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Prediction, Synthesis and Antigenicity of the Antigenic Peptides of 2.kDa Glutathione S-Transferasc of Schistosoma Japonicum (Sj2.)

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Chinese Chemical Letters 1999年第1期10卷 27-28页

作者： Jia Xi XU Meng Shen CAI(college of chemistry and{2. engineering, peking university, beijing 100871)(School of Pharmaceutical Sciences, beijing Medical university. beijing 100083) Coll. of Chem. and Molec. Eng. Peking University Beijing 100871 China School of Pharmaceutical Sciences Beijing Medical University Beijing 100083 China

Six antigenic peptides of 2. kDa glutathione S-transferase of Schistosoma japonicum(Sj2.) have been predicted according to their hydrophilicity, flexibility. accessibility. chargedistribution and β -turn in the secondary structure by the determination of its primary structure andsynthesized by solid phase method. All of them showed antigenicity with anti-schistosomajaponicum immunoglobulin polyclonal antibody, anti-Sj-lgG PcAb by Dot-ELISA. Three of themshowed good antigenicity. They would serve as candidates of synthetic anti-schistosomal vaccine.

关键词： SchistosomajQPonicum glutathione S-transferase antigenic peptide peptide vaccine.

Mechanism of Dealumination of NaY Zeolite with Oxalic Acid

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Chinese Chemical Letters 1998年第8期9卷 789-790页

作者： Hui LIU Xing Yun LIU Xuan Wen LI Xiao Jie XU(college of chemistry and{2. engineering, peking university, beijing 100871) peking Univ Coll Chem & Mol Engn Beijing 100871 Peoples R China

Dealuminated Y zeolite with high crystallinity is obtained from NaY zeolite by treatment with oxalic acid in a buffering system. The effect of dealumination conditions on the degree of dealumination and the crystallin... 详细信息

关键词： NaY zeolite oxalic acid dealumination mechanism

Study on Bicoordination Chiral Inducement Catalysis of (R)-4-Thiazolidinecarboxylic Acid

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Chinese Chemical Letters 2004年第12期15卷 1419-1422页

作者： Hui WANG Wei Wei PEI Guo Bin SUN Wei Ping YE college of chemistry and{2. engineering, peking university, beijing 100871 chemistry and molecular{2. Peking UniversityBeijing 100871

The bicoordination chiral inducement catalysis of (R)-4-thiazolidinecarboxylic acid inthe enantioselective borane reduction of prochiral ketones has been studied. The fact that theabsolute configuration of the main product can be changed by simply using different operationmethods was firstly verified. And the reason of bicoordination chiral inducement was discussed.

关键词： Bicoordination chiral inducement (R)-4-thiazolidinecarboxylic acid.

Systematic study of the transfer of amino acids across the water/1,2.dichloroethane interface facilitated by dibenzo-18-crown-6

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Science China chemistry 2004年第1期47卷 24-33页

作者： CHEN Yong, YUAN Yi, ZHANG Meiqin, LI Fei, SUN Peng, GAO Zhao & SHAO YuanhuaState Key Laboratory of Electroanalytical chemistry, Changchun Institute of Applied chemistry, Chinese Academy of Sciences, Changchun 13002., China {2. of chemistry and molecular engineering, peking university, beijing 100871, China Lab. of Electroanalytical Chem. Changchun Inst. of Appl. Chem. Chinese Acad. of Sci. Changchun 130022 China Coll. of Chem. and molecular Eng. Peking Univ. Beijing 100871 China

Facilitated ion transfer reactions of 2. amino acids with dibenzo-18-crown-6 (DB18C6) at the water/1,2.dichloroethane (W/DCE) interfaces supported at the tips of micro- and nano-pipets were investigated systematically using cyclic voltammetry. It was found that there were only 10 amino acids, that is, Leu, Val, lie, Phe, Trp, Met, Ala, Gly, Cys, Gin (in brief), whose protonated forms as cations can give well-defined facilitated ion transfer voltammograms within the potential window, and the reaction pathway was proven to be consistent with the transfer by interfacial complexation/dissociation (TIC/TID) mechanisms. The association constants of DB 18C6 with different amino acids in the DCE (β0), and the kinetic parameters of reaction were evaluated based on the steady-state voltammetry of micro- or nano-pipets, respectively. The experimental results demonstrated that the selectivity of complexation of protonated amino acid by DB18C6 compared with that of alkali metal cations was low, which can be attributed to the vicinal effect arising from steric hindrance introduced by their side group and the steric bulk effect by lipophilic stabilization. Moreover, the association constants and the standard rate constants for different amino acids showed good correlations with their hydrophobicity (π), except Gly and Met, which inferred that the selectivity of such heterogeneous complex reaction for different amino acids with DB18C6, was not only affected by discrimination in binding these ions to the crown ether macro-cycle, but also significantly modified by the ion transfer Gibbs energy which was closely related to the structure of the transferred ions, protonated amino acids.

