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Self-assembly of Hydrazide-based Heterodimers Driven by Hydrogen Bonding and Donor-Acceptor Interaction

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Chinese Journal of chemistry 2006年第9期24卷 1200-1208页

作者：冯代军王鹏李小强黎占亭 Shanghai institute of Organic chemistry Chinese Academy of Sciences Shanghai 200032 China

A new series of hydrogen bonding-driven heterodimers have been self-assembled in chloroform from hydrazide-based monomers. Additional intermolecular donor-acceptor interaction between the electron-rich bis（p-phenylene）-34-crown-10 unit and the electron-deficient naphthalene diimide unit has been utilized to increase the stability of the dimmers, and pronounced cooperativity of the two discrete non-covalent forces to stabilize the dimer has been revealed by the quantitative ^1H （2D） NMR and UV-Vis experiments.

关键词： hydrazide heterodimer self-assembly hydrogen bonding donor-acceptor interaction

Novel immonium type peptide coupling reagent: 5-(1H-benzotriazol-1-yloxy)-3,4-dihydro-l-methyl 2H-pyrrolium hexachloroantimonate (BDMP )

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Chinese Journal of chemistry 2000年第1期18卷 85-93页

作者：李鹏徐杰诚 Shanghai institute of Organic chemistry Chinese Academy of Sciences Shanghai 200032 China

A novel immonium type coupling reagent, 5-(1H-benzotria-zol-1-yloxy )-3,4-dihydro-1-methyl 2H-pyrrolium hexachlo-roantimonate (BDMP) has been designed, synthesized and u-tilized to synthesize oligopeptides and biologically active pep-tide both in solution and solid phase with satisfactory yield, low racemization and fast reaction rate. The estimation of racemization and the influence of several reaction parameters were studied by HPLC method using the model reaction: Z-Gly-Phe-OH + Val-OMe·HCl→Z-Gly-D/L-Phe-Val-OMe. It was shown that the reactivity of BDMP was much higher and the racemization was much lower than those of HOBt-based 'onium' reagents, even though its analogues BOMI. To further verified the effectiveness of BDMP, Leu-enkephalin was synthesized both in solution and solid phase using BDMP as coupling reagent. The proposed mechanism was also speculated.

关键词： BDMP peptide coupling reagent immonium salt racemization reactivity

RADIATION CROSSLINKING OF BRANCHED POLY (VINYL ACETATE)

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Chinese Journal of Polymer Science 1985年第4期3卷 362-366页

作者：张万喜庄国庆孙家珍 Changchun institute of Applied chemistry Academia Sinica Changchun

In the present work, radiation crosslinking of different branched poly （vinyl acetate） have beemstudied and the validity of the relationship between sol fraction and radiation dose: R(S+S1/2=1/U1qo+p′o/qoRβto bran... 详细信息

关键词： VINYL ACETATE RADIATION CROSSLINKING OF BRANCHED POLY

Study on the stannous halides promoted addition of 1,1,1-trichloro-2,2,2-trifluoroethane to aldehydes and the chemical transformation thereof

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Chinese Journal of chemistry 1994年第2期12卷 183-189页

作者： HU, Chang-Ming CHEN, JianShanghai institute of Organic chemistry, Chinese Academy of Sciences, Shanghai 200032, China Shanghai institute of Organic chemistry Chinese Academy of Sciences Shanghai 200032 China

Promoted by stannous salts, 1,1,1-trichloro-2,2,2-trifluoroethane reacts readily with aliphatic, aromatic, and α, β-unsaturated aldehydes giving the corresponding alcohols bearing a CF3CCl2-moiety in good to excelle... 详细信息

关键词： 1,1,1-Trichloro-2,2,2-trifluoroethane aldehydes stannous halides addition Jones oxidation ketones.

Synthesis of Ag_2S nano-sized clusters and their chemical sensitizations in AgCl cubic and {100} tabular microcrystal imaging systems

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Science China chemistry 2005年第6期48卷 516-522页

作者： LI Zhi1, ZHENG Tong1, CHEN Lijuan1, PENG Bixian1 & YANG Li2 1. Technical institute of Physics and chemistry, Chinese Academy of Sciences, Beijing 100101, China 2. Beijing Satellite Manufacturing Factory, Beijing 100080, China Technical institute of Physics and chemistry Chinese Academy of Sciences Beijing 100101 China

In recent years much attention has been devoted to AgCl emulsion owing to its se-rial advantages and inimitable potential. But in the research of this emulsion a thorny problem remains unsolved till now, which is the improvement in sensitivity is always accompanied with high fog density. In this work 5 nm Ag2S particles were prepared and used as novel sensitizers in AgCl cubic and {100} tabular microcrystal emulsions. The novel sensitizer shows an effective sensitizing ability for silver chloride emulsion, and it is superior to the traditional Na2S2O3 sensi-tizer because by using it comparatively high sensitivity can be obtained with lower fog density. So the above sensitizing problem is going to be effectively solved. To discover the evolution mechanism of the sensitizer clusters and explain their excellent sensitizing properties, diffuse reflectance spectroscopy (DRS) was used as a probe on the AgCl microcrystal surface.

