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A practical synthesis of (-)fosfomycin from its enantiomer

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Chinese Chemical Letters 2008年第11期19卷 1297-1300页

作者： Meng Zhang Zheng Yu Ji Jun Li Da Li Yin Beijing Collab Pharma Co. Ltd. Beijing 102600 China Institute of Materia Medica Peking Union Medical College Beijing 100050 China

（＋）-cis-（1S, 2R）-Epoxypropylphosphonic acid, the enantiomer of fosfomycin, which is the industrial side-product in the preparation of the antibiotic fosfomycin, was converted into （-）fosfomycin by a seven-step procedure. The esterification of the dihydroxyphosphonic intermediate was the key step. The title compound was obtained in good yield and its optical purity was up to the medicine quality standard of Chinese Pharmacopoeia.

关键词： Fosfomycin enantiomer Phosphonate

THERMODYNAMIC ANALYSIS OF THE enantiomer RESOLUTION OF TFA-Ala-OMe, TFA-Ala-Ala-OMe, AND TFA-Ala-Ala-Ala-OMe BY GAS CHROMATOGRAPHY ON CHIRASIL-VAL

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Science China Chemistry 1991年第7期34卷 769-776页

作者：林炳承 E.BAYER V.MUSCHALEK B.KOPPENHOEFER Dalian Institute of Chemical Physics Academia SinicaDalian 116012 PRC Instisut

TFA-Ala-OMe, TFA-Ala-Ala-OMe, and TFA-Ala-Ala-Ala-OMe can be separated into 1, 2, and 4 enantiomeric pairs, respectively, by GC on the chiral stationary phase Chirasil-Val. The selectivity of the chiral stationary phase for the different stereoisomers is controlled by both interaction enthalpy and interaction entropy. The interaction enthalpy is approximately proportional to the number of Ala units. Although the whole molecule is involved in the interaction, the C-terminus plays an important role. The elution order of DDD- and LLL-TFA-Ala-Ala-Ala-OMe is opposite to the order of the enhalpy values, and the ratio of net retention data t’r(DDD)/t’r(LLL) is increased with increasing temperature. By lowering the temperature, peak crossing of the enantiomeric pair has been observed. Below the isoselective temperature Tiso’ the order of elution is ruled by the enthalpy of interaction, above Tiso by the entropy of interaction.

关键词： gas chromatography enantiomer resolution oligopeptides Chirasil-Val thermodynamic analysis reversal of peak order.

Detection of FPGS mRNA expression in methotrexate enantiomer-resistant A549 cell by a real-time PCR method

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Detection of FPGS mRNA expression in methotrexate enantiomer...

Aldehyde oxidase mediated enantioselective metabolic health risk of dinotefuran

中国生物化学与分子生物学会第十届会员代表大会暨全国学术...

作者： Li Sun Xiaodong He Zuojun Shen Affiliated provincial hospital of Anhui Medical University Anhui Provincial center for clinical Laboratories Anhui provincial hospital

Objective:To explored the change of folylpolyglutamate synthetase(FPGS)mRNA in enantiomerresistant cells,by real-time PCR method,so that further research on drug resistant mechanism of the tumor could be carried ***:Two kinds of drug resistant A549 lung cancer cell strains(L-(+)-MTX,D-(-)-MTX),with the concentration of drug resistance is 25μmol/L,were chosen as subjects in the experiment,compared with MTX-sensitive cell *** the expression of FPGS mRNA were assayed by real - time ***:The standard curves which correlation coefficients were respectively 0.9987 and 0.9968 were established for detecting FPGS among 1×10-4and 1×*** the melting peaks were *** real time-PCR,the△Ct were respectively -2.45±0.44、-4.26±0.18、0.15±0.02 in parent cells、L-(+)- MTX/A549 cells and D-(-)-MTX/A549 *** difference in these three teams were all significant(Penantiomer-resistant cells (Penantiomer-resistant cells.

关键词： Real-time fluorescent quantitative polymerase chain reaction Methotrexate enantiomer Folylpolyglutamate synthetase

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Science China Chemistry 2024年第6期67卷 2079-2091页

作者： Liwei Xu Xinxin Xu Hua Kuang Chuanlai Xu Xiaoling Wu State Key Laboratory of Food Science and Resources Jiangnan UniversityWuxi214122China International Joint Research Laboratory for Biointerface and Biodetection and School of Food Science and Technology Jiangnan UniversityWuxi214122China Collaborative Innovation center of Food Safety and Quality Control in Jiangsu Province Jiangnan UniversityWuxi214122China

