TD-DFT Study on the Electronic Spectrum Properties of 2,7′-(Ethylene)-bis-8-hydroxyquinoline and Its Derivatives

The structures of 2,7＇-（ethylene）-bis-8-hydroxyquinoline and its derivatives were optimized at the ground states using ab initio HF and B3LYP methods. At the same time, the molecular structures of the first singlet excited state for 2,7＇-（ethylene）-bis-8-hydroxyqulnoline and its derivatives were optimized by CIS/6-31G（d）. The absorption and emission spectra based on the above structures were obtained by the time-dependent density functional theory （TD-DFT） by the B3LYP method with the 6-31G（d） basis set. The calculated results of luminescence originate from the electronic transition from the hydroxphenol ring of 8-hydroxyquinoline A to the pyridine ring of 8-hydroxyquinoline B. Their luminescence wave bands can be tuned by different substituents on the ligand of 8-hydroxyquinoline.

The adsorption and corrosion inhibition of 8-hydroxy-7-quinolinecarboxaldehyde derivatives on C-steel surface in hydrochloric acid

The protection influence of 8-hydroxy-7-quinolinecarboxaldehyde derivatives against C-steel corrosion was studied in 2 mol·L^(-1)HCl solutions at 30 °C. Measurements were conducted under various experimental conditions using weight loss, potentiodynamic polarization, electrochemical impedance spectroscopy(EIS) and electrochemical frequency modulation(EFM) techniques. These studies have shown that 8-hydroxy-7-quinolinecarboxaldehyde derivatives are very good "green", mixed-type inhibitors. Corrosion rates obtained from both EFM and EIS methods are comparable with those recorded using Tafel extrapolation method, confirming validation of corrosion rates measured by the latter. The inhibitive action of these 8-hydroxy-7-quinolinecarboxaldehyde derivatives was discussed in terms of blocking the electrode surface by adsorption of the molecules through the active centers contained in their structures following Langmuir adsorption isotherm. Quantum chemical method was also employed to explore the relationship between the inhibitor molecular properties and its protection efficiency.

Thermochemical Study on Coordination Complex of Samarium with Salicylic Acid and 8-Hydroxyquinoline

The coordination complex Sm（C7H5O2）2·（C9H6NO）, synthesized from the reaction of samarium chloride sixhydrate with salicylic acid and 8-hydroxyquinoline, was characterized with IR, elemental analysis, molar conductance, and thermogravimatric analysis. The standard molar enthalpies of solution of [ SmCl3·6H2O （s） ], [ 2C7H6O3 （s） ], [ C9H7NO （ s ） ] and [ Sm （C7H5O3） 2·（ C9H6NO ） （ s ） ] in the calorimetric solvent were determined with the solution-reaction isoperibol calorimeter at 298.15 K to be △sHm^- [ SmCl3·6H2O （s）, 298.15 K ] = - 103.98 ± 0.04 kJ·mol^-1, △sHm^- [2 C7H6O3 （s）, 298.15 K] = 16.35±0.14 kJ·mol^-1,△sHm^-[C9H7NO （s）, 298.15 K] = -6.11±0.08 kJ·mol^-1 and △sHm^-[Sm（C7H5O3）2·（C9H6NO） （s）, 298.15 K] = - 130.08 ± 0.04 kJ·mol^-1, respectively. The enthalpy was determined to be △rHm^- = 89.59 ±0.18 kJ·mol^-1 for the reaction SmCl3·6H2O（s） ＋ 2C7H6O3（s） ＋ C9H7NO（s） = Sm （C7H5O3） 2·（C9H6NO） （ s ） ＋ 3HCl （g） ＋ 6H2O （ l ）. According to the above results and the data given in literature and through Hess＇ law, the standard molar enthalpy of formation of Sin（ C7H5O3 ）2·（C9H7NO）（s） was estimated to be △rHm^- [ Sm （C7H5O3）2·（C9H6NO） （s）, 298.15 K] = - 2055.9 ± 3.03 kJ·mol^-1.

