB) films of (p-carboxyphenoxy)-tri(2,4-di-tert-pentyl phenoxy)phthalocyanine copper(II) (asyCuPc) are prepared; the associated forms of the compound in chloroform solution and the particular orientation of asyCuPc molecular macrocycles in LB films is determined by polarized UV-VIS.