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Aldehyde oxidase mediated enantioselective metabolic health risk of dinotefuran

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 risks.In this study,the biotransformation of chiral dinotefuran(DIN)and its enantioselective metabolic toxicity mechanisms have been systemically investigated.Firstly,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 revealed.The 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 S-configuration.Meanwhile,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 dopamine.Thirdly,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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enantiomer separation by CEC——enantiomer separation by packed-capillary electrochromatography

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Science China Chemistry 1999年第5期42卷 511-519页

作者：朱军邹汉法施维芮建中倪坚毅张玉奎 Natl. Chromatographic Res./Anal. C. Dalian Institute of Chemical Physics Chinese Academy of Sciences Dalian 116011 China

Three chiral compounds were successfully separated in a short time with two enantiomer separation models on packed-capillary electrochromatography (CEC). (i) 75 μm I.D. capillaries were packed with 5 μm β-cyclodextrin (β-CD) chiral stationary phase (CSP). Effects of voltage, pH and concentration of organic modifier on electroosmotic flow (EOF) and chiral separations were investigated systematically. enantiomers of a neutral compound (benzoin) and a neutral drug (mephenytoin) were separated within a short time with high efficiency. Efficiency of 32 000 theoretical plates per meter and resolution (R_s) of 1.42 were achieved for enantiomers of benzoin using a βCD packed column with 6.2 cm packed length. Efficiency of 45 000 theoretical plates per meter and R_s of 3.40 were obtained for enantiomers of mephenytoin. Especially, the enantiomer separation of mephenytion was performed in just 3.4 min with R_s of 2.60. (ⅱ) 75 μm I.D. capillary was packed with octadecylsilica particles (ODS). Chiral

关键词： packed-capillary electrochromatography enantiomer separation chiral selector fast analysis high efficiency resolution.

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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.

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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 ones.The new structures were elucidated based on spectroscopic data including 1D and 2D NMR,MS and calculated ECD spectra.Among them,(+)-acetylcephalofortine C was an enantiomeric Cephalotaxine alkaloids.The 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

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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 properties.The pure enantiomers of unlabeled compounds(S)-and(R)-1 and the corresponding iodonium ylide precursors were synthesized and characterized.The two enantiomers(S)-1 and(R)-1 exhibited comparable high affinity forσ_(1) receptors and selectivity overσ_(2) receptors.The Ca^(2+) fluorescence assay indicated that(R)-1 behaved as an antagonist and(S)-1 as an agonist forσ_(1) receptors.The ^(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/μmol.In 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 organs.In 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 enantiomers.Both(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

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Three pairs of alkaloid enantiomers from the root of Isatis indigotica

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Acta Pharmaceutica Sinica B 2016年第2期6卷 141-147,188页

作者： Yufeng Liu Xiaoliang Wang Minghua Chen Sheng Lin Li Li 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 College Department of Pharmacy Jining Medical University Institute of Medicinal Biotechnology Chinese Academy of Medical Sciences and Peking Union Medical College

Three pairs of enantiomerically pure alkaloids with diverse structure features, named isatindigoticoic acid A and epiisatindigoticoic acid A [(—)-1 and(+)-1], phaitanthrin A and epiphaitanthrin A [(—)-2 and(+)-2], and isatindopyrromizol A and epiisatindopyrromizol A [(—)-3and(+)-3], respectively, were isolated from an aqueous extract of the roots of Isatis indigotica. Racemic and scalemic mixtures of these enantiomers were separated by HPLC on a chiral semi-preparative column.Their structures including absolute configurations were determined by extensive spectroscopic analysis in conjunction with the calculation of electronic circular dichroism(ECD) spectra. The enantiomer pairs possess parent structures of 2-oxo-1,2,3,4-tetrahydroquinoline-4-carboxylic acid, indolo[2,1-b]quinazolinone, and 3-thioxohexahydro-1H-pyrrolo[1,2-c]imidazol-1-one, respectively. Except for phaitanthrin A[(—)-2] which the configuration was previously undetermined, these compounds are new enantiomeric natural products.

关键词： Cruciferae Isatis indigotica Alkaloid enantiomer Chiral separation 2-Oxo-1,2,3,4-tetrahydroquinoline-4-carboxylic acid Indolo[2,1-b]quinazolinone 3-Thioxohexahydro-1H-pyrrolo[1,2-c]imidazol-1-one

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Significance and challenges of stereoselectivity assessing methods in drug metabolism

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Journal of Pharmaceutical Analysis 2016年第1期6卷 1-10页

作者： Zhuowei Shen Chuang Lv Su Zeng Institute of Drug Metabolism and Pharmaceutical Analysis Zhejiang Province Key Laboratory of Anti-Cancer Drug Research College of Pharmaceutical Sciences Zhejiang University Biogen Idec Cambridge

Stereoselectivity in drug metabolism can not only influence the pharmacological activities, tolerability, safety, and bioavailability of drugs directly, but also cause different kinds of drug-drug interactions. Thus, assessing stereoselectivity in drug metabolism is of great significance for pharmaceutical research and development （R＆D） and rational use in clinic. Although there are various methods available for assessing stereoselectivity in drug metabolism, many of them have shortcomings. The indirect method of chro- matographic methods can only be applicable to specific samples with functional groups to be derivatized or form complex with a chiral selector, while the direct method achieved by chiral stationary phases （CSPs） is expensive. As a detector of chromatographic methods, mass spectrometry （MS） is highly sen- sitive and specific, whereas the matrix interference is still a challenge to overcome. In addition, the use of nuclear magnetic resonance （NMR） and immunoassay in chiral analysis are worth noting. This review presents several typical examples of drug stereoselective metabolism and provides a literature-based evaluation on current chiral analytical techniques to show the significance and challenges of stereo- selectivity assessing methods in drug metabolism.

