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Synthesis of Some Iminosugar.Der.vatives and Evaluation of Their.Biological Activities

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Synthesis of Some Iminosugar Derivatives and Evaluation of T...

中国资源生物技术与糖工程学术研讨会

作者： Xin-ShanYe (The state key laboratory of natural and biomimetic drugs, School of p.ar.aceutical Sciences, peking university, Xue Yuan r. #38, beijing 100083, china)

＜正＞Iminosugar., also called the "sugar.shap.d alkaloids", ar. car.ohydr.te analogues in which the r.ng oxygen has been r.p.aced by nitr.gen and ar. found to be widesp.ead in the p.ants and micr.or.anisms. They ar. fr.quently found to be p.tent inhibitor. of many car.ohydr.te-p.ocessing enzymes involved in imp.r.ant biological *** unique molecules p.omise a new gener.tion of iminosugar.based medicines in a wide r.nge of diseases such as diabetes, vir.l infections, tumor.metastasis, and lysosomal stor.ge disor.er..

关键词：

Some Iminosugar.:Their.Syntheses and Biological Activities

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Some Iminosugars:Their Syntheses and Biological Activities

中国化学会第26届学术年会化学生物分会场

作者： Xin-Shan Ye The state key laboratory of natural and biomimetic drugs, School of p.ar.aceutical Sciences, peking university, Xue Yuan r. #38, beijing 100083, china

Iminosugar., also called the "sugar.shap.d alkaloids", ar. car.ohydr.te analogues in which the r.ng oxygen has been r.p.aced by nitr.gen and ar. found to be widesp.ead in the p.ants and micr.or.anisms. They ar. fr.quently found to be p.tent inhibitor. of many car.ohydr.te-p.ocessing enzymes such as glycosidases involved in imp.r.ant biological systems.[1,2] These unique molecules p.omise a new gener.tion of iminosugar.based medicines in a wide r.nge of diseases such as diabetes, vir.l infections, tumor.metastasis, and lysosomal stor.ge disor.er..[3] However. these iminosugar.der.vatives as immunosup.r.ssive agents ar. less exp.or.d and little is known about their.inhibition effects on immune system r.sp.nses. We descr.be her.in the synthesis of some iminosugar.der.vatives and their.effects on the secr.tion of IL-4 and IFN-gamma fr.m the mouse sp.enocytes.[4,5] Our.r.sults demonstr.te that synthetic iminosugar. may hold the p.tential as new immunosup.r.ssive agents. On the other.hand, some iminosugar.der.vatives p.ssessing p.tential anti-tumor.activities will be also discussed.[6]

关键词： iminosugar car.ohydr.te-based dr.g synthesis

Conver.ence analysis of the adap.ive finite element method with the r.d-gr.en r.finement

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Science china Mathematics 2010年第2期53卷 499-512页

作者： ZHAO XuYing 1, 3 , HU Jun 2,? & SHI ZhongCi 1 1 state key laboratory of Scientific and Engineer.ng Comp.ting, Institute of Comp.tational Mathematics and Scientific/Engineer.ng Comp.ting, Academy of Mathematics and Systems Science, Chinese Academy of Sciences, beijing 100190, china 2 key laboratory of Mathematics and Ap.lied Mathematics (peking university), Ministr. of Education and School of Mathematical Sciences, peking university, beijing 100871, china 3 Gr.duate university of Chinese Academy of Sciences, beijing 100190, china 1. state key laboratory of Scientific and Engineer.ng Comp.ting Institute of Computational Mathematics and Scientific/Engineering Computing Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100190 China3. Graduate University of Chinese Academy of Sciences Beijing 100190 China2. Key Laboratory of Mathematics and Applied Mathematics (Peking University) Ministry of Education and School of Mathematical Sciences Peking University Beijing 100871 China

In this p.p.r. we analyze the conver.ence of the adap.ive confor.ing p.1 element method with the r.d-gr.en r.finement. Since the mesh after.r.fining is not nested into the one befor., the Galer.in-or.hogonality does not hold for.this case. To over.ome such a difficulty, we p.ove some quasi-or.hogonality instead under.some mild condition on the initial mesh (Condition A). Consequently, we show conver.ence of the adap.ive method by establishing the r.duction of some total er.or. To weaken the condition on the initial mesh, we p.op.se a modified r.d-gr.en r.finement and p.ove the conver.ence of the associated adap.ive method under.a much weaker.condition on the initial mesh (Condition B).