Crystal Structure and Characterization of a Binuclear Cd(Ⅱ) Quaternary Coordination Complex [Cd_2(phen)_2Q_2(BP)]_n(phen=1,10-Phenanthroline,BP = Biphenyl-4,4'-dicarboxylic acid,Q=8-Hydroxyquinoline Anion)

The structure of a binuclear cadmium（Ⅱ） quaternary complex, [Cd2（phen）2- Q2（BP）]n 1 （phen = 1,10-phenanthroline, BP = biphenyl-4,4′-dicarboxylic acid, Q = 8-hydroxy- quinoline-anion）, has been determined by X-ray crystallography and characterized by elemental analysis, IR spectrum and thermogravimetric analysis. It crystallizes in the monoclinic system, space group P21/n with a = 13.1906（18）, b = 10.9623（15）, c = 16.947（2）A, β = 111.3430（10）°, V = 2282.5（5）A^3, Z = 4, Mr = 556.85, Dc = 1.620 g/cm^3, F（000） = 1116,μ= 0.994 mm^-1 and S = 1.056. In the structure, 1D chains are connected via biphenyl-4,4′-dicarboxylic acid, 8-hydroxy quinoline anion and binuclear cadmium atoms into an infinite 1-D molecular chain architecture. Via aryl ring π-π stacking interactions a supramolecular structure is formed in 1.

Synergistic extraction of praseodymium with 2-ethylhexyl phosphonic acid mono-2-ethylhexyl ester and 8-Hydroxyquinoline

The synergistic extraction of Pr^3＋ from hydrochloric medium using mixture of 2-ethylhexyl phosphonic acid mono- 2-ethylhexyl ester （P507, HL） and 8-Hydroxyquinoline （HQ） in heptane was investigated. The effect of equilibrium of aqueous acidity on extraction of Pr^3＋ was discussed. The effect of extractant concentraction, different diluents, equilibrium time and acetate ion concentration oil extraction reaction were also studied. With a method of double-logarithmic slope, composition of the extracted species on 2-ethylhexyl phosphonic acid mono-2-ethylhexyl ester and 8-Hydroxyquinoline was derived. The result shows that the synergistic extraction system not only overcomes emulsification of 8-Hydroxyquinoline, but also shows perfect capacity of synergistic extraction. The largest synergistic enhancement factor can be calculated to be 5.49 at pH 3.6 for Pr^3＋.

Theoretical Study on Electronic and Charge Transfer Properties of Oligo[8]thiophene and Its Circular,Hooped,and Helical Derivatives

The novel linear, circular, hooped, and helical molecules based on oligo[8]thio- phene were theoretically studied for the applications of charge transfer devices. To investigate the influence of topology for oligo[8]thiophene derivatives, the geometry structures, frontier molecular orbital （FMO） energies, charge transport properties, and stability property were predicted by density functional theory methods. The calculated results reported herein show that the oligo[8]thiophene derivative with linear structure has smaller energy gap, and fused oligo[8]thiophene derivative with circular structure has the smallest reorganization energy among the designed molecules. We have also studied the stability properties of the designed molecules, and oligo[8]thiophene derivatives are more stable tharJ the fused oligo[8]thiophene derivatives.

Bipolar resistive switching based on bis(8-hydroxyquinoline) cadmium complex:Mechanism and non-volatile memory application

Stable and persistent bipolar resistive switching was observed in an organic diode with the structure of indium-tin oxide （ITO）/bis（8-hydroxyquinoline） cadmium （Cdq2）/Al. Aggregate formation and electric field driven trapping and detrapping of charge carriers in the aggregate states that lie in the energy gap of the highest occupied molecular orbital （HOMO） and the lowest unoccupied molecular orbital （LUMO） of the organic molecule were proposed as the mechanism of the observed bipolar resistive switching, and this was solidly supported by the results of AFM investigations. Repeatedly set, read, and reset measurements demonstrated that the device is potentially applicable in non-volatile memories.

A Hydrogen Bond Stabilized 3D Network Built from Pyrazine-2,3,5,6-tetracarboxylic Acid and 8-Hydroxyquinoline

8-Hydroxyquinoline salt of pyrazine-2,3,5,6-tetracarboxylic acid [HQ]2[H2pztc]· 2H2O （1） was prepared and characterized by single-crystal X-ray diffraction, NMR, IR, TGA, elemental analysis and fluorescent measurements. Compound 1 crystallizes in orthorhombic, space group Pbcn with a = 9.953（3）, b = 15.966（3）, c = 16.081（5） A, V = 2555.5（13） A3, Z = 4, μ = 0.122 mm^-1, Dc = 1.514 Mg/m3, T= 296（2） K, C26H22N4O12, Mr = 582.48, F（000） = 1208, S = 1.006, R = 0.0448 and wR = 0.1149. Compound 1 has a three-dimensional （3D） network, in which pyra- zine-2,3,5,6-tetracarboxylic acids build up two-dimensional （2D） sheets and 8-hydroxyquinoline cations and water molecules act as pillars to connect the 2D sheets into an extended 3D network through strong intermolecular hydrogen bonding and π…π stacking interactions. Especially, a very short O-H…O hydrogen bond （O…O 2.470（2） A） between two neighboring [H2pztc] anions was observed.

