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In vitro reassembly of nuclear envelopes and organelles in Xenopus egg extracts

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Cell Research 2006年第7期16卷 632-640页

作者： Ping Lu~1 Hui Zheng~2.Zhonghe Zhai ~1college of Life Sciences ~2.nstitute of {3. Medicine,{2. beijing 100871,china college of Life Sciences Peking University Beijing China Institute of molecular Medicine Peking University Beijing China

We reconstituted bilayer nuclear membranes,multilayer membranes,and organelles from mixtures of Xenopus laevis eggextracts and demembranated Xenopus sperm *** proportions of the cytosolic and vesicular fractions from theeggs were used in the reconstitution mixtures.A cytosol:vesicle ratio of 10:1 promoted reassembly of the normal bilayernuclear membrane with inserted nuclear pore complexes around the decondensed Xenopus sperm chromatin.A cytosol:vesicle ratio of 5:1 caused decondensed and dispersed sperm chromatin to be either surrounded by or divided by unusualmultilayer membrane structures with inlaid pore complexes.A cytosol:vesicle ratio of 2.5:1 promoted reconstitution ofmitochondria,endoplasmic reticulum networks,and Golgi *** reassembly of the endoplasmic reticulumand Golgi apparatus,vesicular fragments of the corresponding organelles fused together and changed their shape to formflattened cisternae,which were then stacked one on top of another.

关键词： cell-free system endoplasmic reticulum Golgi apparatus mitochondria nuclear reconstitution Xenopus egg extracts

Approach to synthesis of novel chiral 3.chloro-2.5H)- furanone and its application in asymmetric reactions

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Chinese Science Bulletin 2000年第8期45卷 711-716页

作者： HUANG Hui & CHEN Qinghua1. Department of chemistry, Tonghua Teacher’s college, Tonghua 13.002. {2. 2. Department of chemistry, beijing Normal university, beijing 100875, {2. Department of chemistry Tonghua Teacher’s College Tonghua China Department of chemistry Beijing Normal University Beijing China

The synthetic method of the novel chiral synthon, 5-/-menthyloxy-3.chloro-2.(5H)-furanone 5a and its application in asymmetric reactions were investigated. 5a is easily obtained in highly optical purity, and acts as a stable acceptor of Michael addition with oxygen nucleophiles in tandem double Michael addition / internal nucieophilic substitution to offer the spiro-cyclopropane derivative containing four stereogenic centers 8, which it is difficult to obtain by routine methods. The synthetic methods for 5a and 8 are reported in detail and the new compounds are identified on the basis of their analytical data and spectroscopic data, such as UV, IR, H NMR,13.C NMR, MS and elementary analysis. The absolute configuration of the interesting spiro-cyclopropanes, spiro [1-chloro-4-(/-menthyloxy)-5-oxo-6-oxa-biscyclo[3.1.0]hexane-2.3.(4’-/-menthyloxy-5’-/-menthyloxy- butyrolactone)] 8 was established by X-ray crystallography. This result can provide important synthetic strategy in synthesis of some complex

关键词： new chiral synthon. 5-l-menthyloxy-3.chloro-2.(5H)-furanone absolute configuration spiro-cyclopropane derivative containing multiple chiral centers.

An efficient chiral synthesis of (R)-N-[3.acetyl-4-(2.hydroxy-3.isopropylamino-propoxy)phenyl]-butanamide with high enantioselectivity

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Science china chemistry 2009年第8期52卷 1216-1219页

作者： WANG NaiXing1,2.& TANG XinLiang1,3.1 Technical Institute of Physics and chemistry,Chinese Academy of Sciences,beijing 100080,{2. 2.college of chemistry and Chemical engineering,Graduate university of Chinese Academy of Sciences,beijing 100049,{2. 3.School of Chemical engineering and Environment,beijing Institute of Technology,beijing 100081,{2. Technical Institute of Physics and chemistry Chinese Academy of Sciences Beijing China college of chemistry and Chemical {2. Graduate University of Chinese Academy of Sciences Beijing China School of Chemical engineering and Environment Beijing Institute of Technology Beijing China

R-Enantiomer of the β-receptor antagonist N-[3.acetyl-4-(2.hydroxy-3.isopropylamino-propoxy)phenyl] butanamide with high enantioselectivity was synthesized from cheap starting materials and enantiopure chiral reagent through an efficient,convenient and practical synthetic *** product was detected by 1H NMR,13. NMR,and MS,and the enatiomeric excess was determined by chiral HPLC analysis using a chiracel AD-H column.

