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Chinese Journal of Structural chemistry 2010年第10期29卷 1513-1518页

作者：邱东方赵茜刘克成郭应臣冯玉全 College of chemistry and pharmacy Engineering Nanyang Normal University

Two novel mono-nuclear zinc（Ⅱ） complexes with oligoaniline-functionalized terpyridine ligands have been synthesized and verified by 1H-NMR,13C-NMR,Elemental Analysis （EA） and X-ray Diffraction （XRD）. The UV-vis spectra show the ligand-centered （LC） π-π＊ transitions and intra-ligand charge transfer （1ILCT） transitions,and the 1ILCT band red-shifts with the increasing number of aromatic amine groups in the ligands. Complex [Zn（L1）2]（PF6）2 with an aromatic amine group in ligand shows a strong emission peak at 523 nm in the MeCN solution at 293 K and a blue-shifted band at 517 nm in the alcoholic glass at 77 K. However,for complex [Zn（L2）2]（PF6）2 containing aniline dimer modified ligand,no apparent emission can be observed in the MeCN solution at room temperature due to a PET non-radiative decay pathway. Both of them show multiplicate redox processes based on oligoaniline and terpyridine units. The shifts of redox potentials also reflect the D-A interactions between the oligoaniline units and [Zn（TPY）2]2＋ core.

关键词： oligoaniline terpyridine zinc(II) crystal structure spectroscopic property,electrochemical behavior

Solvothermal Synthesis, Structure and the Secondorder NLO Properties of a Novel Non-metal 3-D Borophosphate:（NH4）2[B2P2O8（OH）2]

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Chinese Journal of Structural chemistry 2019年第11期38卷 1909-1915页

作者： FENG Yu-Quan ZHAO Qian BI Dong-Qin College of chemistry and pharmacy Engineering Nanyang Normal University

A new non-metal 3-D borophosphate compound formulated as(NH4)2[B2P2O8(OH)2](1)has been synthesized by a solvothermal method and characterized by elemental analysis,energy-dispersive X-ray spectroscopy(EDS),IR spectrum and single-crystal X-ray *** borophosphate(NH4)2[B2P2O8(OH)2]crystallizes in the cubic system,space group P213 with Z=2,a=b=c=7.586(4)?,V=436.6(4)?3,Mr=281.64,Dc=2.127 g/cm^3,λ=0.71073?,μ=0.551 mm^-1,F(000)=284,R=0.0277 and wR=0.0758 for 262 observed reflections with I>2σ(I)and S=*** structure is constructed by the connection of PO4 and BO3(OH)tetrahedra to form a 3-D anionic framework containing 4-and 8-membered rings(MRs),with two NH4+cations located in the channels of the 8-membered *** N–H…O hydrogen bonds are observed in its packing structure and enhanced the stability of crystal *** addition,its thermal stability,UV spectrum and second-order NLO properties have been also investigated.

关键词： solvothermal synthesis borophosphate UV spectrum second-order NLO properties

Syntheses and Crystal Structures of Two New Nickel(Ⅱ) Complexes with Salicylidene-2-ethanolamine

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Chinese Journal of Structural chemistry 2012年第3期31卷 339-344页

作者：陈书阳刘若雨郭应臣冯玉全赵晓梅 College of chemistry and pharmacy Engineering Nanyang Normal University

Two new Schiff base complexes of nickle（Ⅱ） [C18H20NiN2O4]·1.5H2O（1） and [C18H20N2NiO4]·H2O（2） were synthesized and characterized by elemental analysis,IR,UV-Vis and X-ray crystal structure *** 1 and 2 crystallize in the orthorhombic *** 1：space group Pbcn with a = 12.8591（19）,b = 14.779（2）,c = 19.749（3） ,V = 3753.3（10） 3,C18H23N2NiO5.5,Mr = 414.07,Z = 8,Dc = 1.445 g/cm3,μ = 1.067 mm-1,F（000） = 1712,S = 1.037,the final R = 0.0741 and wR = 0.2101 for 4353 observed reflections（I 〉 2σ（I）） and R = 0.1157 and wR = 0.2380 for all *** 2：space group P21 with a = 9.4673（17）,b = 11.559（2）,c = 16.347（3） ,V = 1788.9（6） 3,C18H22N2NiO5,Mr = 405.07,Z = 4,Dc = 1.497 g/cm3,μ = 1.116 mm-1,F（000） = 840,S = 1.085,the final R = 0.0330 and wR = 0.0869 for 3151 observed reflections（I 〉 2σ（I）） and R = 0.0362 and wR = 0.0887 for all *** Ni atom of 1 and 2 is six-coordinated with two nitrogen atoms and four oxygen atoms from two salicylidene-2-ethanolamine ligands yielding a distorted octahedral *** structure is observed in the packing diagram of *** thermal stability of complex 2 is also studied.