关键词： r.d-gr.en r.finement adap.ive finite element method conver.ence non-nested local r.finement

Synthesis of 6-(Br.momethyl)-4-methoxy-5,6,7,8-tetr.hydr.p.r.do-[3,2-d]p.r.midin-2-ol fr.m 6-Methylp.r.midine-2,4-diol

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Chemical r.sear.h in Chinese Univer.ities 2012年第1期28卷 57-60页

作者： LIU Wei-dong2, DENG Xi-ling2, ZHANG Zhi-li2, WANG Xiao-wei2 and LIU Jun-yi1,2 1. state key laboratory of natural and biomimetic Dr.g, 2. Dep.r.ment of Chemical Biology, School of p.ar.aceutical Sciences, peking university, beijing 100191, p. r. china peking Univ Sch Pharmaceut Sci State Key Lab Nat & Biomimet Drug Beijing 100191 Peoples R China peking Univ Sch Pharmaceut Sci Dept Biol Chem Beijing 100191 Peoples R China

6-（Br.momethyl）-4-methoxy-5,6,7,8-tetr.hydr.p.r.do[3,2-d]p.r.midin-2-ol（comp.und 9） was synthe sized fr.m 6-methylp.r.midine-2,4-diol（comp.und 1） thr.ugh the cr.cial step. of 6-methyl alkylating and intr.mo lecular.cyclization. The assignment of the str.ctur. of comp.und 9 was p.r.or.ed by its sp.ctr.l data, 1H NMr. 13C NMr. HMBC, and Hr.S sp.ctr..

关键词： Heter.cycle Car.anion Alkylation r.duction Cyclization

Synthesis and p.op.r.ies of sir.A Incor.0}r.ted with Isonucleosides

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Synthesis and Properties of siRNA Incorporated with Isonucle...

第六届全国化学生物学学术会议

作者： Zhen-jun Yang state key laboratory of natural and biomimetic drugs School of p.ar.aceutical Sciences,peking university,beijing 100191,china

＜正＞r.A inter.er.nce（r.Ai） r.p.esents a p.wer.ul molecular.str.tegy for.inhibition of gene *** p.ocess can be induced by 21-23 nt double-str.nded r.As（dsr.As）,known as small inter.er.ng r.As（sir.As）.These olig...

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Oligosacchar.de Synthesis by p.e-Activation Str.tegy

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Oligosaccharide Synthesis by Pre-Activation Strategy

第五届全国化学生物学学术会议

作者： Xin-Shan Ye The state key laboratory of natural and biomimetic drugs,School of p.ar.aceutical Sciences,peking university,Xue Yuan r.#38,beijing 100083,china

＜正＞Sacchar.de synthesis is a for.idable task to synthetic *** r.cent year. many advances have been made in this ar.a,develop.ent of mor. convenient and efficient str.tegies for.oligosacchar.de synthesis is still in gr.at *** r.cent year.,“p.e-activation”as a new glycosylation ap.r.ach has r.ceived incr.asing ***-activation str.tegy has some advantages over.the r.utine glycosylation op.r.tions,since it does not r.quir. the tuning of the building blocks in an ar.ed-disar.ed *** have established the concep. of iter.tive one-p.t synthesis of oligosacchar.des based on p.e-activation *** concep. r.fer. to that glycosyl donor. can be p.e-activated,which gener.tes a r.active inter.ediate in the absence of the accep.or. After.addition of the second building block to the p.e-activated donor.a disacchar.de will be for.ed with an identical activatable aglycon at the r.ducing ***,by r.p.ating this p.ocess in the same r.action flask,r.p.d constr.ction of oligosacchar.des can be *** also found that

关键词： car.ohydr.tes p.e-activation synthetic methods

Char.cter.zation of flavonoids in Millettia nitida var. hir.utissima by Hp.C/DAD/ESI-MS^n

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Jour.al of p.ar.aceutical Analysis 2012年第1期2卷 35-42页

作者： Min Ye, Wen-Zhi Yang, Ke-Di Liu, Xue Qiao, Bei-Jia Li, Jun Cheng, Jie Feng, De-An Guo, Yu-Ying Zhao state key laboratory of natural and biomimetic drugs, School of p.ar.aceutical Sciences, peking university, 38 Xueyuan r.ad, beijing 100191, china state key laboratory of natural and biomimetic drugs School of Pharmaceutical Sciences Peking University 38 Xueyuan Road Beijing 100191 China

Millettia nitida var. hir.utissima is a Chinese her.al medicine used for.the tr.atment of gynecological diseases. An Hp.C/DAD/ESI-MSn method was established for.the r.p.d sep.r.tion and char.cter.zation of bioactive flavonoids in M. nitida var. hir.utissima. A total of 32 flavonoids wer. detected, of which 14 comp.unds wer. unambiguously char.cter.zed by comp.r.ng their.r.tention time, UV, and MS sp.ctr. with those of the r.fer.nce standar.s, and the other. wer. tentatively identified based on their.tandem mass sp.ctr.metr. fr.gmentation data obtained in the negative ionization mode on line. Nineteen of these comp.unds char.cter.zed wer. r.p.r.ed fr.m this p.ant for.the fir.t time.

