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Copper-Catalyzed Enantioselective Synthesis of α-Hydroxyamine Using Monodentate Phosphoramidites

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有机化学 2004年第Z1期24卷 43-44页

作者： DONG,Lin CUN,Lin-Feng GONG,Liu-Zhu MI,Ai-Qiao JIANG,yao-zhong Key Laboratory of Asymmetric Synthesis and Chirotechnology of Sichuan Province and Union Laboratory of Asymmetric Synthesis Chengdu Institute of Organic Chemistry Chinese Academy of Sciences Chengdu 610041 Key Laboratory of Asymmetric Synthesis and Chirotechnology of Sichuan Province and Union Laboratory of Asymmetric Synthesis Chengdu Institute of Organic Chemistry Chinese Academy of Sciences Chengdu 610041 Key Laboratory of Asymmetric Synthesis and Chirotechnology of Sichuan Province and Union Laboratory of Asymmetric Synthesis Chengdu Institute of Organic Chemistry Chinese Academy of Sciences Chengdu 610041 Key Laboratory of Asymmetric Synthesis and Chirotechnology of Sichuan Province and Union Laboratory of Asymmetric Synthesis Chengdu Institute of Organic Chemistry Chinese Academy of Sciences Chengdu 610041 Key Laboratory of Asymmetric Synthesis and Chirotechnology of Sichuan Province and Union Laboratory of Asymmetric Synthesis Chengdu Institute of Organic Chemistry Chinese Academy of Sciences Chengdu 610041

　　Development of new methods for the introduction of a nitrogen atom to a carbonyl group is still the most important synthetic target. Cu-catalyzed addition of organozinc reagents to α,β-unsaturated carbonyl compounds has been the subject of intensive investigation.[1] Moreover, trapping of the intermediate Zn-enolates has been achieved using nitrosobenzene. To demonstrate the feasibility of developing enantioselective variants of these tandem C-C bond formations,α,β-unsaturated substrates a～d was subjected to standard reaction conditions using Feringa's (L1*, L2*) and our own phosphoramidite ligands (L3*, L4*). In this reaction, medium to high levels of enantioselectivities were observed.……

关键词： carbonyl compounds methods for

Neuronal Activity in the Cerebellum During the Sleep-Wakefulness Transition in Mice

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Neuroscience Bulletin 2020年第8期36卷 919-931页

作者： Li-Bin Zhang Jie Zhang Meng-Jia Sun Hao Chen Jie Yan Fen-Lan Luo zhong-Xiang yao Ya-Min Wu Bo Hu Department of Physiology College of Basic Medical SciencesArmy Medical UniversityChongqing 400038China State Key Laboratory of Trauma Bums and Combined InjuryDaping Hospital/Research Institute of SurgeryArmy Medical UniversityChongqing 400042China Squadron 10 Battalion 3College of Basic Medical SciencesArmy Medical UniversityChongqing 400038China

Cerebellar malfunction can lead to sleep disturbance such as excessive daytime sleepiness,suggesting that the cerebellum may be involved in regulating sleep and/or ***,understanding the features of cerebellar regulation in sleep and wakefulness states requires a detailed characterization of neuronal activity within this *** performing multiple-unit recordings in mice,we showed that Purkinje cells(PCs)in the cerebellar cortex exhibited increased firing activity prior to the transition from sleep to ***,the increased PC activity resulted from the inputs of lowfrequency non-PC units in the cerebellar ***,the increased PC activity was accompanied by decreased activity in neurons of the deep cerebellar nuclei at the nonrapid eye-movement sleep-wakefulness *** results provide in vivo electrophysiological evidence that the cerebellum has the potential to actively regulate the sleep-wakefulness transition.

