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FABRICATION OF SELF-ASSEMBLY DNA-C_(60) MULTILAYER FILMS

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Chinese Journal of polymer science 2002年第6期20卷 591-593页

作者： Shu-guang Yang Yong-jun Zhang Xin-hua Dai Wen-hong Tang Chun-yan Liu Wei-xiao Cao Yu-liang Li Jian Xu State Key Laboratory of polymer Physics and chemistry, Institute of chemistry, Chinese Academy of sciences,beijing 100080, china Technology Institute of Physics and chemistry Chinese Academy of sciences, beijing 100101, china college of chemistry and molecular engineering peking university beijing 100871, china Institute of chemistry Chinese Academy of Sciences State Key Laboratory of Polymer Physics and Chemistry 北京 100080 Technology Institute of Physics and chemistry Chinese Academy of Sciences 北京 100101 college of chemistry and molecular engineering Peking University 北京 100871

Electrostatic layer-by-layer self-assembly multilayer films were successfully fabricated from C-60-ethylenediamine adduct (C-60-EDA) and DNA. Under visible light irradiation, DNA is ready to be cleaved and the films a... 详细信息

关键词： self-assembly photo-induced cleavage DNA C-60

AI for organic and polymer synthesis

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science china chemistry 2024年第8期67卷 2461-2496页

作者： Xin Hong qi Yang Kuangbiao Liao Jianfeng Pei Mao Chen Fanyang Mo Hua Lu Wen-Bin Zhang Haisen zhou Jiaxiao Chen Lebin Su Shuo-qing Zhang Siyuan Liu Xu Huang Yi-zhou Sun Yuxiang Wang Zexi Zhang Zhunzhun Yu Sanzhong Luo Xue-feng Fu Shu-Li You Center of chemistry for Frontier Technologies Department of ChemistryZhejiang UniversityHangzhou 310027China Center of Basic molecular science Department of ChemistryTsinghua UniversityBeijing 100084China Guangzhou National Laboratory Guangzhou 510005China Center for Quantitative Biology Academy for Advanced Interdisciplinary StudiesPeking UniversityBeijing 100871China State Key Laboratory of molecular engineering of polymers Department of Macromolecular ScienceFudan UniversityShanghai 200433China School of Materials science and engineering Peking UniversityBeijing 100871China beijing National Laboratory for molecular sciences Center for Soft Matter Science and EngineeringKey Laboratory of Polymer Chemistry and Physics of Ministry of EducationCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China AI for science(AI4S)-Preferred Program Shenzhen Graduate SchoolPeking UniversityShenzhen 518055China State Key Laboratory of Chemical Biology Shanghai Institute of Organic ChemistryUniversity of Chinese Academy of SciencesChinese Academy of SciencesShanghai 200032China department of Chemical sciences National Natural Science Foundation of ChinaBeijing 100085China State Key Laboratory of Organometallic chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China

Recent years have witnessed the transformative impact from the integration of artificial intelligence with organic and polymer synthesis. This synergy offers innovative and intelligent solutions to a range of classic problems in synthetic chemistry. These exciting advancements include the prediction of molecular property, multi-step retrosynthetic pathway planning, elucidation of the structure-performance relationship of single-step transformation, establishment of the quantitative linkage between polymer structures and their functions, design and optimization of polymerization process, prediction of the structure and sequence of biological macromolecules, as well as automated and intelligent synthesis platforms. Chemists can now explore synthetic chemistry with unprecedented precision and efficiency, creating novel reactions, catalysts, and polymer materials under the datadriven paradigm. Despite these thrilling developments, the field of artificial intelligence(AI) synthetic chemistry is still in its infancy, facing challenges and limitations in terms of data openness, model interpretability, as well as software and hardware support. This review aims to provide an overview of the current progress, key challenges, and future development suggestions in the interdisciplinary field between AI and synthetic chemistry. It is hoped that this overview will offer readers a comprehensive understanding of this emerging field, inspiring and promoting further scientific research and development.

