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Nano Research 2024年第7期17卷 5914-5921页

作者： chun-ying chen Qi-Jie Mo Fu-Zhen Li Hai-Li Song Li Zhang MOE Laboratory of Bioinorganic and Synthetic Chemistry Lehn Institute of Functional MaterialsSchool of ChemistrySun Yat-Sen UniversityGuangzhou 510006China

Alkene hydrosilylation is one of the most concise and atom-economical methods to synthesize organosilicon ***,we reported the precise immobilization of metal single atoms(M-SAs;M=Ru,Rh,Ir,Pd,Pt,and Au)into a porphyrinic metalorganic framework(MOF)of PCN-222(PCN=porous coordination network),and then applied the resultant MOF composites of M-SAs@PCN-222 to alkene *** solvent-free conditions,Pt-SAs@PCN-222 displayed an especially high catalytic efficiency with the turnover frequency up to 119 s−1 and the maximum turnover number of 906,250 at room *** and theoretical studies revealed that there existed strong interactions between Pt-SAs@PCN-222 and the substrates,which helped to condense the substrates in the cavities of the porous *** density functional theory calculations and molecular dynamics simulations disclosed that PCN-222 could transfer electrons to Pt-SAs to enhance the silane oxidative addition and drive the reaction to proceed smoothly via Chalk–Harrod pathway.

关键词： alkene hydrosilylation single atom catalysts metal-organic frameworks precision chemistry synergistic catalysis

Intervention control of aerobic exercise in maintaining quality of life and pulmonary hypertension in hemodialysis patients

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World Journal of Clinical Cases 2024年第20期12卷 4217-4229页

作者： Dan-Dan Wang Min cheng chun-ying chen Department of Rehabilitation Medicine Zhejiang HospitalHangzhou 310012Zhejiang ProvinceChina Blood Purification Center Zhejiang HospitalHangzhou 310012Zhejiang ProvinceChina

BACKGROUND Pulmonary hypertension is a serious complication in the treatment of maintenance hemodialysis patients,which seriously affects the quality of life of patients and threatens their life ***,treatment and improvement of pulmonary hypertension are of great significance to improve the quality of life of *** To investigate the intervention and control of pedal-powered bicycle in maintaining quality of life and pulmonary hypertension in hemodialysis *** 73 patients with maintenance hemadialysis combined with pulmonary arterial hypertension at a hemodialysis center in a certain hospital from May 2021 to May 2022 are *** are divided into two groups,37 cases in the control group(group C)and 36 cases in the intervention group(group I).Patients are divided into two groups,group C is treated with oral administration of betaglandin sodium combined with routine nursing *** on group C,group I conducts power cycling *** After treatment,group I patients had higher muscle strength,36-Item Short Form Health Survey scores,and Kidney Disease Targets Areas scores;The 6-minute walk distance test index level was higher and the Borg score was lower;The group I had lower systolic blood pressure,greater vital capacity,higher positive emotion,lower systolic pulmonary artery pressure index level,higher arterial partial oxygen pressure level,lower pulmonary vascular resistance index level,and higher blood oxygen saturation level[158.91±11.89 vs 152.56±12.81,1795.01±603.18 vs 1907.20±574.15,24.00(22.00,29.00)vs 24.00(22.00,28.00),P<0.001].CONCLUSION Aerobic exercise combined with Western medicine treatment can effectively improve patients'pulmonary hypertension,alleviate their negative emotions,and enable them to achieve a higher level of quality of life.

关键词： Aerobic exercise Hemodialysis Pulmonary arterial hypertension Cycle ergometer Quality of life

New Amines and Activation Modes in Asymmetric Aminocatalysis

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Chinese Journal of Chemistry 2021年第7期39卷 1775-1786页

作者： Zhi-Chao chen Wei Du ying-chun chen Key Laboratory of Drug-Targeting and Drug Delivery System of the Ministry of Education and Sichuan Research Center for Drug Precision Industrial Technology West China School of PharmacySichuan UniversityChengdu 610041China College of Pharmacy Third Military Medical UniversityShapingbaChongqing 400038China

Asymmetric aminocatalysis has become one of the most powerful strategies for the transformations of carbonyl substances over the past two ***,we describe the research from our laboratory that significantly expands the horizon of *** includes the development and application of cinchona-based primary amines,fruitful reactions based on HOMO-raising strategy,and the disclosure of amine/thiol double activation catalysis.

