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Chinese Chemical Letters 2022年第12期33卷 4969-4979页

作者： Ming Bao Su Zhou Wenhao Hu xinfang xu Guangdong Key Laboratory of Chiral Molecule and Drug Discovery School of Pharmaceutical SciencesSun Yat-sen UniversityGuangzhou 510006China

Homogeneous gold catalysis has demonstrated the preponderant capability of realizing a broad range of synthetically versatile alkyne functionalization over the last two *** catalytic asymmetric alkyne transformation has focused on the principle of using gold catalysts either associated with chiral phosphine ligand or combined with chiral counterion,a variety of breakthroughs have been reported with the application of gold-complex and chiral organocatalyst cooperative catalysis strategy,which could enable the challenging transformations that cannot be realized by mono-catalysis with excellent *** review will cover two general protocols in this field,including relay catalysis and synergistic catalysis,with emphasis on the detailed cooperative catalysts models to illustrate the roles of the two catalysts and highlight the potential synthetic opportunities offered by asymmetric cooperative catalysis.

关键词： Gold catalysis Chiral organocatalyst catalysis Relay catalysis Synergistic catalysis Asymmetric alkyne functionalization

Gold-catalyzed ketene dual functionalization and mechanistic insights:divergent synthesis of indenes and benzo[d]oxepines

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Science China Chemistry 2021年第5期64卷 778-787页

作者： Ming Bao Jinzhou Chen Chao Pei Sujie Zhang Jinping Lei Wenhao Hu xinfang xu Guangdong Provincial Key Laboratory of Chiral Molecule and Drug Discovery School of Pharmaceutical SciencesSun Yat-sen UniversityGuangzhou 510006China

An unprecedented gold-catalyzed ketene C=O/C=C bifunctionalization method has been *** studies and density function theory(DFT)calculations indicate that the reaction is initiated by gold-catalyzed Wolff rearrangement of diazoketone to form the ketene intermediate,followed by intermolecular nucleophilic addition and terminated with two divergent cyclization processes via enol *** the case with alcohols as the nucleophiles,the reaction goes through a C-5-endodig carbocyclization to give the indene products;whereas,O-7-endo-dig cyclization occurs dominantly when indoles/pyrroles are used as the nucleophiles,delivering the 7-membered benzo[d]*** comparison with the well-documented cycloaddition and nucleophilic addition reactions,this cascade reaction features a novel reaction pattern for the ketene dual functionalization through addition with nucleophile and electrophile in sequence.

关键词： metal carbene ketene dual functionalization Wolff rearrangement gold catalysis indene benzo[d]oxepine

Prediction rule for estimating advanced colorectal neoplasm risk in average-risk populations in southern Jiangsu Province

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Chinese Journal of Cancer Research 2014年第1期26卷 4-11页

作者： Guochang Chen Boneng Mao Qi Pan Qian Liu xinfang xu Yueji Ning Department of Gastroenterology Affiliated Hospital of Jiangsu University

Objective：The aim of this study was to establish the risk scoring system towards the advanced colorectal neoplasm （CN） risk in the average-risk populations in the southern Jiangsu Province,and to evaluate the screening ***：Totally 905 cases of the average-risk populations who received the colonoscopy were selected as the *** multivariate logistic regression analysis method was used to establish the scoring system towards the occurrence risk of the advanced tumor,and its screening efficacy was evaluated through the prediction consistency,distinguishing ability and screening ***：The scoring system consisted of five variables,namely age,gender,coronary heart disease,egg intake and stool *** results revealed that it had good prediction consistency （P=0.205） and distinguishing ability [the area under the receiver operating characteristic （ROC） curve was 0.75,with 95％ confidence interval （95％ CI） of 0.69-0.82].Thus,2.5 points was set as the screening cutoff value,and its sensitivity,specificity,accuracy,positive predictive value,negative predictive value,positive likelihood ratio and negative likelihood ratio were 93.8 ％,47.6％,50.1％,9.1％,99.3％,1.79 and 0.13,***：The established scoring system had good screening efficacy,and can be used as the screening tool applying to the CN screening within the average-risk populations in the southern Jiangsu Province.