Synthesis and Structural Characterization of [Co(Q)_2(H_2O)_2](Q=8-Hydroxyquinoline Ion)

The single crystal of bi（8-hydroxyquinoline） bihydrated cobalt （Ⅱ） complex, [ Co（Q）2 （H2O2 ] （Q = 8-hydroxyquinoline ion）, has been synthesized by general method and structurally characterized by single crystal X-ray diffraction. Crystal data： C18H16CoN2O4, monoclinic, C2/c, α = 1.336 2（4） nm, b = 0.941 2（3） nm, c = 1.354 3（4） nm, β= 109.672（4）°, Z = 4. In the complex, Co（ Ⅱ ） ion is six-coordinated, forming a distorted octahedron. H-bonding and π-π stacking interaction play a significant role to form and stabilize the three-dimensional structure.

8-羟基喹啉衍生物作为潜在的艰难梭菌抗生素的设计、合成和活性评价

目的 艰难梭菌感染(CDI)目前治疗措施主要包括抗生素疗法、粪菌移植疗法等,其治疗后存在较高的复发率,需寻求一种更有效的替代疗法。方法 本研究基于有前景的8-羟基喹啉骨架,设计、合成了一系列8-羟基喹啉衍生物。结果 针对艰难梭菌的活性测试表明,多数分子对艰难梭菌具有良好的抑菌作用,其中化合物6f显示出较强的杀伤艰难梭菌活性。结论 本研究发现了新型具有抗艰难梭菌的8-羟基喹啉衍生物,可作为良好的先导化合物进一步研发。

Preparation and Characterization of Carboxyl Functionalized Fluorescent Mesoporous Silica Nanoparticles Containing 8-Hydroxyquinolinate Zinc Complexes

Fluorescent mesoporous silica nanoparticles functionalized with carboxyl group(Znq-CMSCOOH) were successfully synthesized by in situ formation route of 8-hydroxyquinolinate zinc complexes in channels of mesoporous silica nanoparticles and post-grafting of carboxyl group on the surface. Moreover,the particle size and structural properties of Znq-CMS-COOH were characterized by transmission electron microscopy(TEM),field emission scanning electron microscopy(FE-SEM),dynamic light scattering(DLS),Fourier transform infrared spectroscopy(FT-IR),UV-vis spectrometer, fluorescence spectrometer and nitrogen adsorption-desorption measurements. The obtained results suggest that the Znq-CMS-COOH presents the uniform spherical shape with the mean diameter of about 85 nm and the obvious wormhole arrangement mesoporous. In addition, the Znq-CMS-COOH possesses green fluorescence with the emission peaks at 495 nm. So the Znq-CMS-COOH, which is beneficial to further modification and tracing, might be a great potential carrier for applying in drug delivery system in the future.

Effect of caffeic acid derivatives on polychlorinated biphenyls induced hepatotoxicity in male mice

Chronic exposure to coplanar polychlorinated biphenyls（PCBs）,a potent inducer of toxic reactive oxygen species（ROS）,in the environment and food can cause liver diseases.It remains unknown whether caffeic acid derivatives（CADs） exerted protective effect on PCB-induced hepatotoxicity.We sought to evaluate the activities of 3CADs on PCB169-induced oxidative stress and DNA damage in the liver.Male ICR mice were administered with1 μmol/mL PCB169 at 5 mL/kg body weight for 2 weeks.The mice were given CADs by gastric gavage for 3weeks.We found that PCB169 decreased the growth rate and reduced the levels of superoxide dismutase（SOD）,glutathione（GSH） and GSH peroxidase（GPx）.It increased the liver weight,malondialdehyde（MDA）and 8-hydroxy-2＇-deoxyguanosine（8-OHdG） levels and CYPlAl activity in the liver tissues and plasma of mice（P〈0.05）.Pretreatment of mice with CADs restored the above parameters to normal levels.There was a synergistic protective effect between CADs in preventing MDA and 8-OHdG formation and inducing CYPlAl and phase II metabolism enzyme（SOD,GPx） activities（P〈0.05）.In conclusion,PCB169 induced hepatotoxicity and pretreatment with CADs had synergistic protective effects on liver damage.