关键词： Organocatalysis Aminocatalysis Amine/thiol double catalysis Cycloaddition Domino reactions

Construction of polycyclic spirooxindoles through[3+2]annulations of Morita–Baylis–Hillman carbonates and 3-nitro-7-azaindoles

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Chinese Chemical Letters 2017年第3期28卷 512-516页

作者： Kai-Kai Wang Wei Du Jin Zhu ying-chun chen chengdu Institute of Organic Chemistry Chinese Academy of Sciences Chengdu 610041 China Key Laboratory of Drug-Targeting and Drug Delivery System of the Ministry of Education West China School of Pharmacy Sichuan University Chengdu 610041 China University of Chinese Academy of Sciences Beijing 100049 China

A mild and efficient dearomatic [3＋2] annulation reaction of 3-nitro-7-azaindoles and Morita Baylis Hillman carbonates from isatins was developed catalyzed by DMAP, affording the corresponding polycyclic spirooxindoles containing fused azaindoline architectures and vicinal quaternary centers in excellent yields（up to 96%） with high regio- and diastereoselectivity（dr 〉 19：1）. Moderate enantioselectivity（79% ee） was obtained by employing a chiral DMAP-type Lewis base catalyst.

关键词： Morita–Baylis–Hillman carbonates [3+2] annulation Spirooxindoles Regioselectivity Dearomatization

Solvent-Regulated Diastereodivergent [3+2] Annulations of CF_(3)-Containing Morita-Baylis-Hillman Carbonates with Cyclic Sulfonimines

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Chinese Journal of Chemistry 2022年第10期40卷 1185-1189页

作者： Bao-xin Liu Ru-Jie Yan Wei Du ying-chun chen Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry and Sichuan Province and Sichuan Research Center for Drug Precision Industrial TechnologyWest China School of PharmacySichuan UniversityChengduSichuan 610041China College of Pharmacy Third Military Medical UniversityShapingbaChongqing 400038China

A solvent-regulated diastereodivergent[3+2]annulation reaction between Morita-Baylis-Hillman carbonates from aryl trifluoromethyl ketones and cyclic sulfonimines is developed under the catalysis of a modified cinchona alkaloid,furnishing diverse polycyclic products bearing vicinal quaternary stereogenic centers with outstanding enantioselectivity and moderate to high diastereoselectivity.

关键词： Diastereodivergent synthesis [3+2]annulation Trifluoromethyl group Lewis bases Solvent effects

Natural aging mechanism of buried polyethylene pipelines during long-term service

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Petroleum Science 2023年第5期20卷 3143-3156页

作者： ying-chun chen Yan-Feng Li Yan Xi Qiang Li Qi Lu Jie Yang Beijing University of Technology Beijing100124China Xinjiang Inspection Institute of Special Equipment Urumqi830011XinjiangChina

Currently,accelerated aging tests are widely used to study the aging process of polyethylene ***,this approach can only simulate one or several main influencing factors in the natural environment,which are often quite different from the actual environment of the buried *** this study,five types of PE80 buried pipelines in service for 9e18 years were taken as the research object,while new PE80 pipelines were taken as the reference *** aging process and mechanism of polyethylene buried pipelines were studied through mechanical and chemical property tests and microstructural *** results showed that the pipeline exhibited cross-linking as the main aging mechanism after being in service for 0e18 *** aging degree and law of the inner and outer surface of the pipeline were compared,and the observed mechanism of both surfaces was *** 18 years in service,the elongation at the break of the pipe decreased by 16.2%,and the toughness of the matrix in the main collapse area of the tensile sample was the fundamental reason responsible for changes in the mechanical ***,after 18 years in service,the oxidation induction time of the pipeline was 25.7 min,which was 28.5% higher than the national standard *** were no potential safety hazards during continuous long-term *** results of this paper provide reference data and theoretical guidance for the aging process study of buried polyethylene pipelines.

关键词： Polyethylene Buried pipelines Long-term service Natural aging

Phosphine-Catalyzed Interrupted Morita-Baylis-Hillman Reaction and Switchable Domino Reactions of a-Substituted Activated Olefins with Formaldehyde and Mechanism Elucidation

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Chinese Journal of Chemistry 2019年第2期37卷 155-160页

作者： Jing Gu Ben-Xian Xiao Qin Ouyang Wei Du ying-chun chen Key Laboratory of Drug-Targeting and Drug Delivery System of the Ministry of Education and Sichuan Research Center for Drug Precision Industrial Technology West China School of PharmacySichuan UniversityChengdu 610041China College of Pharmacy Third Military Medical UniversityShapingbaChongqing 400038China

Summary of main observation and conclusion 3-Olefinic oxindoles can undergo interrupted Morita-Baylis-Hillman reaction with formaldehyde. Apart from the previous reported dephosphoration to access reductive aldol-type products, here we uncovered that completely different pathways were followed by tuning the substitutions of 3-olefinic oxin doles. In com bin ation with formalin, an unexpected domino phosphorus-ylide formation, aldol-type addition, hemeacetal formation and O-substitution process was observed to produce 1,3-dioxolane derivatives. Moreover, a switchable sequence to produce formate derivatives via a key hydride transfer process was furnished by simply replacing formalin with paraformaldehyde. Density functional theory calculations were conducted to well elucidate the catalytic reaction mechanism.