关键词： enantiomer Chiral chromatography Capillary electrophoresis Mass spectrometry NMR Immunoassay

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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 ulcers.In 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 standard.The 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/min.The method was validated over the concentration range of 0.5 e300 ng/m L for both,R-and S-ilaprazole.The lower limit of quantification was 0.5 ng/m L for both enantiomers.The 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

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A novel D(−)-lactic acid-inducible promoter regulated by the GntR-family protein D-LldR of Pseudomonas fluorescens

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Synthetic and Systems Biotechnology 2019年第3期4卷 157-164页

作者： Kalpana Singh Satish Kumar Ainala Yeonhee Kim Sunghoon Park School of Energy and Chemical Engineering UNISTUlsan44919Republic of Korea School of Chemical and Biomolecular Engineering Pusan National UniversityBusan46241Republic of Korea

Lactic acid has two stereoisomers of D(−)-and L(+)-forms,both of which are important monomers of biodegradable plastic,poly-lactic acid.In this study,a novel D-lactate inducible system was identified in Pseudomonas fluorescens A506,partially characterized and tested as biosensor.The D-lactate catabolic operon(lldP-dld-II)was negatively regulated through the inversely transcribed D-lldR(encoding a GntR-type regulator),where the repression is relieved by addition of D-lactate.The derepression was specific to D-lactate and marginally affected by L-lactate.The D-LldR-responsive operator,showing dyad symmetry and separated by one base,was located between+11 and+27 from the transcription start site of the lldP-dld-II operon.By site-directed mutagenesis,a motif with a dyad symmetry(AATTGGTAtTACCAATT),present in the upstream region of lldP,was identified as essential for the binding of LldR.D-lactate biosensors were developed by connecting the upregulation by D-lactate to a green fluorescent readout.About^6.0-fold induction by 100mM D-lactate was observed compared to Llactate.

关键词： Lactic acid enantiomer Biosensor Repression

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Slow-release praziquantel for dogs:presentation of a new formulation for echinococcosis control

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Infectious Diseases of Poverty 2017年第1期6卷 1244-1254页

作者： Bin Jiang Xiao-Nong Zhou Hao-Bing Zhang Yi Tao Le-Le Huo Ni Liu National institute of parasitic Diseases Chinese Center for Disease Control and Prevention207 Ruijin Er RoadShanghai 200025China Key Laboratory of Parasite and Vector Biology Ministry of Health207 Ruijin Er RoadShanghai 200025China National Center for International Research on Tropical Diseases Ministry of Science and Technology207 Ruijin Er RoadShanghai 200025China WHO Collaborating Centre for Tropical Diseases 207 Ruijin Er RoadShanghai 200025China

Background:Echinococcosis is a serious,zoonotic,parasitic disease with worldwide distribution.According to a epidemiological survey in 2012 in China,there are 20,000 infected patients and more than 50 million people at the risk.As the dog is the main,definitive host,the Government of China encourages monthly praziquantel treatment of every dog.However,this is difficult to achieve in geographically challenging areas,such as the Tibetan plateau,where there are also many dogs without owners.To overcome these problems,we investigated the transmission blocking capacity of a slow-release formulation of praziquantel administered by subcutaneous injection.Methods:The impact of a slow-release preparation of two pharmacokinetically stereoselective praziquantel enantiomers,i.e.,R-(−)-praziquantel(R-PZQ)and S-(+)-praziquantel(S-PZQ)absorbed into a biodegradable polymer was studied in beagle dogs(N=6).The preparation was given by subcutaneous injection using a single dose of 100 mg/kg.Chiral-selective,high-performance liquid chromatography(HPLC)and high-resolution mass spectrometry(HRMS)were applied to measure the praziquantel enantiomers in the plasma of the dogs.The lower limit for estimating plasma concentrations accurately for R-PZQ was 4 ng/ml and for S-PZQ 20 ng/ml.The pharmacokinetic parameters were calculated by a noncompartmental analysis model using Drug Analyze System(DAS)software 2.0.The SPSS 19.0 software was used for statistical analysis,and the statistical comparison between enantiomers was assessed using the two-tailed t-test.Results:Two hours after administration,peak concentrations of R-PZQ and S-PZQ:321±26 and 719±263 ng/ml,respectively,were achieved.After 180 days,the average plasma concentration of R-PZQ in the six dogs had decreased to 13 ng/ml.The average concentration value of S-PZQ was higher than that of R-PZQ in the first 90-day period but fell afterwards and could not be accurately estimated when dropping below 20 ng/ml(the lower methodological limit for this enantiomer).Taking all the dogs into ac

关键词： Echinococcus Transmission-blocking Praziquantel enantiomer In situ slow-release preparation Subcutaneous injection Pharmacokinetic Stereoselective Dog China

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