关键词： silver sulfide, nano-sized, silver chloride {100} tabular microcrystal, chemical sensitization.

γ-Fe_2O_3:A magnetic separable catalyst for synthesis of 5-substituted 1H-tetrazoles from nitriles and sodium azide

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Chinese Chemical Letters 2010年第9期21卷 1029-1032页

作者： Gang Qi Yong Dai Department of chemistry and Biology Yancheng Institute of Technology Yancheng 224051 China

An efficient route for the synthesis of 5-substituted 1H-tetrazole via[2＋3]cycloaddition of nitriles and sodium azide is reported usingγ-Fe2O3 nanoparticles as a magnetic separable *** optimized conditions,the moderate to good yields（71-95%） can be *** catalyst can be easily separated by a magnet and reused for several circles.

关键词： γ-Fe2O3:Magnetic separable catalyst Tetrazole [2+3]Cycloaddition

The Production of Monoclonal Antibody to Androstenedione and the Effect of Passive Immunization on Xinjiang Fine-Wool Sheep With It

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Science China chemistry 1993年第6期36卷 693-701页

作者：吕兆启马纪萱周常文王云芳王军向际尧高远曾宪黎 Xinjiang institute of chemistry Academia Siniea Urumqi 830011 PRC

Five hybridomas stably secreting monoclonal antibodies (McAbs) to androstenedione were prepared by using artificially synthesized androstenedione-11α-succinyl conjugate with bovine serum albumin (BSA) as antigen. These McAbs showed slightly high cross-reactivity with testosterone (8.1—12.3%) and estrone (0.8—2.5%) and high affinities ranging from 2.0×10~7 to 2.8×10~8 L/M. They were all of the IgG_1 subclass. Xinjiang finewool ewes which were passively immunized with McAbs had higher circulating levels of progesterone (P) and luteinizing hormone (LH) than those of control ewes in two oestrous cycles and these changes led to increased ovulation rate and twin lambs born in young ewes.

关键词： androstenedione monoclonal antibody Xinjiang fine-wool sheep twin ovulations twin lambs born.

Prediction on amphiphilicity of hypocrellin derivatives

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Science China chemistry 2002年第3期45卷 251-256页

作者：谢杰马江华赵井泉 Center for Molecular Sciences Institute of Chemistry Chinese Academy of Sciences Beijing China

Hypocrellins are most suitable for photodynamic therapy (PDT) of the diseases occurring in the superficial layer, such as microvascular diseases, because of their special absorption spectral properties. However, hypocrellins and most of their derivatives are basically lipophilic, while the hydrophilic derivatives lose the PDT activity in vivo. Therefore, the key problem for practical application of PDT of microvascular diseases focuses on finding the derivatives which possess optimized amphiphilicity. Herein, we developed a theoretical method to estimate the amphiphilicity of a molecule by the calculated average polarity. Compared with the experimentally measured results, the method is proved to be applicable. Based on the computation and available experimental results, it can be concluded that the derivative must have the polarities around 0.22 for optimized amphiphilicity.

关键词： hypocrellin derivative prediction of molecular amphiphilicity.

Brφnsted acidic ionic liquid catalyzed highly efficient synthesis of chromeno pyrimidinone derivatives and their antimicrobial activity

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Chinese Chemical Letters 2012年第9期23卷 1015-1018页

作者： Janardhan Banothu Rajitha Bavanthula Department of chemistry National Institute of TechnologyWarangal 506004APIndia

A series of 8,9-dihydro-2-（2-oxo-2H-chromen-3-yl）-5-aryl-3H-chromeno[2,3-d]pyrimidine-4,6（5H^7H）-diones （Sa-j）have been synthesized by the reaction of 2-amino-5,6,7,8-tetrahydro-5-oxo-4-aryl-4H-chromene-3-carbonitrile （4a-j） with couma- rin-3-catboxylic acid under neat conditions employing Brnsted acidic ionic liquid （4-sulfobutyl）tris（4-sulfophenyl）phosphonium hydrogen sulfate as catalyst. Structures of all the compounds were established on the basis of analytical and spectroscopic data. All the compounds were evaluated for their in vitro antimicrobial activity against different bacterial and fungal strains.

关键词： Antimicrobial activity Ionic liquid Neat conditions 8,9-Dihydro-2-(2-oxo-2H-chromen-3-yl)-5-aryl-3H-chromeno[2,3-d]pyrimidine- 4,6(5H,7H)-dione