Chiral pollutants often pose significant differential environmental health *** this study,the biotransformation of chiral dinotefuran(DIN)and its enantioselective metabolic toxicity mechanisms have been systemically ***,reversedphase chromatography-high resolution mass spectrometry was developed to quantify the content of DIN R/S chiral enantiomer with pg level sensitivity,revealing a lower elimination rate constant(K_(e))of S-DIN(0.730 h^(-1))than R-DIN(0.746 h^(-1)).Secondly,the interaction mechanism between DIN metabolism and important endogenous bioactive molecules,such as aldehyde oxidase(AOX)and neurotransmitters,was *** DIN nitro-group was converted into a guanidine group by the reducing site of nearby flavin adenine dinucleotide(FAD)in AOX with the preferred higher affinity of ***,the endogenous tryptophan(Trp)aldehyde metabolic intermediate,5-hydroxyindoleacetaldehyde(5-HIAL),provides a persistent electron donor for DIN reduction via the oxidation-catalyzed site in AOX,resulting in remarkable up-regulation of monoamine neurotransmitters such as serotonin and ***,the higher level of neurotransmitters further mediated dysregulation of oxylipin homeostasis via the serotonergic pathway,where S-DIN exhibited more pronounced liver lipid damage and environmental health risk with the accumulated lipid biomarkers,oxidized triglyceride(OxTG)and oxidized sphingomyelin(OxSM).This study elucidates the AOX-mediated enantioselectivity metabolic pathway of DIN,providing a new analytical method for chiral pollutants and paves the way for their health risk assessments.

关键词： neonicotinoid dinotefuran enantiomer aldehyde oxidase metabolomics health risk

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Synthesis and characterization of the two enantiomers of a chiral sigma-1 receptor radioligand:(S)-(+)-and(R)-(-)-[^(18)F]FBFP

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Chinese Chemical Letters 2022年第7期33卷 3543-3548页

作者： Tao Wang Ying Zhang Xiaojun Zhang Leyuan Chen Mingqiang Zheng Jinming Zhang Peter Brust Winnie Deuther-Conrad Yiyun Huang Hongmei Jia Key Laboratory of Radiopharmaceuticals(Beijing Normal University) Ministry of EducationCollege of ChemistryBeijing Normal UniversityBeijing 100875China Nuclear Medicine Department The First Medical Center of Chinese PLA General HospitalBeijing 100853China Institute of Radiation Medicine Peking Union Medical College&Chinese Academy of Medical SciencesTianjin 300192China Yale PET Center Department of Radiology and Biomedical ImagingYale University School of MedicineNew HavenCT 06520-8048United States Helmholtz-Zentrum Dresden-Rossendorf Institute of Radiopharmaceutical Cancer ResearchDepartment of NeuroradiopharmaceuticalsLeipzig 04318Germany The Lübeck Institute of Experimental Dermatology University Medical Center Schleswig-HolsteinLubeck 23562.Germany

Racemic[^(18)F]FBFP([^(18)F]1)proved to be a potentσ_(1) receptor radiotracer with superior imaging *** pure enantiomers of unlabeled compounds(S)-and(R)-1 and the corresponding iodonium ylide precursors were synthesized and *** two enantiomers(S)-1 and(R)-1 exhibited comparable high affinity forσ_(1) receptors and selectivity overσ_(2) *** Ca^(2+) fluorescence assay indicated that(R)-1 behaved as an antagonist and(S)-1 as an agonist forσ_(1) *** ^(18)F-labeled enantiomers(S)-and(R)-[^(18)F]1 were obtained in>99%enantiomeric purity from the corresponding enantiopure iodonium ylide precursors with radiochemical yield of 24.4%±2.6%and molar activity of 86–214 GBq/μ*** ICR mice both(S)-and(R)-[^(18)F]1displayed comparable high brain uptake,brain-to-blood ratio,in vivo stability and binding specificity in the brain and peripheral *** micro-positron emission tomography(PET)imaging studies in rats,(S)-[^(18)F]1 exhibited faster clearance from the brain than(R)-[^(18)F]1,indicating different brain kinetics of the two ***(S)-and(R)-[^(18)F]1 warrant further evaluation in primates to translate a single enantiomer with more suitable kinetics for imaging theσ_(1) receptors in humans.

关键词： σ_(1)receptor enantiomer Radiotracer Positron emission tomography Fluorine-18

enantiomeric Cephalotaxus alkaloids from seeds of Cephalotaxus oliveri

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Natural Products and Bioprospecting 2022年第1期12卷 360-366页

作者： Guang-Xing Yu Jing Wu Bao-Bao Shi Mei-Fen Bao Xiang-Hai Cai 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 100039People’s Republic of China

Five undescribed alkaloids were isolated from the seeds of Cephalotaxus oliveri along with 27 known *** new structures were elucidated based on spectroscopic data including 1D and 2D NMR,MS and calculated ECD *** them,(+)-acetylcephalofortine C was an enantiomeric Cephalotaxine *** performed bioassay revealed that those alkaloids were not cytotoxic against cancer cells and had no neuroprotective properties in the HEI-OC-1 cells model.