关键词： Colorectal neoplasm (CN) colonoscopy cross-sectional studies screening risk factor

Asymmetric Three-Component Propargyloxylation for Direct Assembly of Polyfunctionalized Chiral Succinate Derivatives

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CCS Chemistry 2021年第7期3卷 1903-1912页

作者： Xinxin Lv Shuhao Liu Su Zhou Guizhi Dong Dong Xing xinfang xu Wenhao Hu Guangdong Provincial Key Laboratory of Chiral Molecule and Drug Discovery School of Pharmaceutical SciencesSun Yat-sen UniversityGuangzhou 510006 School of Chemistry and Chemical Engineering Henan Normal UniversityXinxiangHenan 453007 Shanghai Engineering Research Center of Molecular Therapeutics and New Drug Development School of Chemistry and Molecular EngineeringEast China Normal UniversityShanghai 200062

An enantioselective three-component propargyloxylation reaction of propargyl alcohols,pyridotriazoles,and imines has been realized by cooperative catalysis with dirhodium complex and chiral phosphoric acid under mild *** is the first example of a catalytic asymmetric three-component propargyloxylation reaction,which provides practical access to chiral polyfunctionalized succinate derivatives with adjacent quaternary and tertiary stereocenters in good to high yields with excellent *** addition to the alkyne motif,pyridyl,alkoxy,amino,and alkenyl species are all tolerated under the reaction ***,the utility of the current method is demonstrated by catalytic cyclization of the product alkyne into a variety of heterocyclic structures without loss of enantiomeric purity.

关键词： asymmetric multicomponent reaction asymmetric propargyloxylation cooperative catalysis metal carbene chiral succinate derivative alkyne

Highly Enantioselective Trapping of Carboxylic Oxonium Ylides with Imines for Direct Assembly of Enantioenriched γ-Butenolides

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CCS Chemistry 2020年第4期2卷 432-439页

作者： Dan Zhang Xin Wang Mengchu Zhang Zhenghui Kang Guolan Xiao xinfang xu Wenhao Hu Guangdong Key Laboratory of Chiral Molecule and Drug Discovery School of Pharmaceutical SciencesSun Yat-Sen UniversityGuangzhou 510006

Enantioenrichedγ-butenolides are valuable structural cores in many pharmaceuticals and natural products,but their direct and catalytically asymmetric assembly remains ***,we report an efficient,atom-economic synthetic strategy for enantioenrichedγ-butenolides via a unique enantioselective reaction of cyclopropene carboxylic acids with imines under the synergistic catalysis of Rh2(esp)2/chiral Brønsted acid *** reaction involved trapping of carboxylic oxonium ylides,generated from cyclopropene carboxylic acids,which presented as the first asymmetric trapping reactive intermediate in the process.

关键词： cyclopropenes vinyl carbenes ylides asymmetric catalysis γ-butenolides

铜催化炔烃-联烯酮的区域和对映选择性控制的共轭还原

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有机化学 2021年第7期41卷 2916-2917页

作者：姚铭瀚徐新芳中山大学药学院广州510006

不对称转移氢化反应是有机合成中高效构建手性分子的重要方法之一[1-4].目前,过渡金属催化α,β-不饱和类化合物的不对称氢化已经取得了突破性的进展,包括α,β-不饱和羧酸、酯、酰胺、酮、芳基或者烷基取代的烯烃以及炔烃的氢化等[5].... 详细信息

不对称转移氢化反应是有机合成中高效构建手性分子的重要方法之一[1-4].目前,过渡金属催化α,β-不饱和类化合物的不对称氢化已经取得了突破性的进展,包括α,β-不饱和羧酸、酯、酰胺、酮、芳基或者烷基取代的烯烃以及炔烃的氢化等[5].其中很多方法依赖于贵金属催化剂,包括Rh、Ru、Ir和Pd等手性配合物[6].这些贵金属催化剂一方面使得转化方法的成本提高,另一方面也对环境和公众健康构成一定的影响.与上述贵金属催化剂相比,手性铜催化剂具有廉价、低毒、绿色和可持续性的优点,并且已被证明在不对称催化氢化中是有效的[7-8].因此,发展绿色、高效、低成本的铜催化的不对称氢化逐渐受到更多关注.