关键词： Sleep Wakefulness Multiple-unit recording Purkinje cell Deep cerebellar nuclei

Association between IgG N-glycans and Nonalcoholic Fatty Liver Disease in Han Chinese

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Biomedical and Environmental Sciences 2018年第6期31卷 454-458页

作者： ZHAO zhong yao LIU Di CAO Wei Jie SUN Ming SONG Man Shu WANG Wei WANG You Xin Beijing Key Laboratory of Clinical Epidemiology School of Public Health Capital Medical University School of Medical and Health Sciences Edith Cowan University

Nonalcoholic fatty liver disease（NAFLD） is a major public health issue worldwide. Immunoglobulin G（IgG） N-glycans are associated with risk factors for NAFLD, such as obesity and diabetes. A cross-sectional study involving 500 Han Chinese adults recruited from a community in Beijing was carried out to explore the association between IgG N-glycans and NAFLD. IgG N-glycosylation was significantly associated with NAFLD, with the disease showing a negative correlation with galactosylation（GP14, GP14n, and G2n）, positive correlation with fucosylation（FBG2n/G2n）, and positive correlation with bisecting N-acetylglucosamine（Glc NAc） [FBG2n/FG2n and FBG2n/（FG2n＋FBG2n）], after controlling age, gender, and prevalence of obesity, type 2 diabetes mellitus, hypertension, and hyperlipidemia. In other words, the present study showed a possible association between NAFLD and the loss of galactose and elevations of fucose and bisecting GlcNAc. Aberrant IgG glycosylation might therefore be a potential biomarker for the primary or secondary prevention of NAFLD.

关键词： NAFLD IgG Association between IgG N-glycans and Nonalcoholic Fatty Liver Disease in Han Chinese FBG

A morphing machining strategy for artificial bonet

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2014年第3期15卷 157-171页

作者： Wen-feng GAN Jian-zhong FU Hong-yao SHEN Zhi-wei LIN State Key Laboratory of Fluid Power Transmission and Control Department of Mechanical Engineering Zhejiang University Hangzhou 310027 China

In this work, a novel morphing machining strategy （MMS） is proposed. In the method, the workpiece is progressively carved out from the stock. Pitfalls in conventional iso-height strategy, such as sharp edges and unevenly distributed left-over materials, are overcome. Moreover, to calculate different levels in the MMS, an energy-based morphing algorithm is proposed. Finally, the proposed strategy is employed in the machining of artificial bone represented by a T-spline surface. The excellent properties of T-spline, such as expressing complex shapes with a single surface, have been well adopted to artificial bone fabri- cation. Computer simulation and the actual machining of the middle finger bone show the feasibility of the proposed strategy.

关键词： Morphing machining strategy (MMS) Energy-based morphing Tool path generation T-spline surface Artificialbone

Stereoselective Synthesis of (Z)-2-Acylamido-4-phenylcrotonates

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Chinese Chemical Letters 2000年第7期11卷 567-570页

作者： Yi Nong XIE Fan Min FU Ai Qiao MI yao zhong JIANG(Chengdu Institute of Organic Chemistry, Chinese Academy of Sciences,Chengdu 610041) Chinese Acad Sci Chengdu Inst Organ Chem Chengdu 610041 Peoples R China

Two practical methods for highly stereoselective synthesis of (Z)-2-acylamido-4-phenylcrotonates 2a similar to b have been developed. The key step in the first route was how to control the acid-catalyzed isomerization of condensation mixtures of alpha-keto ester 5 with carbomite. In the second route the key step was reduction of oxime 8, derived from alpha-keto ester 5, with iron powder in the presence of acetic anhydride.

关键词： (Z)-alpha,beta-dehydroamino acids stereoselective synthesis E -> Z isomerization Fe/Ac2O reduction of oxime

Optical evodiamine derivatives:Asymmetric synthesis and antitumor activity

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Chinese Chemical Letters 2015年第3期26卷 267-271页

作者： Zhen-Gang Li Guo-Qiang Dong Sheng-Zheng Wang Zhen-Yuan Miao Jian-zhong yao Wan-Nian Zhang Chun-Quan Sheng School of Pharmacy Second Military Medical University

Evodiamine and its derivatives have an asymmetric center at the C13 b ***,isomers of evodiamine derivatives 2 and 3 were obtained by straightforward asymmetric total *** inhibitory activities toward topoisomerases Ⅰ and Ⅱ and their cytotoxicities in cancer cell lines were *** the four isomers exhibited good to excellent antitumor potency and the（S）-isomers were generally more active than the（R）-*** binding modes of（S）-2 with topoisomerases Ⅰ and Ⅱ were also clarified by molecular docking.

