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Acta Pharmaceutica Sinica B 2017年第6期7卷 638-646页

作者： Lingjie Meng Qinglan Guo Yufeng Liu Jiangong Shi State Key Laboratory of Bioactive Substance and Function of Natural Medicines Institute of Materia MedicaChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100050China

Three pairs of glycosidic 8,4′-oxyneolignane diastereoisomers, named isatioxyneolignosides A-F(1–6), were isolated from an aqueous extract of Isatis indigotica roots. Their structures and absolute configurations were elucidated by comprehensive spectroscopic data analysis and enzyme hydrolysis. The validity of Δδ_(C8-C7) values to distinguish threo and erythro aryl glycerol units and Cotton effects at 235±5 nm to determine absolute configurations at C-8 in 1–6 and their aglycones(1a–6a) are discussed.

关键词： Cruciferae Isatis indigotica Isatioxyneolignosides A-F 8,4′-Oxyneolignane Threolerythro Isomers ΔδC8-C7 value absolute configuration Cotton effect

Crystal and Molecular Structure of N-(1-Ethoxycarbonyl- ethyl)1-Ethoxycarbonylmethyl-3-ethyl-1,2,3,4- tetrahydro-4-oxo-1,3,2-benzodiazaphosphorin- 2-carboxamide 2-Oxide

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Chinese Journal of Structural Chemistry 2001年第5期20卷 349-353页

作者：黄君珉陈茹玉等 Institute of Elemento-Organic Chemistry， Nankai University

The crystal structure of the title compound N-(1-ethoxycarbonyl-ethyl) 1-ethoxycarbonylmethy-3-ethyl-1,2,3,4-tetrahydro-4-oxo-1,3,2-benzodiazaphosphorin-2-carbox amide 2-oxide, (C19H_26N3O7P, Mr = 439.41), was determined by single crystal X-ray diffraction at 299(1) K. It crystallizes in the triclinic system, space group P (No.2) with a = 8.955(2), b = 11.863(2), c = 12.309(2) ?, ( = 62.67(3),β= 68.10(3), ( = 78.07(3)(, V = 1077(1) ?3, Z = 2, Dx =1.355 g·cm－3, ( = 0.71073 ?, ( = 0.1657 mm－1 and F(000) = 464. The structure was solved by direct methods. The final R factor is 0.071 and Rw is 0.076 for 2176 observed reflections with I ≥3((I). The results from X-ray crystallography analysis of the isomer with 31P NMR spectra exhibited as ( 4.09 show that the absolute configuration of the chiral phosphorus atom at P(1) was proved to be S-form, with reference to the known configuration of R-alanine moiety.

关键词： crystal structure absolute configuration benzodiazaphosphorine (-amino acid (-ketophosphondiamidate

Recent progress in chiral zeolites: Structure, synthesis,characterization and applications

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Chinese Chemical Letters 2024年第12期35卷 33-42页

作者： Teng-Yu Huang Junliang Sun De-Xian Wang Qi-Qiang Wang Beijing National Laboratory for Molecular Sciences CAS Key Laboratory of Molecular Recognition and FunctionInstitute of ChemistryChinese Academy of SciencesBeijing 100190China College of Chemistry and Molecular Engineering Beijing National Laboratory for Molecular SciencesPeking UniversityBeijing 100871China University of Chinese Academy of Sciences Beijing 100049China

Zeolites are crystalline porous materials that are used in the chemical industry for adsorption, separation and catalytic reactions. Chiral zeolites have shown promise in enantioselective adsorption and catalytic organic reactions, attracting significant research interest. Recent advances have been made in the rational design, computational prediction and hydrothermal synthesis of using chiral organic structure-directing agents. Additionally, newly developed electron microscopic techniques have been utilized to analyze the structure and determine absolute configuration. The following review aims to provide an overview of the development history of chiral zeolites, examine several prominent chiral zeolite structures discovered so far, discuss the recent progress in characterization methods and explore their potential applications.

