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China Petroleum Processing & Petrochemical Technology 2024年第2期26卷 46-56页

作者： Qiu Shiming Wang Shengjie School of Chemistry and Chemical Engineering Guangxi Minzu Normal UniversityChongzuo 532200GuangxiChina Guangxi Key Laboratory for High-value Utilization of Manganese Resources Chongzuo 532200GuangxiChina

The Cu/ZnO catalyst formed upon the calcination of aurichalcite has a uniform distribution of ZnO,which can delay the sintering of Cu species at high temperatures.In this study,aurichalcite possessing a nearly pure phase was prepared using the ammonium complex dissociation precipitation method,and the effect of calcination temperature on the structure and surface properties of the derived Cu/ZnO catalyst was studied.The results show that the calcination temperature determines the particle size and crystallization degree of the Cu/ZnO catalyst and the surface properties of the corresponding copper oxide and reduced copper.Low-temperature calcination is more conducive to reducing the particle size of the Cu/ZnO catalyst,increasing the specific surface area,and generating abundant defect characteristics on the surface,which is key to obtaining highly dispersed copper and copper-specific surface area catalysts by subsequent reduction.Additionally,the Cu/ZnO catalyst derived using a 300℃or 400℃calcination proved to have a higher specific activity per gram of copper than a commercial Cu/Zn/Al catalyst.The discovery in this study opens up a new method for the convenient preparation of a high-temperature resistant Cu/Zn methanol reforming catalyst.

关键词： methanol reforming copper zinc oxide lattice defect

copper homeostasis dysregulation promoting cell damage and the association with liver diseases

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Chinese Medical Journal 2023年第14期136卷 1653-1662页

作者： Tao Liu Yali Liu Feiyu Zhang Yanhang Gao Department of Hepatology The First Hospital of Jilin UniversityJilin UniversityChangchunJilin 130021China

copper plays an important role in many metabolic activities in the human body.copper level in the human body is in a state of dynamic equilibrium.Recent research on copper metabolism has revealed that copper dyshomeostasis can cause cell damage and induce or aggravate some diseases by affecting oxidative stress,proteasome,cuprotosis,and angiogenesis.The liver plays a central role in copper metabolism in the human body.Research conducted in recent years has unraveled the relationship between copper homeostasis and liver diseases.In this paper,we review the available evidence of the mechanism by which copper dyshomeostasis promotes cell damage and the development of liver diseases,and identify the future research priorities.

关键词： copper Liver disease Cell death Cuproptosis

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 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

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氧化加成形成稳定的Cu(Ⅲ)络合物

Science Bulletin 2024年第3期69卷 288-289页

作者：殷凌峰刘巍 Department of Chemistry University of CincinnatiCincinnati OH 45221USA

Organic chemists now have a much better understanding of the mechanism of copper catalysis,thank to the recent work by Shen,Hartwig,and Xue published in Science [1].In this work,Shen’s team demonstrated,that well-defined,isolable organocopper(Ⅲ) complexes can be synthesized through the oxidative addition of alkyl electrophiles to copper(1) species.This elemental step has been widely proposed as a key step in copper-catalyzed cross-coupling of alkyl electrophiles (Fig.1).

关键词： copper 氧化加成 oxidative

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

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

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

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

Different copper sources and levels affect growth performance,copper content,carcass characteristics,intestinal microorganism and metabolism of finishing pigs

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Animal Nutrition 2022年第1期8卷 321-330页

作者： Yang Wen Runxian Li Xiangshu Piao Gang Lin Pingli He State Key Laboratory of Animal Nutrition College of Animal Science and TechnologyChina Agricultural UniversityBeijing 100193China Institute of Quality Standards and Testing Technology for Agricultural Products Chinese Academy of Agricultural ScienceKey Laboratory of Agrifood Safety and QualityMinistry of AgricultureBeijing 100081China

copper(Cu)is an essential trace element in the production of swine.This study was conducted to investigate the effect of 3 different sources of Cu on growth performance,Cu metabolism,and intestinal microorganisms of finishing pigs,so as to estimate the bioavailability of the 3 sources for pigs.A total of 42 male finishing pigs(88.74±5.74 kg)were randomly allocated to 7 treatments.The factors were 3 sources(CuSO4,Cu-glycine,Cu-proteinate)and 2 levels(5 and 20 mg/kg)of Cu,plus one negative control treatment(0 mg/kg added Cu level)for the entire 28-d experiment.The average daily gain(ADG)and feed to gain ratio(F:G)both increased when Cu was added.The Cu level in liver,bile,kidney,serum,lung,urine and feces rose(Pcopper uptake protein 1(CTR1)and export transporter ATPase copper transporting alpha(ATP7A)in supplemental Cu treatments were down-regulated compared to the control.Also,peptide transporter 1(PepT1)and lanine-serine-cysteine transporter,type-2(ASCT2)were significantly(P<0.01)up-regulated in 20 mg/kg Cu-proteinate and Cu-glycinate treatments,respectively.Microbial diversity was lowest in the 20 mg/kg CuSO4 treatment,and the ratio of Firmicutes to Bacteroidetes was higher in added Cu treatments,especially Cu-glycinate treatment.These results indicate that uptake of different Cu forms is facilitated by different transporters and transport mechanisms,and compared with inorganic Cu,organic Cu provides benefits to intestinal microflora and reduces Cu excretion.

关键词： copper Metabolism Residues Microflora community Finishing pig