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Diastereoselective Michael Addition of (4'S)-Ethyl-3-(2',2'-Dimethyl-1',3'- dioxolan-4'-yl) acrylate with Furyl Lithium

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Chinese Chemical Letters 2001年第5期12卷 403-406页

作者： dong Mei HAN Xun Tian JIANG Jian Hong CHEN Bin WANG dong lu bai Shanghai Institute of Meteria Medica Shanghai Institutes for Biological SciencesChinese Academy of SciencesShanghai 200031

Michael addition of the chiral alpha,beta -unsaturated ester 2 with furyl lithium proceeded in syn manner with excellent diastereoselectivity. The diastereoselectivity was not affected by the configuration of the doub... 详细信息

关键词： Michael addition configuration determination syn addition.

Stereoselective Synthesis of (6R)-6-(5-Methyl-2-furyl)-2-oxocyclohexanecarboxyl-10', 2'-Sultam

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Chinese Chemical Letters 1999年第9期10卷 733-734页

作者： Xi lu WANG You Hong HU Li Gong OU dong lu bai(Shanghai Institute of Materia Medica. Chinese Academy of Sciences, Shanghai 200031) Shanghai Institute of Materia Medica Chinese Academy of Sciences Shanghai 200031 China

Stereoselective synthesis of sultam 8 was reported. The overall yield in a scLluence of 4steps is 27.5%.

关键词： Stcreoselective. synthesis. sultam. conjugated addition.

An Efficient Cleavage of 1,3-Dioxolane Using ZnCl_2/THF/H_2O

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Chinese Chemical Letters 2000年第2期11卷 95-96页

作者： Li Gong OU dong lu bai (Shanghai Institute of Materia Medica, the Chinese Academy of sciences 294 Taiyuan Road, Shanghai, 200031) Shanghai Institute of Materia Medica Chinese Academy of Sciences 294 Taiyuan Road Shanghai 200031 China

A new. mild and efficient method for the cleavage of 1,3-dioxolane is reported.

关键词： 1,3-Dioxolane ketal deprotection

Studies on the Total Synthesis of Pseudolaric Acid A Stereocontrolled Synthesis of the Seven-membered Lactone

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Chinese Chemical Letters 1999年第4期10卷 281-284页

作者： You Hong HU Li Gong OU Xi lu WANG dong lu bai(Shanghai Institute of Materia Medica,Chinese Academy of Sciences. 294 Taiyuan Road, Shanghai 200031) Shanghai Institute of Materia Medica Chinese Academy of Sciences 294 Taiyuan Road Shanghai 200031 China

The lactone 16 was obtained stereo- and regioselectively by a reaction sequence of 9 steps in 21% overall yield.

关键词： Pseudolaric acid A stereocontrol synthesis seven-membered lactone

Photosynthesis of Tetrahydroprotoberberines with Electron withdrawing Groups on Ring D

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Chinese Chemical Letters 1998年第8期9卷 707-710页

作者： Yong Zhou HU Qi Ting ZHOU dong lu bai(Shanghai Institute of Materia Medica,Chinese Academy of Sciences, 294 Taiyuan Road Shanghai 200031) Shanghai Institute of Materia Medica Chinese Academy of Sciences 294 Taiyuan Road Shanghai 200031 China

A number of tetrahydroprotoberberines with electron-withdrawing groups on ring D have been synthesized via photocyclization of 2-formyl-1-benzylideneisoquinorine enamides as the key step.

关键词： photosynthesis tetrahydroprotoberberines

Polysaccharides from Chinese herbal medicine:a review on the hepatoprotective and molecular mechanism

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Chinese Journal of Natural Medicines 2024年第1期22卷 4-14页

作者： LI Jifeng GUO Haolin dong Ying YUAN Shuo WEI Xiaotong ZHANG Yuxin dong lu WANG Fei bai Ting YANG Yong Dalian Key Laboratory of Chronic Disease Research Center Dalian UniversityDalian 116622China Key Laboratory of Natural Medicines of the Changbai Mountain Ministry of EducationCollege of PharmacyYanbian UniversityYanji 133002China

Polysaccharides,predominantly extracted from traditional Chinese medicinal herbs such as Lycium barbarum,Angelica sinensis,Astragalus membranaceus,Dendrobium officinale,Ganoderma lucidum,and Poria cocos,represent principal bioactive constituents extensively utilized in Chinese *** compounds have demonstrated significant anti-inflammatory capabilities,especially anti-liver injury activities,while exhibiting minimal adverse *** review summarized recent studies to elucidate the hepatoprotective efficacy and underlying molecular mechanisms of these herbal *** underscored the role of these polysaccharides in regulating hepatic function,enhancing immunological responses,and improving antioxidant capacities,thus contributing to the attenuation of hepatocyte apoptosis and liver *** of molecular pathways in these studies revealed the intricate and indispensable functions of traditional Chinese herbal polysaccharides in liver injury ***,this review provides a thorough examination of the hepatoprotective attributes and molecular mechanisms of these medicinal polysaccharides,thereby offering valuable insights for the advancement of polysaccharide-based therapeutic research and their potential clinical applications in liver disease treatment.