关键词： organic synthesis polymer synthesis machine learning prediction chemical database automated synthesis

Distinguishing malignant from normal stomach tissues and its in vivo, in situ measurement in operating process using FTIR Fiber-Optic techniques

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science china chemistry 2005年第2期48卷 167-175页

作者： XU Yizhuang1, YANG Limin1, XU Zhi3, ZHAO Ying2, LING Xiaofeng3, LI qingbo1, WANG Jiansheng4, ZHANG Nengwei3, ZHANG Yuanfu1 & WU Jinguang1 1. The State Key Laboratory of Rare Earth Materials and Applications, college of chemistry and molecular engineering, peking university, beijing 100871, china 2. Institute of chemistry, Chinese Academy of sciences, beijing 100080, china 3. department of Surgery, Third Hospital, peking university, beijing 100083, china 4. department of Oncology Surgery, the First Hospital of Xi’an Jiaotong university, Xi’an 710061, china Correspondence should be addressed to Wu Jinguang (email: wujg@***) The State Key Laboratory of Rare Earth Materials and Applications College of Chemistry and Molecular Engineering Peking University Beijing China department of Surgery Third Hospital Peking University Beijing China Institute of chemistry Chinese Academy of Sciences Beijing China department of Oncology Surgery the First Hospital of Xi’an Jiaotong University Xi’an China

Gastric tissue samples were studied using mid-IR fiber-optic attenuated total reflectance (ATR) spectroscopy. FTIR spectra of 90 tissue samples from 48 patients, including 32 normal and 58 malignant tissue samples, were chosen as examples. Malignancy was usually characterized by the absence of CH and C=O bands, a weak amide II band near 1545 cm-1, a shift of the amide I band to lower wave number, a decrease in the ～1450 cm-1 peak to less than the～1400 cm-1 peak. Subtraction spectra indicate that the amide I and amide II bands of normal and malignant tissues have larger differences in peak positions and relative intensities. The statistical analysis results confirm this conclusion. The results indicate that FTIR fiber optic techniques provide important information about cancerous tissue of the stomach, which can be used to differentiate the malignant tissue from the normal tissue. Based on the above results we successfully realize the detection of the tumor tissues of digestive tract in vivo and in situ. And the results of detection cancer near operating room and in vivo and in situ in the operating room are consistent with the conclusions for the samples stored in liquid N2, which is the basis for the clinical application.

关键词： FTIR, Fiber-Optics, stomach tissues, cancer, diagnosis.

FREE-STANDING NANOWKE ARRAYS ON CONDUCTIVE SUBSTRATE

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FREE-STANDING NANOWKE ARRAYS ON CONDUCTIVE SUBSTRATE

Asia Conference on Nanoscience and Nanotechnology Abstracts Book

作者： YONGqi LIANG, CHANGGUA ZHEN, DECHUN ZOU, DONGSHENG XU State Key Laboraroty for structural chemistry of unstable and stable specie, department of polymer science and engineering college of chemistry and molecular engineering, peking university, beijing 100871, china

As a kind of building block for constructing nano-devices by "bottom-up" method, nanowire holds huge promises for applications in optoelectronics, sensors, electronic circuits. Hierarchical assembly of nanowires in a controlled manner is a critical step towards accomplishing these goals. In particular, vertically aligned nanowire arrays on a conductive substrate are expected to have high performance in solar cells and luminescent diodes because of their well-defined channels for carriers. Template-assisted synthesis has been a common approach to prepare aligned nanowires. Because the nanopores, perpendicular to the AAO membrane surface, are uniform in diameter, and hexagonally packed, the nanowires embedded in the template form highly ordered and vertically aligned nanowire arrays. However, after the template was removed, the embedded arrays of nanowires with a high aspect-ratio normally collapse into an entangled mess due to the surface tension force exerted on the nanowires during the evaporation of the liquids. This makes template-assisted synthesis greatly limited when vertically aligned nanowire arrays are desired for devices. In mis work, we make use of the supercritical drying technique to prepare non-collapsed, vertically aligned and free-standing nanowire arrays. This new approach ensures mat the nanowires in the arrays are in direct contact with the conductive substrate and provide a continuous pathway for carrier transport Finally, we demonstrate that these vertically aligned and free-standing nanowire arrays can be feasibly used for fabricating nanowire-based inorganic-organic hybrid devices. The interface of the inorganic CdS nanowire array and the organic NPB layer shows asymmetric current voltage response, which indicates the formation of a good p-n junction.

关键词： Nanowire array Supercritical drying Hybrid device.

DEGRADABLE THERMORESPONSIVE POLYESTERS BY ATOM TRANSFER RADICAL POLYADDITION AND CLICK chemistry

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DEGRADABLE THERMORESPONSIVE POLYESTERS BY ATOM TRANSFER RADI...

第五届国际高分子化学学术讨论会

作者： Li-Jing Zhang Bo-Tao Dong Fu-Sheng Du and Zi-Chen Li beijing National Laboratory for molecular sciences(BNLMS) Key Laboratory of polymer chemistry& Physics of Ministry of Education department of polymer science&engineering college of chemistry and molecular engineering peking university beijing 100871 china.

