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copper-Catalyzed 1,2,5-Trifunctionalization of Terminal Alkynes Using SR as a Transient Directing Group for Radical Translocation

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Chinese Journal of Chemistry 2022年第14期40卷 1667-1673,I0002页

作者： Jian Feng Fang Zhang Chenyun Shu Gangguo Zhu Key Laboratory of the Ministry of Education for Advanced Catalysis Materials Department of ChemistryZhejiang Normal University688 Yingbin RoadJinhuaZhejiang 321004China

The first Cu-catalyzed 1,2,5-trifunctionalization of abundant terminal alkynes is realized by merging hydrogen atom transfer and traceless directing strategy with SR as a transient group,delivering highly functionalized aldehydes in moderate to excellent yields with broad substrate scope.The synthetic utility of this method was demonstrated by the gram-scale reaction and downstream transformations of the resultant products.Given the high efficient installation of three different functional groups in a single reaction,it can serve as a very attractive method for rapidly assembling complex molecules from readily available starting materials.

关键词： Radical reaction Alkyne Trifunctionalization Hydrogen atom transfer copper

copper-Initiated Radical Dearomative 2,5-Alkylarylation of Furans via Trihalomethylation/Spirocyclization Cascade

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Chinese Journal of Chemistry 2022年第24期40卷 2893-2899页

作者： Wenkun Luo Kai Jiang Biaolin Yin Key Laboratory of Functional Molecular Engineering of Guangdong Province School of Chemistry and Chemical EngineeringSouth China University of TechnologyGuangzhouGuangdong510640 China Hunan Provincial Key Laboratory of Materials Protection for Electric Power and Transportation School of Chemistry and EngineeringChangsha University of Science and TechnologyChangshaHunan410114 China

Here is an operable and rare strategy for copper-initiated radical dearomative 2,5-alkylarylation of furan. By means of this strategy, we realized the dearomatization of furans to construct spirooxindoles with good yi... 详细信息

关键词： copper Radical reactions Dearomatization Trihalomethylation Spiro compounds

copper-Catalyzed Si-H Bond Insertion Polymerization for Synthesis of Optically Active Polyesters Containing Silicon

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Chinese Journal of Chemistry 2022年第1期40卷 21-27页

作者： Xiao-Yong Zhai Xiao-Qing Wang Bo Wu Yong-Gui Zhou State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalianLiaoning 116023China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China

The synthesis and characterization of chiral polymers with diverse structure remain a long-term challenging research topic.Herein,a copper-catalyzed enantioselective insertion of carbene into Si-H bond was applied to polycondensation,giving a new type of optically active degradable polyesters containing Si-C bond in the main chain.The polymerization features mild condition,broad substrate scope,excellent yields and enantioselectivities.Chiral diols could be obtained via reduction of optically active polyesters.Thermogravimetric analysis indicated these chiral polyesters exhibit good thermal stability.

关键词： Polymerization Insertion Asymmetric catalysis Optically active polyesters copper

copper-Mediated and Catalyzed C-H Bond Amination via Chelation Assistance: Scope, Mechanism and Synthetic Applications

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Chinese Journal of Chemistry 2022年第10期40卷 1204-1223页

作者： Jiao-Li Ma Xu-Ming Zhou Peng-Hu Guo Hui-Cheng Cheng Hong-bing Ji College of Chemistry Guangdong University of Petrochemical TechnologyMaomingGuangdong 525000China Fine Chemical Industry Research Institute School of ChemistrySun Yat-sen UniversityGuangzhouGuangdong 510275China

Nitrogen-containing compounds are ubiquitously found in the fields of organic chemistry,pharmaceuticals,agrochemicals,medicinal chemistry and functional materials.The C-H bond amination reaction is one of the most straightforward protocols in the CN bond formation,showing"step"and"atomic"economy.As a catalyst for C-H amination reaction,copper exhibits its unique catalytic properties due to easily accessible oxidation states.The research progress of copper-catalyzed C-H amination in recent years is summarized.At the same time,reaction mechanisms are also briefly described in representative aminations to provide insights for the development prospects of highly practical and more environmentally benignprocesses.