关键词： Polysaccharides Hepatoprotective Chinese herbal medicine Mechanism

Microphysical Insights into a Tornadic Supercell from Dual-Polarization Radar Observations in Jiangsu, China on 14 May 2021

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Journal of Meteorological Research 2024年第2期38卷 303-320页

作者： Chao YUAN Yang bai Pengfei SUN Hua bai lu XIA China Meteorological Administration Tornado Key Laboratory Foshan 528315 Institute of Atmospheric Environment China Meteorological AdministrationShenyang 110166 Panjin National Climate Observatory Panjin 124010 Yangzhou Meteorological Bureau of Jiangsu Province Yangzhou 225100 Yichun Meteorological Bureau of Heilongjiang Province Yichun 153000

Tornadoes are incredibly powerful and destructive natural events,yet the microphysical characteristics of the parent storm and its effects on tornadogenesis remain *** study analyzed polarization radar data of a tornadic supercell that occurred in Jiangsu Province of China on 14 May 2021,in comparison with another tornadic supercell and two non-tornadic supercells that occurred in the same region in *** two tornadic supercells exhibited lower differential reflectivity(ZDR)in the hook echo region compared with the non-tornadic supercells,indicating smaller median drop sizes.A distinct increase in ZDR from the melting of frozen hydrometeors,observed between2.5-and 4.0-km altitude in the non-tornadic storms,was absent in the tornadic *** non-tornadic supercells also displayed substantially higher specific differential phase(KDP)below the melting level,likely aroused from enhanced melting and *** findings suggest fundamental microphysical contrasts between tornadic and nontornadic ***,tornadic supercells have smaller droplets and may reduce melting in hook ***,greater separation between the ZDR arc and the KDP foot was observed during *** vertical gradient of KDP related to the cooling pool strength of the hook echo,regulating rear-flank downdraft *** the limited number of cases investigated,the findings of this study indicate that monitoring ZDR,KDP,and drop size distribution trends could assist with tornado prediction and warnings.

关键词： tornado polarimetric radar supercell hook echo drop size distribution

Evaluating CMIP6 models in simulating the North Pacific decadal variability in sea surface salinity

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Science China Earth Sciences 2024年第8期67卷 2661-2680页

作者： Jian CHEN Hailong LIU Pengfei LIN Wenrong bai Chengzu bai lu WANG Institute of Atmospheric Physics Chinese Academy of SciencesBeijing 100029China State Key Laboratory of Geo-Information Engineering Xi’an 710054China Beijing Municipal Climate Center Beijing Meteorological BureauBeijing 100089China Space System Department Equipment Department Beijing 100096China

The North Pacific sea surface salinity(SSS)decadal variability(NPSDV)and its potential forcing were evaluated from 25 coupled models of the Coupled Model Intercomparison Project phase 6(CMIP6)considering the prospects for decadal climate *** results indicated that the CMIP6 models generally reproduced the spatial patterns of *** large standard deviation of the SSS anomaly over the strong current regions,such as the Kuroshio-Oyashio Extension(KOE),North Pacific Current(NPC),California Current System(CCS),and Alaskan Coastal Current(ACC),is reflected in the two leading modes of NPSDV:a dipole with out-of-phase loadings in the KOE-NPC versus CCS-ACC and a monopole with positive loading over the *** order of modes is sensitive to individual models that exhibit discrepancies,especially in temporal phases and power *** autoregressive model of order-1 was used to reconstruct the NPSDV with several forcing *** generally weaker influence of forcings in an autoregressive model of order-1 is partly related to the overestimated response time of NPSDV relative to *** NPSDV variances originate from the persistence of SSS anomalies,but the dominant forcing factors are diverse among *** model diversity for the NPSDV simulation mainly arises from the influence of the tropical El Ni?o-Southern Oscillation through teleconnection on the North Pacific Oscillation or Aleutian Low with timescale ***,models that can reproduce the NPSDV well are not dependent on those with larger impacts from the North Pacific oceanic processes.

关键词： North Pacific Sea surface salinity Decadal variability CMIP6 Leading mode

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On Minor Left Prime Factorization Problem for Multivariate Polynomial Matrices

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Journal of Systems Science & Complexity 2024年第3期37卷 1295-1307页

作者： lu dong WANG Dingkang XIAO Fanghui School of Mathematics Southwest Jiaotong UniversityChengdu 610031China KLMM Academy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190China School of Mathematical Sciences University of Chinese Academy of SciencesBeijing 100049China MOE-LCSM School of Mathematics and StatisticsHunan Normal UniversityChangsha 410081China

A new necessary and sufficient condition for the existence of minor left prime factorizations of multivariate polynomial matrices without full row rank is *** key idea is to establish a relationship between a matrix and any of its full row rank *** on the new result,the authors propose an algorithm for factorizing matrices and have implemented it on the computer algebra system *** examples are given to illustrate the effectiveness of the algorithm,and experimental data shows that the algorithm is efficient.

关键词： Free modules Grobner bases minor left prime(MLP) multivariate polynomial matrices polynomial matrix factorizations