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Multicomponent Domino [4＋1＋1] Carbocyclization Providing an Efficient and Regioselective Strategy to Fluoren-9-ones

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Chinese Journal of Chemistry 2013年第6期31卷 737-744页

作者： Ying li haiwei Xu liping Fu Qingqing Shi Bo Jiang Shujiang Tu School of Chemistry and Chemical Engineering Laboratory of Green Synthetic Chemistry for Functional Materials Jiangsu Normal University Xuzhou Jiangsu 221116 China

Concise and efficient three-component domino [4＋ 1 ＋ 1] carbocyclization to highly substituted fluoren-9-one derivatives promoted by K2CO3 has been developed under microwave irradiation conditions. The direct bis-cyanation and aryl amination residing in fluoren-9-one framework were achieved in a one-pot operation. The reaction proceeds at fast rates and can be finished within 30 min, which makes workup convenient to give good to excellent chemical yields.

关键词： fluoren-9-one synthesis multicomponent reactions carbocyclization regioselectivity microwaveheating

Atomic scale electronic structure of the ferromagnetic semiconductor Cr2Ge2Te6

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Science Bulletin 2018年第13期63卷 825-830页

作者： Zhenqi Hao haiwei li Shunhong Zhang Xintong li Gaoting lin Xuan Luo Yuping Sun Zheng liu Yayu Wang State Key Laboratory of Low Dimensional Quantum Physics Department of PhysicsTsinghua UniversityBeijing 100084China Institute for Advanced Study Tsinghua UniversityBeijing 100084China Key Laboratory of Materials Physics Institute of Solid State PhysicsChinese Academy of SciencesHefei 230031China University of Sdence and Technology of China Hefei 230026China e High Magnetic Field LaboratoryChinese Academy of SciencesHefei 230031China High Magnetic Field Laboratory Chinese Academy of SdencesHefei 230031China Collaborative Innovation Centre of Advanced Microstructures Nanjing UniversityNanjing 210093Chinag Collaborative Innovation Center of Quantum Matter Beijing 100084China

Cr_2Ge_2Te_6is an intrinsic ferromagnetic semiconductor with van der Waals type layered structure,thus represents a promising material for novel electronic and spintronic *** we combine scanning tunneling microscopy and first-principles calculations to investigate the electronic structure of Cr_2Ge_2Te_*** spectroscopy reveals a surprising large energy level shift and change of energy gap size across the ferromagnetic to paramagnetic phase transition,as well as a peculiar double-peak electronic state on the Cr-site *** features can be quantitatively explained by density functional theory calculations,which uncover a close relationship between the electronic structure and magnetic *** findings shed important new lights on the microscopic electronic structure and origin of magnetic order in Cr_2Ge_2Te_6.

关键词： Ferromagnetic semiconductor Electronic structure Scanning tunneling microscopy Density functional theory

Biosynthesis of fungus-based oral selenium microcarriers for radioprotection and immuno-homeostasis shaping against radiation-induced heart disease

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Bioactive Materials 2024年第7期37卷 393-406页

作者： Chang liu Weiyi Wang Haoqiang Lai Yikang Chen Lvyi li haiwei li Meixiao Zhan Tianfeng Chen Wenqiang Cao Xiaoling li Zhuhai People’s Hospital(Zhuhai Clinical Medical College of Jinan University) Zhuhai519000PR China Zhuhai Jinan Selenium Source Nanotechnology Co. LtdJinan UniversityZhuhai 519000China Department of Chemistry Institute of Food Safety and NutritionJinan UniversityGuangzhou 510632China Guangdong Jinan Established Selenium Source Nano Technology Research Institute Co. Ltd.Guangzhou 510535China

Radiation-induced heart disease(RIHD),characterized by severe oxidative stress and immune dysregulation,is a serious condition affecting cancer patients undergoing thoracic ***,clinical interventions for RIHD are ***(Se)is a trace element with excellent antioxidant and immune-modulatory ***,its application in heart radioprotection remains ***,we developed a novel bioactive Cordyceps militaris-based Se oral delivery system(Se@CM),which demonstrated superior radioprotection effects in vitro against X-ray-induced damage in H9C2 cells through suppressing excessive ROS generation,compared to the radioprotectant ***,Se@CM exhibited exceptional cardioprotective effects in vivo against X-ray irradiation,reducing cardiac dysfunction and myocardial fibrosis by balancing the redox equilibrium and modulating the expression of Mn-SOD and ***,Se@CM maintained immuno-homeostasis,as evidenced by the upregulated population of T cells and M2 macrophages through modulation of selenoprotein expression after ***,these results highlight the remarkable antioxidant and immunity modulation properties of Se@CM and shed light on its promising application for cardiac protection against IR-induced *** research provides valuable insights into developing effective strategies for preventing and managing RIHD.