关键词： isomers asymmetric antitumor clarified toward hydrogenation hexane potent relaxation dissolved

Synthesis and Antitumor Activity of 7-Substituted Derivatives of Homocamptothecin

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Chinese Chemical Letters 2006年第6期17卷 720-722页

作者： Zhen Yuan MIAO Wan Nian ZHANG Jian zhong yao Chun Quan SHENG Yun Long SONG Hui XU Min ZHANG Jing ZHANG School of Pharmacy Second Military Medical University Shanghai 200433

Thirteen homocamptothecin derivatives were synthesized and in vitro antitumor activities were evaluated by the standard MTT method. The results showed that some of the homocamptothecin derivatives had higher antitumor... 详细信息

关键词： Antitumor activity homocamptothecin synthesis.

Enhancement of the imbibition recovery by surfactants in tight oil reservoirs

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Petroleum Science 2018年第4期15卷 783-793页

作者： Zhan Meng Sheng-Lai Yang Yan Cui Zi-yao zhong Cheng-Gang Liang Lu Wang Kun Qian Quan-Zheng Ma Jun-Ru Wang Key Laboratory of Petroleum Engineering of the Ministry of Education China University of PetroleumBeijing Changqing Oilfield Company PetroChina Xinjiang Oilfield Company PetroChina

Hydraulic fracturing technology can significantly increase oil production from tight oil formations, but performance data show that production declines rapidly. In the long term, it is necessary to increase the development efficiency of block matrix, surfactant-aided imbibition is a potential way. The current work aimed to explain comprehensively how surfactants can enhance the imbibition rate. Laboratory experiments were performed to investigate the effects of wettability, interfacial tension(IFT), and relative permeability as the key parameters underlying surfactant solution imbibition. Two different types of surfactants, sodium dodecyl sulfate and polyethylene glycol octylphenol ether, at varied concentrations were tested on reservoir rocks. Experimental results showed that the oil recovery rate increased with increased wettability alteration and IFT and decreased residual oil saturation. A mechanistic simulator developed in previous studies was used to perform parametric analysis after successful laboratory-scale validation. Results were proven by parametric studies. This study,which examined the mechanism and factors influencing surfactant solution imbibition, can improve understanding of surfactant-aided imbibition and surfactant screening.

关键词： Spontaneous imbibition Tight oil reservoir Surfactants Wettability alteration Enhanced oil recovery

THEMIS statistical study on the plasma properties of high-speed flows in Earth＇s magnetotail

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Science China Earth Sciences 2016年第3期59卷 548-555页

作者： PAN Dong Xiao SUN Wei Jie SHI Quan Qi TIAN An Min yao zhong Hua FU Sui Yan ZONG Qiu Gang ZHOU Xu Zhi PU Zu Yin Shandong Provincial Key Laboratory of Optical Astronomy and Solar Terrestrial Environment School of Space Science and Physics Shandong University Weihai 264209 China State Key Laboratory of Space Weather Chinese Academy of Sciences Beijing 100190 China School of Earth and Space Sciences Peking University Beijing 100871 China Mullard Space Science Laboratory UCL Dorking RH5 6NT UK IGPP/ESS University of California Los Angeles CA 90095-1567 USA

Using Time History of Events and Macroscale Interactions during Substorms （THEMIS） observations from 2007 to 2011 tail seasons, we study the plasma properties of high speed flows （HSFs） and background plasma sheet events （BPSs） in Earth＇s magnetotail （｜YGsM｜〈13RE, ｜ZGsM｜〈5RE, -30RE〈XrsM〈-6RE）, and their correlations with solar wind parameters. Statistical results show that the closer the HSFs and BPSs are to the Earth, the hotter they become, and the temperature increase of HSFs is larger than that of BPSs. The density and temperature ratios between HSFs and BPSs are also larger when events are closer to Earth. We also find that the best correlations between the HSFs （BPSs） density and the solar wind density occur when the solar wind density is averaged 2 （3.5） hours prior to the onset of HSFs （BPSs）. The normalized densities of both HSFs and BPSs are correlated with the interplanetary magnetic field （IMF） 0 angles （ 0 = arctan（Bz √Bx^2＋y^2 ） which are averaged 3 hours before the observation time. Further analysis indicates that both HSFs and BPSs become denser during the northward IMF period.

关键词： High-speed flow Earthward evolution Interplanetary magnetic field