关键词： Chiral zeolite Chirality Organic structure-directing agent absolute configuration Electron microscopy Enantioselective catalysis

Synthesis of the optically pure 5,5"-dihydroxy-7,7"-dimethoxy-8,8"-biflavone and its derivatives

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Chinese Journal of Chemistry 1997年第5期15卷 464-471页

作者： Zhang, FJ Lin, GQ Chinese Acad Sci Shanghai Inst Organ Chem Shanghai 200032 Peoples R China

(+/-)-5,5 '-Dihydroxy-7,7 '-dimethoxy-8,8 '-biflavone ((+/-)-1) was resolved into its optically pure forms via the formation and recrystallization of its (2R)- and (2S)-1-(4-toluenesulfonyl)prolylate, and the methylated derivatives of (+)- and (-)-1 were also prepared. The absolute configurations of all these 8,8 '-biflavones have been confirmed by their CD spectra.

关键词： 8,8 ''-biflavones synthesis optical resolution absolute configuration CD spectra

A New Synthetic Route to Diastereomerically Pure Cyclopropane-Phosphorus Derivatives Utilizing the Chiron 5-L-Men-thyloxy-3-bromo-2(5H)-furanone and Racemic Dialkyl α-Hydroxyalkanephosphonate

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Chinese Journal of Chemistry 2002年第11期20卷 1340-1346,1131页

作者：范雪娥傅玉琴王建革杜巧云陈庆华 Department of Chemistry Luoyang Teacher's College Luoyang Henan 471022 China Email: Qing-Hua Chen (qinghuac@***)

A new chemical transformation for the construction of diversely functionalized cyclopropane-phosphorus derivatives utilizing chiron 4 and racemic diethyl α-hydroxylbenzylphosphonate as the key precursors is described. The diastereomeric pure phosphorus-containing derivatives 5a, 5′a, 5b and 5′b were obtained respectively, in good yields with d. e. 98% via asymmetric tandem double Michael addition/internal nucleophilic substitution of the corresponding compounds and further through the separation of the diastereomeric mixture by column chromatography. The diversely functionalized phosphorus derivatives are identified on the basis of their elemental analysis and spectroscopic data, such as K, 1H NMR, 13C NMR and MS. The absolute configuration of the interesting cyclopropane-phosphorus compound 5a was established by X-ray crystallography. Thus, these results provide a valuable strategy for synthesizing some biologically active molecules.

关键词： diastereomerically pure cyclopropane-phosphorus derivatives tandem asymmetric reaction racemic diethyl α-hydroxylbenzylphosphonates biological activity absolute configuration X-ray crystallography

Synthesis and Crystal Structure of tert-Butyl(((2R,3R,6R)-3-hydroxy-6-(nitromethyl)-3,6-dihydro-2H-pyran-2-yl)methyl)carbonate

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Chinese Journal of Structural Chemistry 2021年第9期40卷 1205-1212,1110页

作者： FENG Yong-Kui SU Hua-Lan MUKULA OTUKOL Billy Joel ZHANG Xue-Qing YAO Hui HUANG Nian-Yu Hubei Key Laboratory of Natural Products Research and Development Key Laboratory of Functional Yeast(China National Light Industry)College of Biological and Pharmaceutical SciencesChina Three Gorges UniversityTichangHubei 443002China

In this paper,aβ-C-pyranogalactoside(Ⅸ)was synthesized from D-galactose through a nine-step reaction with a total yield of 32%under the palladium catalyst,and its structure was characterized by nuclear magnetic resonance(NMR)and high-resolution electrospray ionization mass spectrometry(HR-ESI-MS).The absolute configuration of this pyranogalactoside was confirmed with a Flack parameter of–0.01(6)by X-ray crystallography using a Cu radiation ***(Ⅸ),C_(12)H_(19)NO_(7),crystal data:monoclinic system,space group P2_(1)2_(1)2_(1),a=8.53480(10),b=9.4207(2),c=18.1308(3)A,V=1457.79(4)A^(3),Z=4,F(000)=616,Dc=1.318 g/cm^(3),μ=0.931 mm^(-1),R=0.0294 and wR=0.0752 for 2875 independent reflections(R_(int)=0.0163)and 2857 observed ones(I>2σ(I)).