关键词： nickle complex synthesis crystal structure

Boron Oxide Glasses and Nanocomposites: Synthetic, Structural and Statistical Approach

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Journal of Materials Science & Technology 2017年第6期33卷 535-540页

作者： Hristo Hristov Miroslava Nedyalkova Sergio Madurga Vasil Simeonov Faculty of chemistry and pharmacy University of Sofia Physical chemistry Department and Research Institute of Theoretical and Computational chemistry (IQTCUB) of the University of Barcelona (UB)

Three different precursors of boron-aqua and glycerol solutions of boric acid and ethanol solution of trimethyl borate were used for the preparation of organic–inorganic advanced materials. The films and bulk materials samples were heat treated at 100, 400, 800？C for 2 h. The hybrid samples were stable and transparent until 100？C. The further increase of temperature to 400？C led to destruction of samples, and at 800？C they were molten. The structural changes during the pyrolysis were studied by Fourier transform infrared spectroscopy, differential thermal analysis, and X-ray diffraction. Details of surface morphology were observed by scanning electron microscopy. The obtained BO_3 and BO_4 groups were identified in the molten materials after pyrolysis. The quantities and order of borate structural units as well as residual carbon in the networks depended on boron precursor type. PVA/PEG/B_2O_3 hybrid materials were proved to be appropriate precursors for synthesizing borate and carboborate glass and carbon/borate glass nanocomposites. To access the impact of the experimental conditions on the structural changes of the nanocomposites, cluster analysis of the IR-spectral data was used as a classification method.

关键词： Organic–inorganic hybrid materials Borate glass Nanocomposites Cluster analysis

Inclusion complexes of cefuroxime axetil with β-cyclodextrin:Physicochemical characterization, molecular modeling and effect of Larginine on complexation

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Journal of Pharmaceutical Analysis 2016年第5期6卷 300-306页

作者： Sarika Sapte Yogesh Pore Department of Pharmaceutical chemistry Government College of Pharmacy

The inclusion complexes of poorly water-soluble cephalosporin, cefuroxime axetil(CFA), were prepared with β-cyclodextrin(βCD) with or without addition of L-arginine(ARG) to improve its physicochemical properties. We also investigated the effect of ARG on complexation efficiency(CE) of βCD towards CFA in an aqueous medium through phase solubility behaviour according to Higuchi and Connors. Although phase solubility studies showed AL(linear) type of solubility curve in presence and absence of ARG, the CE and association constant(Ks) of βCD towards CFA were significantly promoted in presence of ARG,justifying its use as a ternary component. The solid systems of CFA with βCD were obtained by spray drying technique with or without incorporation of ARG and characterized by differential scanning calorimetry(DSC), X-ray powder diffractometry(XRPD), scanning electron microscopy(SEM), and saturation solubility and dissolution studies. The molecular modeling studies provided a better insight into geometry and inclusion mode of CFA inside βCD cavity. The solubility and dissolution rate of CFA were significantly improved upon complexation with βCD as compared to CFA alone. However, ternary system incorporated with ARG performed better than binary system in physicochemical evaluation. In conclusion, ARG could be exploited as a ternary component to improve the physicochemical properties of CFA via βCD complexation.

关键词： Cefuroxime axetil β-cyclodextrin Inclusion complex Molecular modeling Physicochemical characterization

Hydrothermal Synthesis,Crystal Structure and Fluorescence Spectrum Studies of a Novel Supramolecular Compound {[2-(2-Pyridyl)benzimidazoleH_2]_2·[BiCl_6]·Cl}

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Chinese Journal of Structural chemistry 2010年第5期29卷 811-815页

作者：邱东方李玉玲王宏伟郭应臣 College of chemistry and pharmacy Engineering Nanyang Normal University

A novel supramolecular compound,{[2-（2-pyridyl）benzimidazoleH2]2·[BiCl6]·Cl},was synthesized by the hydrothermal reaction of o-phenylenediamine and α-pyridinecarboxylic acid with BiCl3 in 6.0 mol·L-1 HCl solution,and characterized by elemental analysis,IR,X-ray single-crystal diffraction and photoluminescence *** crystal （C24H22N6Cl7Bi,Mr= 851.61） belongs to the triclinic system,space group P1 with a =7.2887（18）,b =9.548（2）,c= 12.469（3）,α=85.306（4）,β=82.814（4）,γ=71.349（4）°,Z=1,V=814.9（3）3,Dc=1.735 g/cm3,μ（MoKα）=6.007 mm-1,F（000）=410,R=0.0307 and wR=*** bismuth ion and six chlorine ions construct a distorted octahedral *** three-dimensional supramolecular network is built from electrostatic attractions,hydrogen bonds and π-π interaction between the BiCl6 anion,Cl anion and [2-（2-pyridyl）benzimidazoleH2] *** photoluminescence spectroscopy study shows that the title compound has a blue fluorescent emission at 450 nm in the solid state.