关键词： copper Chelation assistance CH amination N-Heterocycle synthesis Cross-coupling

Alleviative effects of a novel strain Bacillus coagulans XY2 on copper-induced toxicity in zebrafish larvae

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Journal of Environmental Sciences 2023年第3期125卷 750-760页

作者： Fang Ai Xuedi Huang Yalan Wu Chen Ji Yufang Gao Ting Yu Fujie Yan National Engineering Laboratory of Intelligent Food Technology and Equipment College of Biosystems Engineering and Food ScienceZhejiang UniversityHangzhou 310058China

copper (Cu) is a kind of micronutrient element that is essential for human metabolism.However,it is also considered as an environmental pollutant which is toxic to organisms at a high concentration level.Probiotics,regarded as beneficial microorganisms for promoting human health,have functions of antioxidant capacity,immune-enhancing properties,intestinal barrier protection and regulation.Several studies have reported that probiotics show positive effects on alleviating and intervening heavy metals toxicity.However,evidence for relieving copper-induced toxicity by probiotics is still limited.In this study,we firstly conducted a zebrafish larvae model to screen out microorganisms which are helpful for CuSO_(4)toxicity resistance and one novel strain named as Bacillus coagulans XY2 was discovered with the best protective activity.B.coagulans XY2 significantly reduced the mortality of zebrafish larvae exposed to 10μmol/L CuSO_(4)for 96 hr,as well as alleviated the neutrophils infiltration in the larvae lateral line under a 2 hr exposure.B.coagulans XY2 exhibited a high in vitro antioxidant activity and against CuSO_(4)-induced oxidative stress in zebrafish larvae by up-regulating sod1,gstp1 and cat gene transcriptional levels and relevant enzymatic activities.CuSO_(4)stimulated the inflammation process resulting in obvious increases of gene il-1βand il-10 transcription,which were suppressed by B.coagulans XY2 intervention.Overall,our results underline the bio-function of B.coagulans XY2 on protecting zebrafish larvae from copper toxicity,suggesting the potential application values of probiotics in copper toxicity alleviation on human and the environment.

关键词： copper Probiotics Bacillus coagulans Oxidative stress Inflammation

Dietary intake and serum levels of copper and zinc and risk of hepatocellular carcinoma:A matched case-control study

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Chinese Medical Journal 2024年第5期137卷 596-603页

作者： Xiaozhan Liu Yaojun Zhang Dinuerguli Yishake Yan Luo Zhaoyan Liu Yuming Chen Huilian Zhu Aiping Fang Guangdong Provincial Key Laboratory of Food Nutrition and HealthSchool of Public HealthSun Yat-sen UniversityGuangzhouGuangdong 510080China State Key Laboratory of Oncology in South China Sun Yat-sen University Cancer CenterGuangzhouGuangdong 510060China

Background:copper and zinc are involved in the development of multiple malignancies;yet,epidemiological evidence on hepatocellular carcinoma(HCC)is limited.This study aimed to investigate the association between dietary intake and serum levels of copper and zinc with the risk of HCC.Methods:A total of 434 case-control pairs matched for sex and age(±1 year)were included in this study.Cases with newly diagnosed HCC were from the Guangdong Liver Cancer Cohort(GLCC)study,and healthy controls were from the Guangzhou Nutrition and Health Study(GNHS).A semi-quantitative 79-item food frequency questionnaire(FFQ)was used to assess habitual dietary intakes of copper and zinc.Serum levels of copper and zinc were measured by using inductively coupled plasma mass spectrometry.The copper(Cu)/zinc(Zn)ratio was computed by dividing copper levels by zinc levels.Conditional logistic regression models were performed to calculate the odds ratio(OR)and 95%confidence intervals(CI)for per 1 standard deviation increase(per-SD increase)in copper and zinc levels.Results:Higher dietary intake(OR_(per-SD increase)=0.65,95%CI:0.44,0.96,P_(trend)=0.029)and serum levels of zinc(OR_(per-SD increase)=0.11,95%CI:0.04,0.30,P_(trend)copper levels(OR_(per-SD increase)=2.05,95%CI:1.39,3.03,P_(trend)=0.020)and serum Cu/Zn ratio(OR_(per-SD increase)=6.53,95%CI:2.52,16.92,P_(trend)copper intake and dietary Cu/Zn ratio were not associated with HCC risk.Conclusion:Zinc may be a protective factor for HCC,especially among men,but the effects of copper on HCC risk are not clear.

关键词： copper Zinc Hepatocellular carcinoma risk Case-control studies Dietary intake Serum

Asymmetric Alkynylation of Tertiary Carbon-Centered Radical via copper-Catalyzed Radical Relay

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Chinese Journal of Chemistry 2022年第14期40卷 1699-1704页

作者： Dunqi Wu Lianqian Wu Pinhong Chen Guosheng Liu Chang-Kung Chuang Institute East China Normal University3663 North Zhongshan RoadShanghai 200062China State Key Laboratory of Organometalic Chemistry and Shanghai Hongkong Joint Laboratory in Chemical SynthesisCenter for Excellence in Molecular SynthesisShanghai Institute of Organic ChemistryUniversity of Chinese Academy of SciencesChinese Academy of Sciences345 Lingling RoadShanghai 200032China