关键词： X-ray diffraction crystal structure absolute configuration β-C-pyranogalactoside α-glucosidase inhibitory activity

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A pair of cyclopeptide epimers from the seeds of Celosia argentea

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Chinese Journal of Natural Medicines 2018年第1期16卷 63-69页

作者： LIU Feng-Jie ZHU Zhi-Hua JIANG Yan LI Hui-Jun State Key Laboratory of Natural Medicines China Pharmaceutical University Nanjing 210009 China Anhui Medical College Hefei 230601 China School of Chemical Engineering Nanjing Forestry University Nanjing 210037 China

Two cyclopeptides, celogentin L(1) and its epimer lyciumin A(2) were firstly isolated from Celosia argentea L.. The planar structures of the two compounds were fully determined by spectroscopic data, including 1 D-, 2 D-NMR, and HR-ESI/MS. The absolute configurations of amino acid components were assigned via chiral-phase HPLC analyses after acid hydrolysis. Furthermore, the configuration of C-N linkage at the glycine Cα was elucidated by extensive analyses of 2 D-NMR and comparison of the experimental and calculated electronic circular dichroism(ECD) spectra. Cytotoxicity of the two compounds against human alveolar epithelial A549, hepatocellular carcinoma Hep G2, and cervical cancer Hela cell lines was assayed. Although both of them were inactive in these cells, the present findings add new facets for the chemistry of Celosia argentea.

关键词： Celosia argentea Cyclopeptides Lyciumin A Celogentin L absolute configuration

Chromopeptide A, a highly cytotoxic depsipeptide from the marine sediment-derived bacterium Chromobacterium sp. HS-13-94

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Acta Pharmaceutica Sinica B 2015年第1期5卷 62-66页

作者： Zhenfang Zhou Xin Wang Hui Zhang Jingya Sun Linghui Zheng Hongchun Liu Jidong Wang Aijun Shen Meiyu Geng Yuewei Guo State Key Laboratory of Drug Research Shanghai Institute of Materia Medica Chinese Academy of Sciences Zhejiang Hisun Pharmaceutical Co. Ltd.

A bicyclic depsipeptide, chromopeptide A(1), was isolated from a deep-sea-derived bacterium Chromobacterium sp. HS-13-94. Its structure was determined by extensive spectroscopic analysis and by comparison with a related known compound. The absolute configuration of chromopeptide A was established by X-ray diffraction analysis employing graphite monochromated Mo K_α radiation(λ ? 0.71073 ?) with small Flack parameter 0.03. Chromopeptide A suppressed the proliferation of HL-60, K-562, and Ramos cells with average IC_(50) values of 7.7, 7.0, and 16.5 nmol/L, respectively.

关键词： Chromopeptide A Bacterium Depsipeptide absolute configuration Marine-derived Sediments Cytotoxicity Chromobacterium sp.

ECD spectrometric methods for detecting the enantioselective enzymatic hydrolysis of racemic 3-acetoxy-4-phenyl-β-lactam

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Chinese Chemical Letters 2012年第10期23卷 1197-1200页

作者： Xiang Zhang Li Li Yi Kang Si Da Li Yin Beijing Key Laboratory of Active Substances Discovery and Druggability Evaluation Institute of Materia MedicaChinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100050China

（-）-（3R, 4S）-3-Acetoxy-4-phenylazetidin-2-one （（-）-1） was the key intermediate for preparing optical C-13 side-chain moiety in partial synthesis of docetaxel and paclitaxel. It can be successfully prepared via enantioselective hydrolysis of racemic esters （（-4-）-1） catalyzed by bacterial lipases, but the current reaction evaluation method is tedious and inconvenient. Electronic circular dichroism （ECD） has been widely applied in the stereochemical study of chiral compounds. In this paper, a rapid ECD spectroscopic method has been proposed and established to detect the transformation directly. The absolute configurations of lipase-catalyzed hydrolysis products have also been confirmed by quantum-chemical calculation using time-dependent density functional theory （TDDFT） methodology.

关键词： ECD spectroscopy Evaluation method absolute configuration Time-dependent density functional theory

Rearranged diterpenoids from the seeds of Caesalpinia sappan

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Chinese Chemical Letters 2016年第12期27卷 1751-1754页

作者： Fang Xiao Chun-Ping Tang Chang-Qiang Ke Sheng Yao Yang Ye State Key Laboratory of Drug Research & Natural Products Chemistry Department Shanghai Institute of Materia Medica Chinese Academy of Sciences Shanghai 201203 China University of Chinese Academy of Sciences Beijing 100049 China School of Life Science and Technology Shanghai Tech University Shanghai 201210 China

Two new rearranged diterpenoids, tomocinol C （1） and spirocaesalmin C （2） were isolated from the seeds of Caesalpinia sappan. Their structures were elucidated based on comprehensive analysis of spectroscopic data,... 详细信息

关键词： Diterpenoid Tomocinol C Spirocaesalmin C Caesalpinia sappan absolute configuration X-ray crystallography