Expression of Pigment Epithelium-derived Factor in Bladder Tumour Is Correlated with Interleukin-8 yet Not with Interleukin-1α

Pigment epithelium-derived factor （PEDF） is an antiangiogenic factor which is effective in tumour inhibition in a variety of tumours and has not yet been studied in bladder tumour before. In this study the expression of PEDF, interleukin-1α （IL-1α） and -8 （IL-8） in bladder tumours was investigated. Immunohistochemistry was performed on 64 bladder tumour and 23 normal uroepithelium samples. Expression change of the factors was compared with clinicopathological parameters. Correlations between PEDF, IL-1α and IL-8 were analyzed. None of the factors was in relation to gender, tumour occurrence, and size or onset pattern. PEDF （P=0.014） and IL-1α （P=0.049） expression was down-regulated with grade progression. PEDF expression was lower in normal uroepithelium than in papillary urothelial neoplasm of low malignant potential （PUNLMP） （P=0.000） and carcinoma （P=0.009） whilst IL-1α （P=0.000 and P=0.000 respectively） and IL-8 （P=0.000 and P=0.023 respectively） expression was higher in the same grouping. PEDF expression had a negative correlation with IL-8 in PUNLMP （P=0.049, r=-0.578） as well as in tumour grouping （P=0.033, r=-0.276）. Deranged expressional change of PEDF, IL-1α and IL-8 could be in relation to loss of differentiation from normal uroepithelium to papillary lesion and eventually to carcinoma.

Enzymatic Synthesis of a CCK-8 Tripeptide Derivative

The enzymatic synthesis of CCK-8 tripeptide derivative Phac-Met-Asp(OMe)-Phe-NH2 is reported. Starting with Phac-Met-OCam, we have successfully synthesized the target tripeptide with three free or immobilized enzymes, ?chymotrypsin, papain and thermolysin in reasonable yields. The key steps in this synthesis were the coupling of Phac-Met-OCam and H-Asp(OMe)2 to form Met-Asp peptide bond catalyzed by ?chymotrypsin and the selective hydrolysis of -ester of Phac-Met-Asp(OMe)2 catalyzed by papain.

Synthesis and Crystal Structure of a Novel Calix[8]arene Ester Derivative

The synthesis and crystal structure of a novel calix[8]arene ester are reported herein. The calix[8]arene ester derivative has been characterized by IR, NMR and X-ray crystal analysis. The X-ray structure analysis revealed that the 8 phenolic hydroxy groups of the calix[8]arene have been substituted by 4 diethyl dibromomalonate molecules with each two adjacent hydroxy oxygen atoms attached to a bridge diethyl malonate.

Upregulation of stromal cell-derived factor-1 alpha/CXCR4 axis-induced migration of human neural progenitors by tumor necrosis factor-alpha and interleukin-8

BACKGROUND： Studies of several animal models of central nervous system diseases have shown that neural progenitor cells （NPCs） can migrate to injured tissues. Stromal cell-derived factor 1 alpha （SDF-la）, and its primary physiological receptor CXCR4, have been shown to contribute to this process. OBJECTIVE： To investigate migration efficacy of human NPCs toward a SDF-1α gradient, and the regulatory roles of tumor necrosis factor-α （TNF-α） and interleukin-8 （IL-8） in SDF-1α/CXCR4 axis-induced migration of NPCs. DESIGN, TIME AND SETTING： An in vitro, randomized, controlled, cellular and molecular biology study was performed at the Laboratory of Department of Cell Biology, Medical College of Soochow University between October 2005 and November 2007. MATERIALS： SDF-1α and mouse anti-human CXCR4 fusion antibody were purchased from R＆D Systems, USA. TNF-αwas purchased from Biomyx Technology, USA and IL-8 was kindly provided by the Biotechnology Research Institute of Soochow University. METHODS： NPCs isolated from forebrain tissue of 9 to 10-week-old human fetuses were cultured in vitro. The cells were incubated with 0, 20, and 40 ng/mL TNF-α, or 0, 20, and 40 ng/mL IL-8, for 48 hours prior to migration assay. For antibody-blocking experiments, cells were further pretreated with 0, 20, and 40 μg/mL mouse anti-human CXCR4 fusion antibody for 2 hours. Subsequently, the transwell assay and CXCR4 blockade experiments were performed to evaluate migration of human NPCs toward a SDF-1α gradient. Serum-free culture medium without SDF-1α served as the negative control. MAIN OUTCOME MEASURES： The transwell assay was performed to evaluate migration of human NPCs toward a SDF-1α gradient, which was blocked by fusion antibody against CXCR4. In addition, CXCR4 expression in human NPCs stimulated by TNF-α and IL-8 was measured by flow cytometry. RESULTS： Results from the transwell assay demonstrated that SDF-1α was a strong chemoattractant for human NPCs （P 〈 0.01）, and 20 ng/mL produced the highest levels of migration. Anti-human CXCR4 fusion antibody significantly blocked the chemotactic effect （P 〈 0.05）. Flow cytometry results showed that treatment with TNF-α and IL-8 resulted in increased CXCR4 expression and greater chemotaxis efficiency of NPCs towards SDF-1α（P 〈 0.01）. CONCLUSION： These results demonstrated that SDF-la significantly attracted NPCs in vitro, and neutralizing anti-CXCR4 antibody could block part of this chemotactic function. TNF-α and IL-8 increased chemotaxis efficiency of NPCs towards the SDF-1αgradient by upregulating CXCR4 expression in NPCs.