Alkynes are frequently found in a high proportion of natural products and bioactive moleculars,as well as a common synthon in organic synthesis,which can be easily transformed to an alkenyl,alkyl,heteroaryl,or carboxylic acid group.The enantioselective construction of alkyne substituted all carbon quaternary stereocenters is rarely reported and still a big challenge.As part of our continuous effort on developing asymmetric radical transformations,we found introducing an amidyl group(CONHAr)adjacent to the tertiary carbon radical could enable the asymmetric radical coupling with alkyne reagents.The amidyl group may stabilize the tertiary carbon radical or coordination with the chiral copper catalyst.Herein,we communicate a copper-catalyzed asymmetric trifluoromethyl-alkynylation ofα-aryl substituted acrylamides,which provides a straightforward and efficient access to chiral quaternary all-carbon centers bearing alkynyl groups in good yields and enantioselectivities.This reaction was also applied for the synthesis of chiral functionalized dipeptide.

关键词： copper Asymmetric catalysis Asymmetric alkynylation Chiral quaternary carbon stereocenters Radicals

A desulphurization strategy for Sonogashira couplings by visible light/copper catalysis

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Organic Chemistry Frontiers 2022年第2期9卷 386-393页

作者： Xuan Li Min Jiang Xiaolong Zhu Xiuyan Song Qirong Deng Jian Lv Daoshan Yang Key Laboratory of Optic-electric Sensing and Analytical Chemistry for Life Science MOECollege of Chemistry and Molecular EngineeringQingdao University of Science and TechnologyQingdao266042P.R.China Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology(Ministry of Education) Department of ChemistryTsinghua UniversityBeijing 100084People’s Republic of China College of Materials Chemistry and Chemical EngineeringHangzhou Normal UniversityHangzhou310036P.R.China

The development of new copper-based catalysts in photoredox transformations has become a rapidly growing area of research and has been actively explored in the past several years.Herein,we have developed a new copper-based catalyst,[(binap)(tpy)Cu]Cl,and applied it in the visible-light promoted Sonogashira coupling reactions.This mild protocol results in various substituted alkynes from simple sulfonium salts which can be easily prepared from commercially available and inexpensive thiols,alcohols,and alkyl halides.This study will broaden the still limited strategies of copper photocatalysts in organic transformations.

关键词： copper visible coupling

Determination of dietary copper requirement by the monoamine oxidase activity in kidney of broilers from 1 to 21 days of age

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Animal Nutrition 2022年第1期8卷 227-234页

作者： Yun Hu Zhiyong Chen Lin Lu Liyang Zhang Tao Liu Xugang Luo Xiudong Liao Poultry Mineral Nutrition Laboratory College of Animal Science and TechnologyYangzhou UniversityYangzhou225000China Mineral Nutrition Research Division State Key Laboratory of Animal NutritionInstitute of Animal ScienceChinese Academy of Agricultural SciencesBeijing100193China Biochemistry Department Case Western Reserve UniversityCleveland44106USA

The current dietary copper(Cu)requirement(8 mg/kg)of broilers is mainly based on growth,hemoglobin concentration,or hematocrit,which might not be the most sensitive indices to evaluate dietary Cu requirements of broilers.The present study was carried out to estimate dietary Cu requirements of broilers fed a conventional corn-soybean meal diet from 1 to 21 d of age using biochemical or molecular biomarkers.A total of 3841-d-old Arbor Acres male broilers were randomly allocated to 1 of 6 treatments with 8 replicates and fed a Cu-unsupplemented corn-soybean meal basal diet containing 5.17 mg Cu/kg by analysis and the basal diet supplemented with 3,6,9,12 or 15 mg Cu/kg as CuSO4,5H2O for 21 d.Regression analysis was performed to estimate the optimal dietary Cu level using the broken-line model.Dietary supplemental Cu level affected(P0.05)on the growth performance,Cu contents in heart,kidney,pancreas and spleen,Cu-and zinc-containing superoxide dismutase(CuZnSOD)activity and ceruloplasmin content in serum,CuZnSOD and cytochrome c oxidase(COX)activities and ceruloplasmin,CuZnSOD,MAO A,MAO B,COX 4I1 and COX 1 mRNA and protein expressions in the above tissues of broilers.As dietary supplemental Cu levels increased,Cu contents in serum and liver increased linearly(P<0.05),but kidney MAO activity decreased linearly and quadratically(P<0.05).The estimated dietary Cu requirement based on the fitted broken-line model(P=0.035)of kidney MAO activity was 11.30 mg/kg.In conclusion,kidney MAO activity is a new and sensitive criterion to evaluate the dietary Cu requirement of broilers,and the dietary Cu requirement was 11.30 mg/kg for broilers fed the conventional corn-soybean meal diet from 1 to 21 d of age,which is higher than the current National Research Council(NRC)Cu requirement(8 mg/kg)of broilers.

关键词： copper Monoamine oxidase Requirement Broilers