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Chirality pairing recognition,a unique reaction forming spiral alkaloids from amino acids stereoselectively in one-pot

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Natural Products and Bioprospecting 2012年第2期2卷 53-58页

作者： Bing BAI Da-Shan LI Sheng-zhuo huaNG jie REN hua-jie zhu State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of BotanyChinese Academy of SciencesKunming 650201China Key Laboratory of Medicinal Chemistry and Molecular Diagnosis of Ministry of Education College of Life ScienceHebei UniversityBaoding071002China Graduate University of Chinese Academy of Sciences Beijing 100049China

A novel chirality pairing recognition was found between D-and L-amino acid *** spiral alkaloids formed in the recognition *** mechanism was proposed for the stereoselective and chemoselective reactions.

关键词： chirality pairing recognition reaction spiral alkaloid amino acid derivatives

Marine-derived fungi as a source of bioactive indole alkaloids with diversifed structures

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Marine Life Science & Technology 2021年第1期3卷 44-61页

作者： Zhi-Hui Meng Tian-Tian Sun Guo-Zheng Zhao Yu-Fei Yue Qing-hua Chang hua-jie zhu Fei Cao College of Pharmaceutical Sciences Institute of Life Science and Green DevelopmentHebei UniversityBaoding 071002China

Marine-derived fungi are well known as rich sources of bioactive natural *** evidences indicated that indole alkaloids,isolated from a variety of marine-derived fungi,have attracted considerable attention for their diverse,challenging structural complexity and promising bioactivities,and therefore,indole alkaloids have potential to be pharmaceutical lead *** compilation of the relevant *** this review,we demonstrated a comprehensive overview of 431 new indole alkaloids from 21 genera of marine-derived fungi with an emphasis on their structures and bioactivities,covering literatures published during 1982–2019.

关键词： Indole alkaloid Marine-derived fungus Chemical diversity Bioactivity

Chiral Ligands from Abrine.4. Heterocycle-Containing 1,2,3,4-Tetrahydro-β-Carboline Methyl Ester Used for Catalysis of Enantioselective Addition of Diethylzinc to Benzaldehyde

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Chinese Chemical Letters 1998年第6期9卷 527-528页

作者： Bi Tao ZHAO hua jie zhu Xing HONG Jun ZHOU Xiao Jiang HAO(KunAnng Institute of Botany, Chinese Academy of Sciences, Heilongtan, Kunming 650204) Chinese Acad Sci Kunming Inst Bot Kunming 650204 Peoples R China

Four 1, 2,3,4-tetrahydro - β - c arboline amino acid esters with a heterocycle at the C- 1position were used as chiral ligands in the enantioselective addition reactions. The differentpositions of the heteroatoms gav... 详细信息

关键词： Enantioselective addition diethylzinc 1,2,3,4-tetrahydro-β-carboline ester

Investigation of Improved Approaches to Bayes Risk Decoding

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Journal of Shanghai Jiaotong university(Science) 2011年第5期16卷 524-529页

作者：徐海华朱杰 Department of Electronic Engineering Shanghai Jiaotong University

Bayes risk (BR) decoding methods have been widely investigated in the speech recognition area due to its flexibility and complexity compared with the maximum a posteriori (MAP) method regarding to minimum word error (MWE) optimization. This paper investigates two improved approaches to the BR decoding, aiming at minimizing word error. The novelty of the proposed methods is shown in the explicit optimization of the objective function, the value of which is calculated by an improved forward algorithm on the lattice. However, the result of the first method is obtained by an expectation maximization (EM) like iteration, while the result of the second one is achieved by traversing the confusion network (CN), both of which lead to an optimized objective function value with distinct approaches. Experimental results indicate that the proposed methods result in an error reduction for lattice rescoring, compared with the traditional CN method for lattice rescoring.

关键词： Bayes risk (BR) confusion network (CN) speech recognition lattice rescoring

Absolute configurations of natural products from marine-derived fungi by vibrational circular dichroism

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Absolute configurations of natural products from marine-deri...

Seven New Drimane-Type Sesquiterpenoids from Cultures of Fungus Phellinus tuberculosus

中国菌物学会2018年学术年会

作者： Fei Cao hua-jie zhu College of Pharmaceutical Sciences Hebei University

Vibrational circular dichroism（VCD） spectroscopy, which has been published as a new "standard method" in the U. S. Pharmacopeia, has proven to be one of the most important chiroptical methods for the assignment of absolute configurations in natural products [1]. Especially, VCD presents many advantages compared to the other methods, since it requires no crystallization or further chemical modification of the molecule and can readily be done in solution [2]. In our continuing efforts to explore bioactive natural procucts from marine-derived fungi collected from the Bohai Sea. The absolute configurations of some compounds were difficult to be assigned due to the high conformational flexibility of the chains. To address these problem, the experimental VCD of them were compared with the corresponding DFT calculations for different diastereomers[3-5]. This study suggestted the VCD method has become a robust and reliable alternative for the stereochemical characterization of natural products.