关键词： Hp.C/DAD/ESI-MSn Millettia nitida var. hir.utissima Mass sp.ctr.metr. Flavonoids

Or.er.disor.er.Tr.nsfor.ation for.TiAl with L1_0 Str.ctur. at Stoichiometr.cal Comp.sition

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r.r. Metals 2001年第3期20卷 147-151页

作者： Timothé e Nsongo, Xiaodong Ni,Guoliang Chen,Keh-Minn Chan 1) state key laboratory for.Advanced Metals and Mater.als, university of Science and Technology beijing, beijing 100083, china 2) Faculty of Science (p.ysics Dep.r.ment, p.O. Box 69 Br.zzaville, Univ Sci & Technol beijing State Key Lab Adv Met & Mat Beijing 100083 Peoples R China Fac Sci Dept Phys Brazzaville Rep Congo Univ Sci & Technol beijing Dept Phys Beijing 100083 Peoples R China W Vir.inia Univ Dept Mech & Aerosp Engn Morgantown WV 26506 USA

The embedded atom method (EAM) was used to study the or.er.disor.er.tr.nsfor.ation in gamma -TiAl alloy with L1(0). str.ctur. at stoichiometr.cal comp.sition, and the effect of lattice constants was also investigated. It was found that the gamma -TiAl alloy at stoichiometr.cal comp.sition exhibits a second-or.er.tr.nsition, and the r.lations between lattice constants a, c and the long-r.nge or.er.sigma ar. not linear. The lattice constant a decr.ases wher.as c incr.ases with the incr.ase of the long-r.nge or.er.p.r.meter. In this case the or.er.ng induces the tr.nsfor.ation fr.m cubic to tetr.gonal. The change of the lattice constant dur.ng the or.er.ng p.ocesses can be inter.0}eted in ter.s of bond length.

关键词： or.er.disor.er.tr.nsfor.ation TiAl long-r.nge or.er inter.etallic

Context-awar. end-to-end QoS diagnosis and quantitative guar.ntee based on Bayesian networ.

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The Jour.al of china Univer.ities of p.sts and Telecommunications 2010年第6期17卷 106-112页

作者： LIN Xiang-tao,CHNEG Bo,CHEN Jun-liang,QIAO Xiu-quan state key laboratory of Networ.ing and Switching Technology,beijing university of p.sts and Telecommunications,beijing 100876,china [a] state key laboratory of Networ.ing Switching Technology Beijing University of Posts Telecommunications Beijing 100876 China

To sup.or. quality of ser.ice （QoS） management on cur.ent Inter.et wor.ing with best effor.,we br.ng for.h a systematic ap.r.ach for.end-to-end QoS diagnosis and quantitative guar.ntee. For.QoS diagnosis,we take contexts of a ser.ice into consider.tion in a comp.ehensive way that is r.alized by exp.oiting causal r.lationship. between a QoS metr.c and its contexts with the help.of Bayesian networ. （BN） str.ctur. lear.ing. Context discr.tization algor.thm and node or.er.ng algor.thm ar. p.op.sed to facilitate BN str.ctur. lear.ing. The QoS metr.c is diagnosed to be causally r.lated to its causal contexts,and the QoS metr.c can be quantitatively guar.nteed by its causal contexts. For.quantitative QoS guar.ntee,those causal r.lationship. ar. fir.t modeled quantitatively by BN p.r.meter.lear.ing. Then,the QoS metr.c is guar.nteed to cer.ain value with a p.obability given its causal contexts tuned to suitable values,that is,quantitative QoS guar.ntee is r.ached. Simulations with thr.e sequential stages：context discr.tization,QoS diagnosis and quantitative QoS guar.ntee,on a p.er.to-p.er.（p.p. networ.,ar. discussed and our.ap.r.ach is validated to be effective.

关键词： context context discr.tization QoS qualitative diagnosis QoS quantitative guar.ntee Bayesian networ.