关键词： Radiation-induced heart disease Antioxidant Selenium Selenoprotein Heart protection

Temperature Dependence of the Electronic Structure of Ca_(3)Cu_(2)O_(4)Cl_(2) Mott Insulator

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Chinese Physics Letters 2022年第1期39卷 36-39页

作者： haiwei li Shusen Ye Jianfa Zhao Changqing Jin Yayu Wang State Key Laboratory of Low-Dimensional Quantum Physics Department of PhysicsTsinghua UniversityBeijing 100084China Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China Songshan Lake Materials Laboratory Dongguan 523808China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China Frontier Science Center for Quantum Information Beijing 100084China

We use scanning tunneling microscopy to study the temperature evolution of electronic structure in Ca_(3)Cu_(2)O_(4)Cl_(2) parent Mott insulator of cuprates. It is found that the upper Hubbard band moves towards the Fermi energy with increasing temperature, while the charge transfer band remains basically unchanged. This leads to a reduction of the charge transfer gap size at high temperatures, and the rate of reduction is much faster than that of conventional semiconductors. Across the Neel temperature for antiferromagnetic order, there is no sudden change in the electronic structure. These results shed new light on the theoretical models about the parent Mott insulator of cuprates.

关键词： unchanged faster insulator

Machine learning identification of impurities in the STM images

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Chinese Physics B 2020年第11期29卷 81-85页

作者： Ce Wang haiwei li Zhenqi Hao Xintong li Changwei Zou Peng Cai Yayu Wang Yi-Zhuang You Hui Zhai Institute for Advanced Study Tsinghua UniversityBeijing 100084China State Key Laboratory of Low Dimensional Quantum Physics Department of PhysicsTsinghua UniversityBeijing 100084China Department of Physics and Beijing Key Laboratory of Opto-electronic Functional Materials and Micro-nano Devices Renmin University of ChinaBeijing 100872China Frontier Science Center for Quantum Information Beijing 100084China Department of Physics University of CaliforniaSan DiegoCalifornia 92093USA

We train a neural network to identify impurities in the experimental images obtained by the scanning tunneling microscope(STM)*** neural network is first trained with a large number of simulated data and then the trained neural network is applied to identify a set of experimental images taken at different *** use the convolutional neural network to extract features from the images and also implement the attention mechanism to capture the correlations between images taken at different *** note that the simulated data can capture the universal Friedel oscillation but cannot properly describe the non-universal physics short-range physics nearby an impurity,as well as noises in the experimental *** we emphasize that the key of this approach is to properly deal with these differences between simulated data and experimental *** we show that even by including uncorrelated white noises in the simulated data,the performance of the neural network on experimental data can be significantly *** prevent the neural network from learning unphysical short-range physics,we also develop another method to evaluate the confidence of the neural network prediction on experimental data and to add this confidence measure into the loss *** show that adding such an extra loss function can also improve the performance on experimental *** research can inspire future similar applications of machine learning on experimental data analysis.

关键词： scanning tunneling microscope neural network attention data regularization

Facile preparation and characterization of novel oleanane-type triterpene functionalized β-cyclodextrin conjugates

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Chinese Chemical Letters 2019年第3期30卷 690-693页

作者： Pingxuan Jiao Shouxin Wang Shuobin liang Man li Qianqian Gao Dezhong Ji Yingying Chen haiwei li Fuxiang Ran Yongmin Zhang lihe Zhang Demin Zhou Sulong Xiao State Key Laboratory of Natural and Biomimetic Drugs School of Pharmaceutical Sciences Peking University School of Pharmacy Jining Medical University Sorbonne Universite Institut Parisien de Chimie Moleculaire CNRS UMR 8232 State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of Botany Chinese Academy of Sciences

Oleanolic acid(OA) and echinocystic acid(EA), two naturally occurring pentacyclic oleanane triterpenes,are gaining increasing attention due to their promising pharmacological activities. Conjugation with amphiphilic α(β)-cyclodextrin(CD) via "click chemistry" can improve their solubility and anti-HCV entry potency. In the present work,four water-soluble β-CD-pentacyclic triterpene conjugates were designed and synthesized, in which OA and EA was coupled to one of the primary hydroxyl groups of β-CD via ester and amide bonds. The structures of the conjugates were unambiguously determined by ~1H NMR, ^(13)C NMR and HRMS or MALDI-TOF-MS. All the conjugates showed lower hydrophobicity(AlogP) than their parent compounds and no significant cytotoxicity was found to HL-60, A549, Hela and Bel-7402 cells at concentrations up to 10 μmol/L. Further anti-HCV entry activity and mechanism studies are under way in our laboratory.

