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Recent Advances in Deuteration Reactions

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Chinese Journal of Chemistry 2024年第10期42卷 1145-1156页

作者： Hao Li Muhammad Shabbir Wu Li Aiwen Lei Institutefor Advanced Studies(IAS) Collegeof Chemistry and Molecular SciencesWuhan UniversityWuhanHubei 430072China

The deuteration of organic compounds has attracted more attentions in recent years for the potential applications in new drug discovery and synthetic *** this purpose,many efficient deuterium labeling methodologies have been developed,including hydrogen isotope exchange(HIE),reductive deuteration,and dehalogenative deuteration that allow for the synthesis of selectively deuterated *** the last few years,great breakthroughs in selective isotope labeling have been achieved and the interest in new methodologies for the deuteration of organic molecules is *** this review,we summarized the recent developments in the selective deuteration of organic molecules since *** types of key processes in deuterium incorporation reactions,including H/D exchange,reductive deuteration and dehalogenative deuteration,are introduced and discussed.

关键词： Deuterated compounds H/D exchange Reductive deuterations Dehalogenative deuterations Deuterium C-Hactivation Synthetic methods

Provenance of the Lower Jurassic pyroclastic sediments in the Zigui Basin:Implication for crustal thickening in the eastern Qinling orogenic belt

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Science China Earth sciences 2024年第1期67卷 196-207页

作者： Rong CHAI Jianghai YANG Yuansheng DU Chengshan WANG school of Earth sciences and Resources China University of Geosciences(Beijing)Beijing 100023China school of Earth sciences China University of Geosciences(Wuhan)Wuhan 430074China Chinese Academy of Geological sciences Beijing 100037China

The Late Triassic witnessed significant collisional orogenic events in the Qinling orogenic belt,accompanied by magma underplating and tectonic *** processes potentially resulted in substantial crustal thickening and uplift of the Qinling ***,due to the absence of igneous rock records from this period in the eastern section of the Qinling orogen,the changes in crustal thickness during this orogenic process have not been thoroughly investigated.A series of foreland basins emerged during the Early Mesozoic to the south of the East Qinling orogenic *** basins have preserved clastic sedimentary rocks derived from the uplift and erosion of the orogenic *** sedimentary records serve as crucial records to reconstruct the evolutionary history of the Qinling *** further clarify the collisional orogenic process of the Qinling orogenic belt,this study conducted in situ volcanic lithic fragment geochemistry,detrital zircon U-Pb chronology and trace element composition analysis on the sandstones of the Lower Jurassic Tongzhuyuan Formation in the Zigui *** results suggest that the sandstones,which exhibit a significant abundance of volcanic lithic fragments,has a characteristic detrital zircon age group of 250–200 Ma,indicating a major provenance from the Triassic volcanic *** with regional correlation and paleocurrent analysis,the detrital zircon U-Pb age data show that the source area of volcanic rocks should be in the Qinling orogenic belt to the north of the *** interpretation is further supported by the Triassic granitic rocks exposed in the western part of the orogenic belt,representing the magmatism during the Triassic collisional orogenesis in the Qinling *** on the co-varying relationships between present-day crust thickness with the chemical compositions of granite rocks and zircons,the La/Yb ratio of volcanic lithic fragments in the Tongzhuyuan Formation and the Eu/Eu*ratio of detrital zircon

关键词： Qinling orogenic belt Zigui Basin Late Triassic Detrital zircons Crustal thickening

Water–soluble and polarity–sensitive near–infrared fluorescent probe for long–time specific cancer cell membranes imaging and C. Elegans label

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Chinese Chemical Letters 2024年第4期35卷 321-323页

作者： Lixian Fu Yiyun Tan Yue Ding Weixia Qing Yong Wang Henan International Joint Laboratory of Medicinal Plants Utilization College of Chemistry and Molecular SciencesHenan UniversityKaifeng 475004China school of Basic Medical Science Henan UniversityKaifeng 475004China

A novel D–π –A structure and near–infrared fluorescent probe(DCITT) with high polarity sensitivity and membrane targeting was reported. The fluorescent spectra of DCITT were polarity dependent and Stokes shift was greater than 300 nm. Due to its high fluorescence quantum yield, low cytotoxicity and photostability, DCITT could be used as a labeling probe in multicellular organisms. In particular, DCITT effectively distinguished tumor cells from normal cells because it could specifically light up the cancer cells membrane based on strong red fluorescence for a long time. On this basis, a polar–sensitive cell membrane probe is developed to differentiate tumor cells from normal cells, which provides an idea and method for the early diagnosis of tumor at cellular level.

关键词： NIR–fluorescent probe Polarity–sensitive Bioimaging Targeting cell membrane Differentiate tumor and normal cells

Dynamic Crosslinked Phosphorescent Poly(vinyl alcohol)-Terpyridine Films with Enhanced Mechanical Properties and Tunable Shape Memory

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Chinese Journal of Polymer Science 2024年第10期42卷 1595-1601页

作者： Meng Wei Wei-Hao Feng Chen Yu Zhen-Yi Jiang Guang-Qiang Yin Wei Lu Tao Chen Key Laboratory of Advanced Marine Materials Ningbo Institute of Materials Technology and Engineering Chinese Academy of Sciences school of Chemical sciences University of Chinese Academy of Sciences school of Materials Science and Chemical Engineering.Ningbo University

Achieving versatile room temperature phosphorescence （RTP） materials, especially with tunable mechanical properties and shape memory is attractive and essential but rarely reported. Here, a strategy was reported to realize multi-functional RTP films with multicolor fluorescence, ultralong afterglow, adjustable mechanical properties, and shape memory through the synergistic dynamic interaction of lanthanide（LnⅢ）-terpyridine coordination, borate ester bonds, and hydrogen bondings in a poly（vinyl alcohol）(PVA) matrix. By varying the amount of borax,the mechanical properties of the films could be finely controlled due to the change of crosslinking degree of dynamic borate ester bonds in *** assembly and disassembly of borate ester bonds upon the trigger of borax and acid were applied as reversible linkage to achieve programmable shape memory behavior. In addition, the films displayed both fascinating multicolor fluorescence and ultralong afterglow characteristics due to the presence of Ln III doping and confinement of terpyridine in PVA. This study provides a new avenue to impart modulable mechanical strength and shape memory to RTP materials.

