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Recent advances in new trifluoromethoxylation reagents

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Science China Chemistry 2019年第5期62卷 525-532页

作者： Xiaofei Zhang pingping tang State Key Laboratory and Institute of Elemento-Organic Chemistry College of ChemistryNankai UniversityCollaborative Innovation Center of Chemical Science and Engineering (Tianjin)

The trifluoromethoxy(CF_3O) group has become a novel moiety in various fields because of its unique features. However, despite the promising applications, the synthesis of CF_3O-containing compounds is still a challenge due to indirect synthetical strategies and volatile reagent which is hard to handle. Until very recently, several innovative reagents were developed to facilitate the trifluoromethoxylation reaction and make CF_3O-containing compounds more accessible. This review mainly focuses on the recent advances in new trifluoromethoxylation reagents and their usage.

关键词： trifluoromethoxy group trifluoromethoxylation reagent synthetic methods fluorine

Recent Advances of Trifluoromethoxylation Reactions Using TFMS and TFBO

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Chinese Journal of Chemistry 2021年第2期39卷 255-264页

作者： Xiaohuan Jiang pingping tang State Key Laboratory and Institute of Elemento-Organic Chemistry College of ChemistryNankai UniversityTianjin300071 China

The OCF_(3)group has good metabolic stability,suitable lipophilicity and special electrical properties,which can modify the properties of drugs and material molecules.In recent years,trifluoromethoxy compounds have received more and more attention.Both new reagents and new trifluoromethoxylation strategies got a breakthrough.Our group has been committed to the development of trifluoromethoxylation reagents and methods.This account focuses on describing various trifluoromethoxylation reactions with trifluoromethyl sulfonates(TFMS)and(E)-O-trifluoromethyl-benzaldoximes(TFBO)developed by our group.

关键词： Trifluoromethoxylation reagents Fluorine Carbocations Radicals Synthetic methods

A Fruitful Decade of Organofluorine Chemistry: New Reagents and Reactions

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CCS Chemistry 2022年第8期4卷 2518-2549页

作者： Feng-Ling Qing Xin-Yuan Liu Jun-An Ma Qilong Shen Qiuling Song pingping tang Key Laboratory of Organofluorine Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032 Shenzhen Grubbs Institute Department of ChemistryGuangdong Provincial Key Laboratory of CatalysisSouthern University of Science and TechnologyShenzhen 518055 Department of Chemistry Tianjin UniversityTianjin 300072 Institute of Next Generation Matter Transformation College of Chemical EngineeringHuaqiao UniversityFujian 361021 State Key Laboratory Institute of Elemento-Organic ChemistryCollege of ChemistryNankai UniversityTianjin 300071

The development of synthetic methods for the introduction of the fluorine atom and fluoroalklyl groups into organic molecules has gained increased attention.Synthetic organic chemists have recently jumped into the field of organofluorine chemistry and have thus made significant contributions.Furthermore,these newly developed methods are typically safer and more effective than the traditional methods.In this review,wewill summarize the representative contributions of new reagents and reactions developed in the past decade.

关键词： fluorination fluoroalkylation reagent reaction fluorine chemistry

Advances in Enantioselective Construction of Trifluoromethoxylated Stereogenic Carbon Centers

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Chinese Journal of Chemistry 2020年第1期38卷 101-102页

作者： Xiaohuan Jiang pingping tang State Key Laboratory and Institute of Elemento-Organic Chemistry College of ChemistryNankai UniversityTianjin 300071China

In recent years,the trifluoromethoxy(OCF3)functional group has received extensive attention in phar-maceuticals,agrochemicals and material sciences.However,the methods for the enantioselective syn-thesis of trifluoromethoxylated stereogenic carbon centers are rare owing to the nature of easy decom-position of OCF3 anion and limited OCF3 reagent.And the asymmetric trifluoromethoxylation will be a hot research topic in near future due to the unique biological properties of a single isomer.This article mainly focuses on the recent advances in the enantioselectiveconstruction of trifluoromethoxylated stereogenic carbon centers.

关键词： methoxyl reagent centers

Synthesis of non-classical heteroaryl C-glycosides via Minisci-type alkylation of N‑heteroarenes with 4-glycosyl-dihydropyridines

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Science China Chemistry 2020年第11期63卷 1613-1618页

作者： Qingbing Wang Juan Duan pingping tang Gong Chen Gang He State Key Laboratory and Institute of Elemento-Organic Chemistry College of ChemistryNankai UniversityTianjin 300071China

A radical-mediated method was reported for diastereoselective synthesis of non-classical heteroaryl C-glycosides via Minisci-type alkylation of N-heteroarenes with 4-glycosyl-1,4-dihydropyridine(DHP)reagents.These DHP reagents serve as convenient precursors for various glycosyl radicals under the activation of single electron transfer(SET)oxidation by persulfate and visible light irradiation with or without photocatalyst.