关键词：不对称氢化贵金属催化剂手性分子过渡金属催化手性配合物炔烃不饱和羧酸对映选择性

REGIONAL ASSIGNMENT OF HUMAN ALCOHOL DEHYDROGENASE (ADH) GENE TO 4pter→4q21

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Science in China,Ser.B 1987年第7期30卷 720-726页

作者：徐一玲薛京伦邱信芳祁鸣徐芸 Institute of Genetics Fudan University Shanghai

The hybrid clone FD1 constructed by fusion of Chinese hamster cell line Wg3-h with human lymphocyte was irradiated with X-ray. Fourteen survival clones were isolated and 3 of them, F5B, F52B, F61A were analyzed in detail by cytogenetic and biochemical methods. The results of chromosome Gbanding followed by Giemsa-11 differential staining show that there exists a deleted human chromosome 4 in all of the three hybrids. This deletion of human chromosome 4 in F61A is 4pter→4q21. The results of isozyme analysis of phosphoglucomutase-2 （PGM2） which is located on 4p14→4q21 confirm our cytogenetic conclusion. We used polyaerylamide gel electrophoresis to study the alcohol dehydrogenase （ADH） in human lymphocyte, Wg3-h and hybrid clones. Their electrophoretic pattern showed that human ADH isozyme did express, in the peripheral blood lymphocyte, hybrids FSB, F52B, F61A and FD1. According to these results, we suggest that one of the Class 1 ADH structural genes is located on the human chromosome 4pter→4q21. Rec

关键词： ADH GENE TO 4pter REGIONAL ASSIGNMENT OF HUMAN ALCOHOL DEHYDROGENASE

双核铑催化炔烃作为卡宾前体的不对称双环丙烷化反应

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有机化学 2023年第8期43卷 2977-2979页

作者：熊唯辰徐新芳中山大学药学院广州510000006

手性双环丙烷是许多天然产物和生物活性分子的重要骨架[1].然而,由于存在多个立体中心,合成这些具有高立体选择性的分子的途径很少.通常,共轭二烯的双环丙烷化(Scheme 1,A)和1,n-烯炔的环异构化反应(Scheme 1,B)是构建这类独特骨架的两... 详细信息

手性双环丙烷是许多天然产物和生物活性分子的重要骨架[1].然而,由于存在多个立体中心,合成这些具有高立体选择性的分子的途径很少.通常,共轭二烯的双环丙烷化(Scheme 1,A)和1,n-烯炔的环异构化反应(Scheme 1,B)是构建这类独特骨架的两种策略[2-3].

关键词：立体选择性环丙烷化共轭二烯天然产物生物活性分子烯炔铑催化炔烃

A Direct Access to the Polycyclic Ring Structures via Intramolecular Metal Carbene Cascade Reactions

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A Direct Access to the Polycyclic Ring Structures via Intram...

协同活化策略实现双核铑催化的不对称烯炔环异构化反应

中国化学会全国第十二届有机合成化学学术研讨会

作者： Wang,Xiangbo Zheng,Yang Qiu,Lihua xu,xinfang Key Laboratory of Organic Synthesis of Jiangsu Province

Polycyclic ring structures are pervasive unit in nature products and pharmaceutical *** methods have been developed for the effective construction of the ring systems with various frameworks,the synthetic potential of development efficient cascade reactions access to these structures is contiuning to become ***,we disclosed a new type of metal carbene cascade reaction of alkynyl tethered diazoacetates,which proceeds through initial metal carbene formation via catalytic diazo decomposition,carbene/alkyne metathesis,and terminated with typical metal carbene *** proposed strategy is a versatile and direct access to the polycyclic ring structures from the alkyne tethered diazo compounds by simply switching the built in linkers（purple） and terminating groups（green）,and chiral polycyclic rings with structure diversity,including various heterocycles,could be envisioned via this methodology.

关键词： cascade reaction metal carbene/alkyne metathesis asymmetric catalysis

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有机化学 2020年第12期40卷 4370-4371页

作者：刘向荣徐新芳胡文浩中山大学药学院广州510006

炔烃作为一类廉价易得的化学原料,在合成化学中是一种非常有用的有机合成砌块.因此,炔烃叁键的催化官能团化反应作为一类非常实用的有机化学反应备受关注[1].在近几十年中,系列新颖的炔烃催化官能团化反应被发现,并在许多生物活性分子... 详细信息

炔烃作为一类廉价易得的化学原料,在合成化学中是一种非常有用的有机合成砌块.因此,炔烃叁键的催化官能团化反应作为一类非常实用的有机化学反应备受关注[1].在近几十年中,系列新颖的炔烃催化官能团化反应被发现,并在许多生物活性分子的合成中得到应用.其中以炔烃作为卡宾前体,随后发生卡宾转移反应是实现炔烃催化官能团化的重要手段.

关键词：有机化学反应转移反应合成化学炔烃卡宾生物活性分子烯炔铑催化