关键词： chiral synthesis enantioselectivity enatiomeric excess chiral HPLC analysis

Theoretical study on thermal decomposition of azoisobutyronitrile in ground state

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Science china chemistry 2004年第5期47卷 373-380页

作者： SUN Chengke1,2. ZHAO Hongmei1 & LI Zonghe1 1. Department of chemistry, beijing Normal {2., beijing 100875, china 2. Department of chemistry, Qujing Normal college, Qujing 655000, china Dept. of Chem. Beijing Normal Univ. Beijing 100875 China Dept. of Chem. Qujing Normal Coll. Qujing 655000 China

The thermal decomposition mechanisms of azoisobutyronitrile (AIBN) in the ground state have been investigated systematically. Based on the potential energy surfaces (PES) of various possible dissociation paths obtained using the semiempirical AM1 method with partial optimization, the density function theory B3.YP/6-3.1G* method was employed to optimize the geometric parameters of the reactants, the intermediates, the products and the transition states, which were further confirmed by the vibrational analysis. The obtained results show that the re- action process of the two-bond (three-body) simultaneous cleavage Me2.CN)C─ N=N─ C(CN)Me2. 2.e2.CN)C?+N2.is much more favorable than the reaction process of the two one- bond asynchronous cleavage Me2.CN)CN=N─C(CN)Me2.? Me2.CN)CN=N?+ Me2.CN)C?? Me2.CN)C?+ N2. It was suggested that the electron shrinking effect of double bond (─N=N─) in AIBN and the stabilities of the Me2.CN)C?radical as well as N2.molecule are main factors of leading to the reaction proceeding in the former pathway. The calculation results were consistent with all the experimental facts.

关键词： azoisobutyronitrile, radicals, thermal decomposition, density function theory (DFT).

Adsorption and corrosion inhibition behavior of imidazole on cobalt electrodes studied by SERS and electrochemical methods

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Science china chemistry 2005年第6期48卷 497-503页

作者： GU Wei1, LIU Guokun2. REN Bin2. WU Deyin2. GU Renao1 & TIAN Zhongqun2.1. Department of chemistry, college of chemistry and Chemical engineering, Suzhou university, Suzhou 2.5006, china 2. State Key Laboratory for Physical chemistry of Solid Surfaces and Department of chemistry, college of chemistry and Chemical engineering, Xiamen university, Xiamen 3.1005, china Department of chemistry College of Chemistry and Chemical Engineering Suzhou University Suzhou China State Key Laboratory for Physical chemistry of Solid Surfaces and Department of chemistry College of Chemistry and Chemical Engineering Xiamen University Xiamen China

The interaction of imidazole with Co electrodes in an electrochemical system was studied by surface-enhanced Raman scattering (SERS) and electrochemical methods. The SER spectra of Co in an imidazole solution as a function of the applied potential were analyzed and the assignment of the Raman bands was made. It was found that there were three kinds of sur-face species on the Co surface in different potential regions and they were interchangeable de-pending on the potential. In a relatively negative potential region (?1.2.to ?0.9 V), imidazole was adsorbed on the surface and its orientation might change from a vertical configuration via the N-end of the pyridine ring to a tilted configuration via the C2.N3.double bond. In a more positive potential region (?0.8 to ?0.7 V), the SERS signal from the adsorbed imidazole weakened and finally disappeared, meanwhile the signal from the Co and imidazole complex strengthened gradually. At the open circuit potential (?0.6 V), we detected very strong bands from the Co ox-ides. By comparing the Tafel curves of the Co electrode in the solution without and with imidazole, we found that imidazole has a marked effect on the corrosion inhibition of the Co electrode. This result demonstrates that we may be able to reveal the complicated interaction of surface species with metal surface at the molecular level by combining the SERS and electrochemical methods.

关键词： cobalt, imidazole, inhibition, surface-enhanced Raman spectroscopy, Tafel plot.

Crystal Structure of Triethyl 6-benzoyl-3.-(4-fluorophenyl)-2.3.3.,4,5,6-hexahydro-5-methyl-1H-pyro〔1,2.a〕〔1,5〕benzodiazepine-1,2.3.tricarboxylate

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Chinese Journal of Structural chemistry 1999年第4期 18-22页

作者： WANG HongZhong\ XU JiaXi\ MI BaoYu\ JIN Sheng* (college of chemistry and molecular engineering, peking university, {2.)