关键词： 2-(2-pyridyl)benzimidazole supramolecular compound hydrothermal synthesis,crystal structure photoluminescence spectroscopy

Cysteine proteases as therapeutic targets:does selectivity matter? A systematic review of calpain and cathepsin inhibitors

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Acta Pharmaceutica Sinica B 2015年第6期5卷 506-519页

作者： Marton Siklos Manel Ben Aissa Gregory R.J.Thatcher Department of Medicinal chemistry and Pharmacognosy University of Illinois College of Pharmacy

Cysteine proteases continue to provide validated targets for treatment of human *** neurodegenerative disorders,multiple cysteine proteases provide targets for enzyme inhibitors,notably caspases,calpains,and *** reactive,active-site cysteine provides specificity for many inhibitor designs over other families of proteases,such as aspartate and serine;however,a)inhibitor strategies often use covalent enzyme modification,and b)obtaining selectivity within families of cysteine proteases and their isozymes is *** review provides a general update on strategies for cysteine protease inhibitor design and a focus on cathepsin B and calpain 1 as drug targets for neurodegenerative disorders;the latter focus providing an interesting query for the contemporary assumptions that irreversible,covalent protein modification and low selectivity are anathema to therapeutic safety and efficacy.

关键词： Cysteine protease Calpain Cathepsin Enzyme inhibitors Neurodegeneration Alzheimer’s disease

Fluorescence triggered by ligand-protein hydrophobic interaction

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Science China chemistry 2013年第11期56卷 1667-1670页

作者： LIU ZhenZhen DU LuPei LI MinYong Department of Medicinal chemistry School of PharmacyShandong University

Hydrophobic fluorescence:Tan and his colleagues recently introduced a brand new chemotype of environment-sensitive fluorescent turn-on probes to detect the hydrophobic ligand-binding domain by using SBD *** design strategy described in this report generalized the environment sensitivity turn-on mechanism to recognize a specific protein,which provides a robust breakthrough for interchanging fluorescence in conventional small-molecule fluorescent imaging.

关键词： non-enzyme protein environment-sensitive probe turn-on fluorescence SBD fluorophore

Studies on the Conformations and Hydrogen Bonding of ACE Inhibitory Tripeptide VEF by All-atom Molecular Dynamics Simulations and Molecular Docking

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Chinese Journal of Structural chemistry 2017年第2期36卷 189-196页

作者：齐春艳张荣黄国栋吴文娟 Lab of Physical chemistry School of Pharmacy Guangdong Pharmaceutical University

Molecular dynamic simulations and molecular docking are performed to study the conformations and hydrogen bonding interactions of ACE inhibitory tripeptide VEF. Intramolecular distance, radius of gyration, solvent-accessible surface, and root-mean-square deviations are used to characterize the properties of VEF in aqueous solution. The VEF molecule is highly flexible in water and conformations can shift between the extended and folded states. The VEF molecule exists in extended state mostly in aqueous solution and the conformations bonded with ACE are also the extended ones. The findings indicate that MD simulations have a good agreement with the molecular docking analysis.

关键词： Hydrogen bonding characterize conformation amide accessible folded bonds bonded catalyze

HYDRATION AND PHASE SEPARATION OF TEMPERATURE-SENSITIVE WATER-SOLUBLE POLYMERS

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Chinese Journal of Polymer Science 2011年第1期29卷 13-21页

作者： Fumihiko Tanaka Tsuyoshi Koga Hiroyuki Kojima Francoise M.Winnik Department of Polymer chemistry Graduate School of EngineeringKyoto University Department of chemistry and Faculty of pharmacy University of Montréal

Collapse of a poly（N-isopropylacrylamide）（PNIPAM） chain upon heating and phase diagrams of aqueous PNIPAM solutions with very fiat LCST phase separation line are theoretically studied on the basis of cooperative dehydration （simultaneous dissociation of bound water molecules in a group of correlated sequence）, and compared with the experimental observation of temperature-induced coil-globule transition by light scattering methods. The transition becomes sharper with the cooperativity parameter σ of hydration. Reentrant coil-globule-coil transition in mixed solvent of water and methanol is also studied from the viewpoint of competitive hydrogen bonds between polymer-water and polymer-methanol. The downward shift of the cloud-point curves （LCST cononsolvency） with the mole fraction of methanol due to the competition is calculated and compared with the experimental data. Aqueous solutions of hydophobically-modified PNIPAM carrying short alkyl chains at both chain ends （telechelic PNIPAM） are theoretically and experimentally studied. The LCST of these solutions is found to shift downward along the sol-gel transition curve as a result of end-chain association （association-induced phase separation）, and separate from the coil-globule transition line. Associated structures in the solution, such as flower micelles, mesoglobules and higher fractal assembly, are studied by USANS with theoretical modeling of the scattering function.

关键词： Cooperative dehydration LCST phase separation Poly(N-isopropylacrylamide) Cononsolvency Coil-globule transition Flower micelle.