关键词： micro-/nano-pipet, water/1,2.dichloroethane interface, facilitated ion transfer, cyclic voltammetry, amino acid.

Reinvestigation on the Reaction of Salicylic Chloride with Salicylic Amide and X-ray Crystal Structure of a New Macrocyclic Polyester

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Chinese Journal of Structural chemistry 2003年第5期22卷 512-516页

作者： DU Da-Ming② CHEN Xiao HUA Wen-Ting JIN Xiang-Lin (Key Laboratory of Bioorganic chemistry and molecular{2. of Ministry of Education, college of chemistry and molecular{2., peking university, beijing 100871, China) Key Laboratory of Bioorganic chemistry and molecular{2. of Ministry of Education College of Chemistry and Molecular Engineering Peking University

The reaction of salicylic chloride and salicylic amide at 170 ℃ gave benzoxazine and a new macrocyclic polyester 3, whose crystal structure has been determined by single-crystal X-ray diffraction analysis. Compound 3: C2.H16O8, Mr = 480.41, monoclinic, space group P2./n, a = 15.353(3), b = 14.196(3), c = 2..147(4) ? b = 103.32.3), V = 4485(2. ?, Z = 8, F(000) = 1984, Dc = 1.42. g/cm3 and m = 0.106 mm-1. The final R = 0.0535 and wR = 0.12.5 for 7903 observed reflections (I ≥ 2.I)). In the asymmetric unit of the compound there exist two independent molecules which are connected by weak aromatic CH…O hydrogen bonding between C(47)?H(47) and atom O(7) of the carbonyl group.

关键词： salicylic chloride salicylic amide polyester macrocycle crystal structure

A thin-layer spectroelectrochemical study of 3,3',5,5'-tetramethylbenzidine at SnO_2.F film optically transparent electrode

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Science China chemistry 2004年第4期47卷 267-275页

作者： JIAO Kui1, YANG Tao2.& NIU Shuyan1,2.1. college of chemistry and{2. engineering, Qingdao university of Science and Technology, Qingdao 2.6042. China 2. college of chemistry and Chemical engineering, Ocean university of China, Qingdao 2.6003, China Correspondence should be addressed to Jiao Kui 1. college of chemistry and{2. engineering Qingdao University of Science and Technology 266042 Qingdao China 2. college of chemistry and Chemical{2. Ocean University of China 266003 Qingdao China

The electrooxidation of 3,3′,5,5′-tetramethylbenzidine (TMB) is dependent on the pH value of Britton-Robinson (B-R) buffer solution. In this work, the electrooxidation behavior of TMB was investigated with a SnO2.F film optically transparent thin-layer spectroelectrochemical cell. TMB underwent one two-electron electrooxidation process in the pH range from 2.0 to < 4.0, and two successive one-electron electrooxidation processes in the pH range from 4.0 to < 7.0 in the B-R buffer solution. At pH 6.5, the electrooxidative product of TMB generated a subsequent chemical reaction to yield an azo compound. Several spectroelectrochemical techniques, such as thin-layer cyclic voltammetry, thin-layer cyclic voltabsorptometry, thin-layer potential-controlled electrolysis absorptometry, thin-layer single-potential-step chronoabsorptometry, thin-layer dou-ble-potential-step chronoabsorptometry, thin-layer single-potential-step open-circuit relaxation chronoabsorptometry, were applied to this investigation. The formal potential E0’ and the electron transfer number corresponding to the electrooxidation of TMB in B-R buffer solution, and the reaction rate constant of the subsequent chemical reaction were determined.