＜正＞LCST-type thermoresponsive polymers have found a variety of applications in biomedical science ranging from smart surfaces,bio-sensing and tissue engineering to intelligent drug/gene delivery.1 However,as most of the above polymers are based on carbon-carbon backbone,the non-degradability may limit their in vivo

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1,2-lmidoyl Group Migration in Rh（ll） Carbene Reactions

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1,2-lmidoyl Group Migration in Rh（ll） Carbene Reactions

中国化学会第四届有机化学学术会议

作者： XU, feng WANG, Jian-Bo (Key Laboratory of Bioorganic chemistry and molecular engineering of Ministry of Education, department of Chemical Biology, college of chemistry, peking university, beijing 100871)

＜正＞1,2-Migration is one of the fundamental reactions in transition metal-catalyzed reaction of a-diazo carbonyl compounds. Although cyclopropanation, dimerization, and X-H （X=C, O, S, N, etc.） bond insertions are major reaction pathways, the 1,2-migration may become competitive in some cases. Among the 1,2-migration reactions, the 1,2-hydride migration is generally predominant, but 1,2-alky1, 1,2-ary1, 1,2-viny1, 1,2-acetylenyl 1,2-thio group migrations are also observed. It is also reported that 1,2-acetoxy group has a higher migratory aptitude over 1,2-hydride migration in Rh2（OAc）4-mediated reaction of a-diazo carbonyl compounds, presumably due to a favorable five-membered ring transition state 2.

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Direct Synthesis of Phosphonopeptides via Mannich-Type Four-Component Condensation

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Direct Synthesis of Phosphonopeptides via Mannich-Type Four-...

8th Chinese International Peptide Symposium

作者： Jiaxi XU, Nanyan FU, Yuanhe GAO, qihan ZHANG Key Laboratory of Bioorganic chemistry and molecular engineering of Ministry of Education, department of Chemical Biology, college of chemistry and molecular engineering, peking university, beijing 100871, china

Phosphonopeptides are important analogs of naturally occurring peptides and are widely used as enzyme inhibitors and haptens for the induction of catalytic antibodies. Phosphonopeptides were prepared traditionally from aminoalkylphosphonochloridates and amino/hydroxy esters or peptide esters. An alternative route to synthesize phosphonopeptides involves nucleophilic addition to much more reactive phoshonochloridites and followed by oxida

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The quality control mechanism for the transloction of the outer membrane proteins in the periplasm of Gram-negative bacteria

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The quality control mechanism for the transloction of the ou...

第一届全国生物物理化学会议暨生物物理化学发展战略研讨会

作者： Si Wu~1,Xi Ge~2,Zeyong Zhi~1,and Zengyi Chang~2,Xin Sheng Zhao~(1,*) 1 beijing National Laboratory for molecular sciences,State Key Laboratory for Structural chemistry of Unstable and Stable Species,and department of Chemical Biology,college of chemistry and molecular engineering,peking university,beijing,100871,china 2 The Center for Protein science,The National Laboratory of Protein engineering and Plant Genetic engineering,and college of Life science,peking university,beijing,100871,china

＜正＞The outer membrane proteins（OMPs） of the Gram negative bacteria have to be translocated through the cytoplasm,the inner membrane,and the periplasmic space before reaching their final *** highly fluctuating nature of the periplasmic space,due to the high permeability of the outer membrane,engenders such translocation process inevitably challenging and would have to rely on an efficient quality control

关键词： outer membrane protein DegP single molecule fluorescence protein quality control

Novel and Convenient Method for the Preparation of Phosphonate Peptides and Phosphonamidate Peptides

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Novel and Convenient Method for the Preparation of Phosphona...

第三届全国有机化学学术会议

作者： XU, Jia-Xi FU, Nan-Yan GAO, Yuan-He ZHNAG, qi-Han DUAN, Li-Fang (Key Laboratory of Bioorganic chemistry and molecular engineering of Ministry of Education, department of Chemical Biology, college of chemistry and molecular engineering, peking university, beijing 100871, china)

＜正＞ Phosphonate and phosphonamidate peptides are phosphorus analogues of natural peptides. They have been great used as stable mimetics of tetrahedral transition states as enzyme inhibitors and as haptens for catalytic antibody research in recent years. Although several methods are available for the preparation of phosphonate peptides and phosphonamidate peptides, all of them use phosphonic acid derivatives as starting materials. The overall yields from the synthesis of phosphonic acid derivatives to desired peptides are not satisfactory in most cases.A novel and direct method for the preparation of phosphonate mixed diesters and phosphonamidates was devel

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