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关键词： crystal structure pyrro1 2.1 5benzodiazepine 1

Role of inositol 1,4,5-trisphosphate receptors in α1-adrenergic receptorinduced cardiomyocyte hypertrophy

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Acta Pharmacologica Sinica 2006年第7期27卷 895-900页

作者： Da-li LUO~(2.3.5) Jian GAO~2.Xiao-mei LAN~3.Gang WANG~4 Sheng WEI~4 Rui-ping XIAO~4 Qi-de HAN~3.0}Department of Pharmacology,School of Chemical Biology & Pharmaceutical Sciences,Capital {3. of Medical Sciences,beijing 100069,{2. 3.Institute of Cardiovascular Science at Health Science Center,peking university beijing 100083.{2. 4 Institute of molecular Medicine and college of Life Science,peking university,beijing 100871,{2. Department of Pharmacology School of Chemical Biology & Pharmaceutical Sciences Capital University of Medical Sciences Beijing China Institute of Cardiovascular Science at Health Science Center Peking University Beijing China Institute of molecular Medicine and college of Life Science Peking University Beijing China

Aim:Intracellular Ca2.plays pivotal roles in diverse cellular functions,includinggene transcription that underlies cardiac remodeling during stress ***,the role of inositol 1,4,5-trisphosphate receptors（IP3.s）in the media-tion of cardiac intracellular Ca2.and hypertrophic growth remains *** with neonatal rat ventricular myocytes suggests that activation of IP3.smay be linked to α1adrenergic receptor（α1AR）increased stereotyped Ca2.sparkoccurrence and global Ca2.***,we hypothesized that Ca2.releasethrough IP3.s was necessary for α1AR-stimulated cardiac ***:We used myoinositol 1,4,5-trisphosphate hexakis（butyryloxymethyl）ester（IP3.M）,a membrane-permeant ester of IP3.to activate IP3.s directly,and Fluo 4/AM tomeasure intracellular Ca2.***:IP3.M(10μmol·L-1)mimicked theeffects of phenylephrine,a selective agonist of α1AR,in increments in local Ca2.spark release（especially in the perinuclear area）and global Ca2.*** importantly,IP3. inhibitors,2.aminoethoxydiphenyl borateand Xestospongin C,abolished the IP3.M-induced Ca2.responses,and signifi-cantly suppressed α1AR-induced cardiomyocyte hypertrophy assayed by cellsize,[3.]leucine incorporation and atrial natriuretic factor gene expression,dur-ing sustained（48 h）phenylephrine ***:These results,therefore,provide cellular mechanisms that link IP3. signaling to α1AR-stimulatedgene expression and cardiomyocyte hypertrophy.

关键词： inositol 1,4,5-trisphosphate receptors Ca2.sparks α1 adrenergic stimulation cardiac hypertrophy

A new method to evaluate force constants from experimental spectral data

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Chinese Journal of chemistry 1994年第5期12卷 403-413页

作者： LI, Le-Min LIU, Yi WANG, Xiu-ZhenDepartment of chemistry, peking university, {2., {3. Department of chemistry Peking University Beijing 100871 China

An iterative procedure is proposed to facilitate the determination of molecular vi-brational force constants from the experimental fundamental frequencies. Proper restrictions are introduced to the force constants based on physical considerations for getting reasonable results. The experimental data of Coriolis coupling coefficients and isotopic frequency shifts are utilized to reduce the uncertainty of the calculated force constants when they are available. A series of various kinds of molecules have been calculated by this method and the results are satisfactory.

关键词： Determination of force constants iterative procedure vibrational spectra fundamental frequencies isotopic frequency shifts Coriolis coupling coefficients.

Synthesis and thermodynamic analysis of nano-La2.3

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Progress in Natural Science:Materials International 2007年第7期17卷 838-844页

作者： Liu Lili~(1,2. Tang Jie~2.Li Yuxiang~1 Zhang Mei~(1**) Wang Xidong~(1,3. (1.Department of Physical chemistry,{3. of Science and Technology {2.,{2. 100083.china 2.National Institute for Materials Science,Segen 1-2.1,Tsukuba 3.5-0047,Japan 3.college of engineering,{2. {3.,{13.,china) Department of Physical chemistry University of Science and Technology Beijing Beijing 100083 China National Institute for Materials Science Segen 1-2-1 Tsukuba 305-0047 Japan college of engineering Beijing University Beijing 100871 China

The thermodynamic parameters of La（NO3.3.nd La（OH）3.re evaluated and the thermodynamics of nano-La2.3.yn- thetic process is *** the base of thermodynamic analysis,La2.3.ano-powders are prepared by the sol-gel method and the experi- ment scheme is designed by an orthogonal *** dry-gelatin is analyzed with differential thermal analysis/thermo-gravimetric analy- sis（TGA-DTA）and X-ray diffraction *** microstructure of nano-La2.3.owders is observed by transmission dectron micro- *** synthetic parameters affecting the average grain size and dispersivity of nano-La2.3.articles are experimentally examined and *** the results indicate that nano-La2.3.articles well-dispersed are obtained and the average grain size is in the range of 2.—50 nm.

关键词： nano-La2.3 sol-gel thermodynamic analysis