关键词： Cephalotaxus oliveri Cephalotaxaceae Alkaloid enantiomer

Isolation of Single-Walled Carbon Nanotube enantiomers by Density Differentiation

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Nano Research 2009年第1期2卷 69-77页

作者： Alexander A.Green Matthew C.Duch Mark C.Hersam Department of Materials Science and Engineering and Department of Chemistry Northwestern UniversityEvanstonIllinois 60208-3108USA

Current methods of synthesizing single-walled carbon nanotubes(SWNTs)result in racemic mixtures that have impeded the study of left-and right-handed *** we present a method of isolating different SWNT enantiomers using density gradient *** separation is enabled by the chiral surfactant sodium cholate,which discriminates between left-and right-handed SWNTs and thus induces subtle differences in their buoyant *** sorting strategy can be employed for simultaneous enrichment by handedness and roll-up vector of SWNTs having diameters ranging from 0.7 to 1.5 *** addition,circular dichroism of enantiomer refined samples enables identification of high-energy optical transitions in SWNTs.

关键词： Carbon nanotube separation handedness enantiomer optical activity chirality

Development of a UHPLC-MS/MS method for the quantification of ilaprazole enantiomers in rat plasma and its pharmacokinetic application

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Journal of Pharmaceutical Analysis 2020年第6期10卷 617-623页

作者： Fengting Ou Ying Zhou Jinxiu Lei Su Zeng Fuhai Wu Ning Zhang Lushan Yu Institute of Drug Metabolism and Pharmaceutical Analysis College of Pharmaceutical SciencesZhejiang UniversityHangzhou310058China School of Pharmacy Guangdong Pharmaceutical UniversityGuangdong510006China School of Public Health Guangdong Pharmaceutical UniversityGuangdong510006China Institute of Nuclear Agricultural Sciences Zhejiang UniversityHangzhou310058China

In Korea and China,ilaprazole is a widely used proton pump inhibitor in the treatment of gastric *** this study,a specific and sensitive LC-MS/MS method has been developed and validated for the quantification of ilaprazole enantiomers in the rat plasma,using R-lansoprazole as the internal *** enantioseparation was achieved on a CHIRALPAK AS-RH column(4.6 mm×150 mm,i.d.5 mm),with a mobile phase composed of 10 m M ammonium acetate aqueous solution and acetonitrile(60:40,V/V),at a flow-rate of 0.5 m L/*** method was validated over the concentration range of 0.5 e300 ng/m L for both,R-and *** lower limit of quantification was 0.5 ng/m L for both *** relative standard deviation(RSD)of intra-and inter-day precision of R-ilaprazole and S-ilaprazole was less than 10.9%,and the relative error accuracy(RE)ranged fromà0.5%e2.0%.Finally,the method was successfully evaluated in rats in a stereoselective pharmacokinetic study of the ilaprazole racemate.

关键词： Ilaprazole enantiomer LC-MS/MS Pharmacokinetics

Facile Synthesis of enantiomerically Pure 1-（5-Bromo-2-chlorophenyl）-1-（4-ethoxyphenyl）ethane

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Chemical Research in Chinese Universities 2014年第2期30卷 250-256页

作者： ZHANG Shuo WANG Wenjin LI Chuan LIU Peng XU Weiren TANG Lida WANG Jianwu ZHAO Guilong School of Chemistry and Chemical Engineering Shandong University Jinan 250100 P.R.China Tianjin Key Laboratory of Molecular Design and Drug Discovery Tianjin Institute of Pharmaceutical ResearchTianjin 300193 P.R.China

A facile 7-step procedure for the synthesis of enantiomerically pure 1-（5-bromo-2-chlorophenyl）-1-（4-ethoxyphenyl）ethanes[（R）-2 and（S）-2] that started from （5-bromo-2-chlorophenyl）（4-ethoxyphenyl）methanone 3 was *** key step was the resolution of 2-（5-bromo-2-chlorophenyl）-2-（4-ethoxyphenyl）acetic acid 6 by crystallizations of its L-and D-menthyl esters 7 and 8 from petroleum ether to give optically pure enantiomers 9 and 10,*** absolute configurations of the products were unambiguously determined by single-crystal X-ray diffractions of four key intermediates,9,10,13 and *** procedure is characterized by inexpensiveness,scalability and ability to produce two individual enantiomers of a diarylethane with unambiguously determined absolute configurations and high enantiomeric purities.

关键词： Diarylethane Diastereomer enantiomer Resolution SGLT2 inhibitor