含氯不对称配体8-羟基喹啉铝配合物电子和光谱性质的TDDFT研究

以含时密度泛函理论(TDDFT)B3LYP方法通过电子结构计算研究了含氯不对称配体8-羟基喹啉铝配合物AlQ(ClQ)_2的吸收和发射光谱性质.计算表明,第一激发态与基态结构变化主要集中在单一含氯配体中,与mer-AlQ_3相比,前线占有轨道离域程度变大而未占据轨道则定域化程度提高.最大吸收主要来自配体内电荷转移跃迁,电荷从苯酚环和氯向含氮的吡啶环跃迁.电子陷入态计算表明,抽取电子能量比AlQ_3相应值略大,与实验结果一致.

8-羟基喹啉衍生物及其金属配合物的合成与光致发光特性

设计合成了三种新型的8-羟基喹啉衍生物配体:5-[(4-E-苯乙烯基)-苯甲亚胺基]-8-羟基喹啉(1),5-[(4-溴-2-氟)-苯甲亚胺基]-8-羟基喹啉(2)和N-乙基-3-[2-(8-羟基喹啉基)-乙烯基]咔唑(3),以及它们相应的金属配合物,产物经质谱(MS)、元素分析(EA)、红外光谱(IR)、紫外光谱(UV)、核磁共振氢谱(1HNMR)进行表征,并测定了它们的荧光性质.结果与8-羟基喹啉比较表明,5位和2位取代8-羟基喹啉衍生物的荧光发生了明显的红移.同时测定了配合物(3)2Zn的荧光寿命,结果表明,N-乙基-3-[2-(8-羟基喹啉基)-乙烯基]咔唑锌配合物表现出较长的荧光寿命.

8-羟基别二氢葛缕醇及其衍生物的合成与驱避活性研究

以α-蒎烯（1）为原料，合成了8-羟基别二氢葛缕醇（3）及其甲酸酯（4）、乙酸酯（5）和丙酸酯（6），并用IR、MS、^1H NMR及^13C NMR分析对它们的结构进行了表征。按照国家标；隹GB 17322．10—1998测定了这4个化合物对白纹伊蚊的驱避活性。结果显示：化合物3对白纹伊蚊没有驱避活性，与之结构及其类似的对盖烯二醇等已被以往的研究证明具有驱避活性，因此极性官能团和手性碳原子位置可能是影响驱避活性的重要因素；衍生物6对白纹伊蚊没有驱避活性，这可能与其羰基部分太大有关，在目前的萜类驱避剂中尚极少见丙酸酯类；衍生物5具有一定的驱避活性，质量分数为20％时，对白纹伊蚊的驱避时间接近4h；衍生物4的驱避效果最好。质量分数为20％时，对白纹伊蚊的驱避时间可以达到7～8h，与避蚊胺（DETA）的驱避效果相同。

凝血酶对人重组内皮细胞衍生IL—8融合蛋白转换作用

本文报道利用基因工程技术在大肠杆菌中表达出入内皮细胞衍生IL-8(EDhIL-8)与细菌蛋白lacZ 的融合蛋白lac-hIL-8和lac-T-hIL-8,后者含有一个人工合成凝血酶切点。EDhIL-8上含有一个凝血酶切点,凝血酶可以将lac-hIL-8及以前表达的MS2-hIL-8水解为有生物活性的天然IL-8,而对含有两个凝血酶切点的lac-T-hIL-8无水解作用。这些结果提示凝血酶的功能不仅依赖于所识别的氨基酸,而且依赖于这些氨基酸形成的构象。