关键词： non-classical C-glycoside Minisci reaction 4-gIycosyl-dihydropyridine

Unveiling metabolic flux changes during acute cold exposure

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Frigid Zone Medicine 2023年第4期3卷 193-195页

作者： pingping tang Henghui Xu Yong Zhang Department of Pharmacology(State-Province Key Laboratories of Biomedicine-Pharmaceutics of China Key Laboratory of Cardiovascular ResearchMinistry of Education)College of PharmacyHarbin Medical UniversityHarbin 150081China State Key Laboratory of Frigid Zone Cardiovascular Diseases(SKLFZCD) Harbin 150081China Research Unit of Noninfectious Chronic Diseases in Frigid Zone Chinese Academy of Medical Sciences2019RU070Harbin 150081China Institute of Metabolic Disease Heilongjiang Academy of Medical ScienceHarbin 150081China

Controlling energy expenditure during acute cold exposure is a fundamental aspect of metabolic dynamics in organisms.However,prior studies on cold-induced thermogenesis faced limitations,primarily focusing on brown adipose tissue(BAT)and lacking precise in vivo flux measurements.This editorial aims to highlight the recent research by Bornstein et al.providing a comprehensive and quantitative insight into the intricate alterations in metabolic flux that drive this phenomenon[1].

关键词： precise primarily limitations

A Survey of Multimedia Big Data

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China Communications 2018年第1期15卷 155-176页

作者： Zaijian Wang Shiwen Mao Lingyun Yang pingping tang The College of Physics and Electronic Information Anhui Normal University Department of Electrical and Computer Engineering Auburn University

Multimedia big data brings tremendous challenges as well as opportunities for multimedia applications/services. In this paper, we present a survey and tutorial for multimedia big data. After discussing the characteristics of multimedia big data such as human-centricity, multimodality, heterogeneity, unprecedented volume, and so on, this paper provides an overview of the state-of-the-art of multimedia big data, reviews the latest related technologies, and discusses the technical challenges. We conclude this paper with a discussion of open problems and future directions.

关键词： Multimedia big data human-cen-tricity heterogeneity machine learning mul-timodality

Collective Synthesis of Schilancidilactones A, B and Schilancitrilactones A, B, C, 20‐epi‐Schilancitrilactone A

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Chinese Journal of Chemistry 2019年第3期37卷 255-268页

作者： Hengtao Wang Liang Wang Yihang Li Xiunan Zhang pingping tang State Key Laboratory and Institute of Elemento-Organic Chemistry College of ChemistryNankai UniversityTianjin 300071China Collaborative Innovation Center of Chemical Science and Engineering Tianjin 300071China

Summary of main observation and conclusion Schisandraceae triterpenoids are novel natural products that contain highly fused ring systems bearing multiple chiral centers surrounding. Some of them exhibit promising bioactivities, such as antitumor, anti‐HIV, etc. In this article, we describe our efforts to the collective total synthesis of schilancidilactones A, B, schilancitrilactones A, B, C, and 20‐epi‐schilancitrilactone A from common precursors. An intramolecular radical cyclization, late‐stage halogenation and AIBN‐mediated or Ni‐catalyzed intermolecular radical cross coupling reaction were employed as the key steps.

关键词： epi multiple stage ring AIBN HIV our

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子宫颈冷刀锥切术对晚期妊娠结局的影响

中华妇产科杂志 2024年第6期59卷 447-453页

作者：吴雨铮任远钟逸锋汤萍萍宋英娜中国医学科学院北京协和医学院北京协和医院妇产科北京100730

目的:探讨子宫颈冷刀锥切术(CKC)对早产及其他妊娠并发症、新生儿结局的影响,并探究早产风险与锥切深度及体积的关系。方法:收集2002年1月至2018年3月于北京协和医院行CKC且术后成功妊娠的272例孕妇(锥切组)的临床资料(包括妊娠结局),以... 详细信息

目的:探讨子宫颈冷刀锥切术(CKC)对早产及其他妊娠并发症、新生儿结局的影响,并探究早产风险与锥切深度及体积的关系。方法:收集2002年1月至2018年3月于北京协和医院行CKC且术后成功妊娠的272例孕妇(锥切组)的临床资料(包括妊娠结局),以2019年1月至12月于北京协和医院产科建档并分娩的1647例孕妇作为对照(对照组),两组中单胎妊娠孕妇分别为264、1589例。比较两组孕妇的早产、胎膜早破及其他妊娠并发症、新生儿结局,并分析锥切深度及体积与CKC术后单胎妊娠孕妇早产风险的关系。结果:(1)一般情况:锥切组孕妇的单胎妊娠率、分娩年龄、产次及辅助生殖技术妊娠的比例分别与对照组比较,差异均无统计学意义(P均>0.05)。(2)早产及胎膜早破:锥切组单胎妊娠孕妇的早产率明显高于对照组[分别为14.8%(39/264)、5.7%(91/1589);χ^(2)=28.397,P0.05)。(4)锥切深度及体积与CKC术后单胎妊娠孕妇的早产风险:与对照组单胎妊娠孕妇的早产率(5.7%,91/1589)比较,当锥切深度>15 mm时锥切组单胎妊娠孕妇的早产率(21.1%,31/147)显著增高(RR=3.682,95%CI为2.541~5.336;P15 mm孕妇比较,差异有统计学意义(RR=3.084,95%CI为1.474~6.453;P=0.001);而锥切体积<2 cm 3孕妇的早产率与锥切体积≥2 cm 3孕妇比较,差异则无统计学意义(RR=1.700,95%CI为0.935~3.092;P=0.077)。结论:CKC会增加术后妊娠的早产、未足月胎膜早破风险,且早产风险与子宫颈锥切深度有关。

关键词：子宫颈冷刀锥切术妊娠末期妊娠结局早产胎膜早破回顾性研究