关键词： β-Cyclodextrin DIBAL-H Oleanolic acid Echinocystic acid Synthesis

Imaging the atomic-scale electronic states induced by a pair of hole dopants in Ca_(2)CuO_(2)Cl_(2) Mott insulator

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Science Bulletin 2021年第14期66卷 1395-1400,M0003页

作者： haiwei li Shusen Ye Jianfa Zhao Changqing Jin Yayu Wang State Key Laboratory of Low Dimensional Quantum Physics Department of PhysicsTsinghua UniversityBeijing 100084China Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China Songshan Lake Materials Laboratory Dongguan 523808China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China Frontier Science Center for Quantum Information Beijing 100084China

We use scanning tunneling microscopy to visualize the atomic-scale electronic states induced by a pair of hole dopants in Ca_(2)CuO_(2)Cl_(2)parent Mott insulator of *** find that when the two dopants approach each other,the transfer of spectral weight from high energy Hubbard band to low energy ingap state creates a broad peak and nearly V-shaped gap around the Fermi *** peak position shows a sudden drop at distance around 4 a_(0)and then remains almost *** in-gap states exhibit peculiar spatial distributions depending on the configuration of the two dopants relative to the underlying Cu *** results shed important new lights on the evolution of low energy electronic states when a few holes are doped into parent cuprates.

关键词： Cuprates Mott insulator Charge transfer gap Impurity state Scanning tunneling microscopy

Development of a small-molecule degrader of hemagglutinin to reduce the replication of influenza virus.

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Development of a small-molecule degrader of hemagglutinin to...

第十一届全国化学生物学学术会议

作者： haiwei li Jiaqi Sun Xinchen Wang Sulong Xiao Demin Zhou State Key Laboratory of Natural and Biomimetic Drugs School of Pharmaceutical SciencesPeking University

PROteolysis-TArgeting Chimeras（PROTACs） are bivalent small molecules that recruit an E3 ligase to the protein of interest and then induce its ubiquitination and degradation by proteasome.[1] Previous works mainly focus on the degradation of endogenous proteins such as nuclear receptors, protein kinases, transcriptional regulation proteins and so on.[2] In this work, we report the success in antivirus application by degrading influenza hemagglutinin proteins through introducing the E3 ligase CRBN or VHL-binding ligands to hemagglutinin inhibitor Oleanolic acid（OA）. CRBN ligand-based compounds show limited degradation effect（＜50%） with hook tendency while the compounds with VHL ligand show more prominent degradation ability with higher concentration. Moreover, V3 with the longest linker exerted the best degradation capacity（80 %） in protein and virus level. Our data reveal that PROTAC could be used in degrading viral proteins to develop new kinds of antivirus drugs.

关键词： PROTAC Triterpene Hemagglutinin anti-influenza

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仿猿双臂手机器人连续摆荡移动优化与实验

哈尔滨工业大学学报 2019年第7期51卷 33-41页

作者：吴伟国李海伟哈尔滨工业大学机电工程学院

针对仿生悬摆机器人在连续移动过程中不能可靠抓握目标杆的问题,提出调整双手抓杆构形使势能最大、摆荡运动关节轨迹优化、大阻尼切换与大阻尼抓杆的分阶段控制策略.给出分阶段控制下各主动驱动关节PID控制器的期望目标关节轨迹计算公... 详细信息

针对仿生悬摆机器人在连续移动过程中不能可靠抓握目标杆的问题,提出调整双手抓杆构形使势能最大、摆荡运动关节轨迹优化、大阻尼切换与大阻尼抓杆的分阶段控制策略.给出分阶段控制下各主动驱动关节PID控制器的期望目标关节轨迹计算公式和各阶段光滑运动的切换条件,利用ADAMS与MATLAB/Simulink软件进行仿猿双臂手机器人连续抓握不同间距目标杆的移动控制仿真.用自行研制的BARDAH-I型仿猿双臂手机器人分别进行了起始杆与中间杆间距1m,中间杆与目标杆间距依次为0.5、0.6、0.7、0.8m总计12次实验,实验成功率100%.实验结果证明所提出的控制方法能够有效提高仿猿双臂手机器人连续移动的成功率.

关键词：仿猿双臂手机器人大阻尼退转反馈欠驱动控制连续抓杆移动自运动优化