关键词： Phosphine-Catalyzed Interrupted Morita-Baylis-Hillman Reaction Switchable Domino Reactions of a-Substituted Activated Olefins Formaldehyde Mechanism Elucidation

A Mutation of OSOTP 51 Leads to Impairment of Photosystem I Complex Assembly and Serious Photo-damage in Rice

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Journal of Integrative Plant Biology 2012年第2期54卷 87-98页

作者： Jian-Wei Ye Zi-ying Gong chun-Guang chen Hua-Ling Mi Gen-Yun chen National Key Laboratory of Plant Molecular Genetics Institute of Plant Physiology and Ecology Shanghai Institutes for Biological SciencesChinese Academy of Sciences Shanghai 200032 China

Gene expression in chloroplasts is regulated by many nuclear-encoded proteins. In this study, we isolated a rice （Oryza sativa subsp, japonica） mutant osotp51 with significant reduction in photosystem I （PSI）. The osotp51 is extremely sensitive to light and accumulates a higher level of reactive oxygen species. Its leaves are almost albino when grown at 40 ~mol photons/m2 per s. However, grown at 4 umol photons/m2 per s, osotp51 has a similar phenotype to the wild-type. 77K chlorophyll fluorescence analysis showed a blue shift in the highest peak emission from PSI in osotp51. In addition, the level of PSI and PSII dimer is dramatically reduced in osotp51. OSOTP 51 encodes a pentatricopeptide repeats protein, homologous to organelle transcript processing 51 in Arabidopsis. Loss-of-function OSOTP51 affects intron splicing of a number of plastid genes, particularly the ycf3 coding a protein involved in the assembly of PSI complex. OSOTP51 is functionally conserved in higher plants. The mutation of osotp51 indirectly leads to a widespread change in the structure and functions of PSI, results in severe photoinhibition, and finally dies, even when grown under very low light intensity.

关键词： Chloroplast photoprotection photosynthesis splicing ycf3

Palladium-catalysed diastereodivergent inverse- electron-demand oxa-Diels–Alder reactions of in situ formed cyclopentadienones via ligand- control

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Organic Chemistry Frontiers 2022年第5期9卷 1364-1369页

作者： Xing-Xing Yang Xing-Liang Zhao Qin Ouyang Wei Du ying-chun chen Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry and Sichuan Province and Sichuan Research Center for Drug Precision Industrial TechnologyWest China School of PharmacySichuan UniversityChengdu 610041China College of Pharmacy Third Military Medical UniversityShapingbaChongqing 400038China

Here we report Pd(0)-catalysed asymmetric inverse-electron-demand oxa-Diels–Alder reactions between the carbonates of 4-hydroxy-2-cyclopentenones andα-cyano chalcones by in situ generating η^(2)-Pd(0)-cyclopentadienone complexes as HOMO-raised dienophiles,and diastereodivergent synthesis could be realised by employing a bifunctional monophosphine ligand from a chiral aminoalcohol or a proline-derived bisphosphine ligand.

关键词： inverse Palladium stereo

Synthesis and Cytotoxic Activity of Novel Water-soluble Prodrugs of Combretastatin A-4

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Chinese Chemical Letters 2006年第1期17卷 23-26页

作者： Zhi Quart YONG Xiao Ping XU ying chun chen Xu BAO Ling Ling WENG Hu ZHENG Department of Medicinal Chemistry West China School of Pharmacy Sichuan University Chengdu 610041

Novel water-soluble prodrugs of combretastatin A-4 （5-8） were synthesized and evaluated for their in vitro cytotoxicity against lung carcinoma A549. Compound 5, bearing phosphoryl choline （PC） moiety, showed 90% inhibition at 32 ktg/mL concentration after 24 h. The findings showed the PC derivative would be a promising candidate for the development of new water-soluble prodrug of cytotoxic combretastatin A-4,

关键词： Combretastafin A-4 cytotoxicity phosphoryl choline water-soluble prodrug.