关键词： Vibrational circular dichroism natural product marine-derived fungus

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Natural Products and Bioprospecting 2014年第1期4卷 21-25页

作者： Jiang-Bo He Tao Feng Shen Zhang Ze-Jun Dong Zheng-Hui Li hua-jie zhu Ji-Kai Liu State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of BotanyChinese Academy of SciencesKunming 650201People’s Republic of China University of Chinese Academy of Sciences Beijing 100049People’s Republic of China

Seven new drimane-type sesquiterpennoids,phellinuins A-G(1-7),together with one known compound 3b,11,12-trihydroxydrimene(8)were isolated from the cultures of mushroom Phellinus *** structures were elucidated on the b... 详细信息

关键词： Phellinus tuberculosus Drimane-type sesquiterpennoids Phellinuins A–G

Fuzzy C-Means Clustering Based Phonetic Tied-Mixture HMM in Speech Recognition

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Journal of Shanghai Jiaotong university(Science) 2005年第1期10卷 16-20页

作者：徐向华朱杰郭强 Dept.of Electronic Eng. Shanghai Jiaotong Univ.Shanghai 200030China

A fuzzy clustering analysis based phonetic tied-mixture HMM(FPTM) was presented to decrease parameter size and improve robustness of parameter training. FPTM was synthesized from state-tied HMMs by a modified fuzzy C-means clustering algorithm. Each Gaussian codebook of FPTM was built from Gaussian components within the same root node in phonetic decision tree. The experimental results on large vocabulary Mandarin speech recognition show that compared with conventional phonetic tied-mixture HMM and state-tied HMM with approximately the same number of Gaussian mixtures, FPTM achieves word error rate reductions by 4.84% and 13.02% respectively. Combining the two schemes of mixing weights pruning and Gaussian centers fuzzy merging, a significantly parameter size reduction was achieved with little impact on recognition accuracy.

关键词： speech recognition hidden Markov model (HMM) fuzzy C-means (FCM) phonetic decision tree

Effect of Different High CO_2 Concentrations on the Development of 2-cell Mouse Embryos in vitro

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Journal of Reproduction and Contraception 2003年第3期14卷 141-146页

作者： Li-hua LU, Wei-jie zhu Center for Reproductive Immunology Research, Jinan University, Guangzhou 510632, China Center for Reproductive Immunology Research Jinan University Guangzhou 510632 China

Objective To investigate effects of different high CO_2 concentrations on the development of 2-cell mouse embryos in vitro Methods At levels of 5% CO_2 (control group), 5.7% CO_2, 6.0% CO_2 and 15% CO_2, embryos were incubated in drops with CZB medium, respectively, and the drops were covered by paraffin oil which was treated with three-distilled water. In addition, at the level of 15% CO_2, there were another two groups, in which paraffin oil was treated with phosphate-buffered saline (PBS) solution or the drops were uncovered. The development of embryos in all stages was noted. Results The developmental rates of blastocysts in five experimental groups were significantly lower than that of the control group (P0.05). At the level of 15% CO_2, 15% embryos developed in the 4-cell stage with irregular blastomere and degenerated quickly in the group which paraffin oil was treated with distilled water; 2.2% embryos developed in the 4-cell stage in the group which paraffin oil was treated with PBS and the rest stagnated in the 2-cell stage. Conclusions High CO_2 concentrations had toxic effect on the in vitro development of 2-cell mouse embryos, and was responsible for the inhibition of the embryos. It is important for the development of embryos in vitro to detect strictly CO_2 concentration.

关键词： CO_2 concentration in vitro culture quality control mouse embryo

Cyano migration-mediated radical-polar crossover cyclopropanation

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Science China Chemistry 2025年第01期 241-248页

作者： Ziqiang Wang Yasu Chen jie Li Chen zhu Key Laboratory of Organic Synthesis of Jiangsu Province College of Chemistry Chemical Engineering and Materials ScienceSoochow University Frontiers Science Center for Transformative Molecules Zhangjiang Institute for Advanced Study and Shanghai Key Laboratory for Molecular Engineering of Chiral Drugs Shanghai Jiao Tong University

We report a novel cyano migration-mediated radical-polar crossover process, whereby both the sulfonylcyanation of aliphatic alkenes and the formation of cyclopropanes are concurrently achieved. This transformation yields a diverse array of multisubstituted cyclopropanes under mild photocatalytic conditions. Mechanistic studies elucidate that the reaction proceeds via intramolecular nucleophilic substitution, leading to the formation of the cyclopropane derivatives.

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