关键词： 3,3′,5,5′-tetramethylbenzidine tin oxide film optically transparent electrode thin-layer spectroelectro-chemistry electrooxidation

“LIVING”/CONTROLLED RADICAL POLYMERIZATION OF ETHYL METHYLACRYLATE WITH 2.2.-AZOBISISOBUTYRONITRILE/FERRIC CHLORIDE/TRIPHENYLPHOSPHINE INITIATION SYSTEM

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Chinese Journal of Polymer Science 2000年第2期18卷 149-153页

作者： Xiao-ping Chen Kun-yuan Qiu Department of Polymer Science and engineering, college of{2., peking university, beijing 100871, China peking Univ Coll Chem Dept Polymer Sci & Engn Beijing 100871 Peoples R China

'Living'/controlled radical polymerization of ethyl methacrylate (EMA) was carried out with a 2.2.-azobisisobutyronitrile (AIBN)/ferric chloride (FeCl_3)/triphenylphosphine (PPh_3) initiation system at 85℃. Thc numberaverage molecular weight (M_n) increases linearly with monomer conversion and the rate of polymerization is first order withrespect to monomer concentration. The M_w of PEMA ranges from 3900 to 17600 and the polydispersity indices are quitenarrow (1.09～1.2.). The conversion can reach up to～100% and M_w of the polymers obtained is close to that designed. Thepolymerization mechanism belongs to the reverse atom transfer radical polymerization (ATRP). The polymer was end-functionalized by chlorine atom, which acts as a macroinitiator to proceed extension polymerization in the presence ofCuBr/bipy catalyst system via an ATRP process. The presence of ω-chlorine in the PEMA obtained was identified by ~1H-NMR spectrum.

关键词： 'Living'/controlled radical polymerization Reverse ATRP Ethyl methacrylate AIBN/FeCl_3/PPh_3 Bulk polymerization

Structural Design and Property Characterization of Bi-functional Photorefractive Polymer

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Chinese Chemical Letters 1999年第8期10卷 667-670页

作者： Yi Wang CHEN Yuan Kang HE Hui Ying CHEN Feng WANG Qi Huang GONG (college of chemistry and{2. engineering, peking university. beijing 100871)(Physical Department. peking university. beijing 100871) beijing Univ Coll Chem & Mol Engn Beijing 100871 Peoples R China beijing Univ Dept Phys Beijing 100871 Peoples R China

A novel bi-functional photorefractive acrylate polymer with pendant carbazolyl groups and azo derivatives as side chains was synthesized. Photorefractive experiments showed a high two-beam coupling gain coefficient of... 详细信息

关键词： acrylate polymer bi-functional polymer photorefractive material

Density functional theory study of the magnetic properties of rare earth complexes:the magnetic coupling mechanism in Y~Ⅲ and Gd~Ⅲ complexes with nitronyl nitroxide

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Science China chemistry 2009年第11期52卷 1961-1968页

作者： REN Jie1,2.WANG BingWu1 & CHEN ZhiDa1 1 beijing National Laboratory for molecular Sciences,State Key Laboratory of Rare Earth Materials{2. and Applications,college of{2. and molecular engineering,peking university,beijing 100871,China 2.college of Science,Hebei university of Science and Technology,Shijiazhuang 050018,China 1. beijing National Laboratory for molecular Sciences State Key Laboratory of Rare Earth Materials Chemistry and Applications College of Chemistry and Molecular Engineering Peking University Beijing 100871 China 2. college of Science Hebei University of Science and Technology Shijiazhuang 050018 China

The magnetic coupling interactions of the nitronyl nitroxide radicals bound to diamagnetic(YⅢ) and paramagnetic(GdⅢ) rare earth ions in two model magnetic systems based on novel rare earth organic radical complexes Ln(hfac)3(NITPhOCH3)2.Ln=YⅢ 1,GdⅢ 2.hafc = hexafluoroacetylacetonate;NIT-PhOCH3 = 4'-methoxyo-phenyl-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide) have been investigated by density functional theory(DFT).The magnetic coupling mechanisms were also explored from the viewpoint of molecular orbital and spin density *** calculations show that the empty 4d-orbitals of YⅢ and 5d-orbitals of GdⅢ play an important role in the antiferromagnetic coupling between the two nitronyl nitroxide radical ligands,and that the ferromagnetic coupling between the GdⅢ ion and the radical magnetic centers can be attributed to the nearly complete localization of the isotropic 4f-shell and singly occupied magnetic orbital(π) of the nitronyl nitroxide.

关键词： magnetic coupling density functional theory rare earth ion gadolinium(Ⅲ) complexes yttrium(Ⅲ) complexes