关键词： Dynamic bonds Multicolor fluorescent Room temperature phosphorescence materials Shape memory Tunable mechanical properties

Competitive intermetallics formation in Pd-Zn-Cd system via seeded growth from ultra-thin Pd nanosheets for electrocatalytic ethanol oxidation reaction

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Nano Research 2024年第9期17卷 8552-8559页

作者： Donghao Zhang Lianxi Si Qianqian Ren Xintong Yan Shi Hu Department of Chemistry School of ScienceTianjin Key Laboratory of Molecular Optoelectronic ScienceTianjin UniversityTianjin 300072China

Pd-based catalysts exhibit higher catalytic activity and durability in many electrochemical ***,the electrochemical performance can be further enhanced by fine-tune of the alloy *** binary alloys have been fully studied,the multicomponent alloys are far beyond understanding,which leaves cocktail effect a compromised explanation for the high-entropy *** Pd nanosheet-seeded growth was used to synthesize a Pd-Zn-Cd ternary alloy by accurately controlling the Pd-Zn-Cd molar ratio through adjusting the amount of introduced Cd *** analysis of the crystal phase structure of PdCdZnx and PdZn_(x)Cd_(1-x),the competitive relationship of Zn and Cd in the alloying process with Pd was unveiled:Pd1Cd1 intermetallics(IMC)is thermodynamically favored over Pd_(1)Zn_(1)IMC in the ternary ***,the increased structure stability of PdCd over PdZn does not bring about increased durability in the catalytic ethanol oxidation *** morphology selection of Pd seeds is also crucial for the study,as Pd cubes,Pd tetrahedrons,and Pd octahedrons do not form PdZn in the same *** successful alloying through the seeded growth depends on the maximum diffusion depth of foreign atoms into the seed.

关键词： PdZn alloy seed growth method ethanol oxidation reaction composition control ternary alloying

Partial regularity and nonlinear potential estimates for Stokes systems with super-quadratic growth

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Science China Mathematics 2024年第7期67卷 1525-1554页

作者： Lingwei Ma Zhenqiu Zhang school of Mathematical sciences Tianjin Normal UniversityTianjin300387China school of Mathematical sciences and LPMC Nankai UniversityTianjin300071China

This paper builds a bridge between partial regularity theory and nonlinear potential theory for the following generalized stationary Stokes system with super-quadratic growth and continuous coefficients:-div A(x,Du)+■π=f,div u=0,where Du is the symmetric part of the gradient■*** first establish anε-regularity criterion involving both the excess functional of the symmetric gradient Du and Wolff potentials of the nonhomogeneous term f to guarantee the local vanishing mean oscillation(VMO)-regularity of Du in an open subset Ω_(u) of Ω with full *** anε-regularity criterion leads to a pointwise Wolff potential estimate of Du,which immediately infers that Du is partially C^(0)-regular under appropriate ***,we give a local continuous modulus estimate of Du.

关键词： nonlinear Stokes system partial regularity Wolff potential estimates continuous modulus estimates

Pyruvate kinase M in germ cells is essential for sperm motility and male fertility but not spermatogenesis

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Asian Journal of Andrology 2024年第2期26卷 212-219页

作者： Gao-Qing Qian Xiao-Chen Wang Xi Zhang Bin Shen Qiang Liu State Key Laboratory of Reproductive Medicine and Offspring Health Nanjing Medical UniversityNanjing 211166China Shanghai Key Laboratory of Reproductive Medicine Department of HistoembryologyGenetics and Developmental BiologyShanghai Jiao Tong University School of MedicineShanghai 200025China State Key Laboratory of molecular Biology Shanghai Key Laboratory of Molecular AndrologyShanghai Institute of Biochemistry and Cell BiologyCenter for Excellence in Molecular Cell ScienceChinese Academy of SciencesUniversity of Chinese Academy of SciencesShanghai 200031China

Male germ cells employ specific metabolic pathways throughout their developmental *** a previous study,we discovered heightened expression of pyruvate kinase M(PKM),a pivotal glycolytic enzyme,in spermatogonia and *** gain deeper insights into PKM's roles in spermatogenesis,sperm function,and male fertility,we engineered a conditional-knockout mouse model(Pkm-vkO mice)to selectively disrupt the Pkm gene within germ *** maintaining regular testicular histology and sperm morphology,the male Pkm-vko mice were infertility,characterized by significant impairments in sperm motility and adenosine triphosphate(ATP)*** addition,Pkm-null spermatozoa exhibited similar deficits in protein tyrosine phosphorylation linked to capacitation,as well as compromised performance in in vitro fertilization *** conclude,PKM's presence is not obligatory for the entirety of spermatogenesis in male germ cells;however,it emerges as a critical factor influencing sperm motility and overall male fertility.

关键词： glycolysis male fertility pyruvate kinase M sperm motility spermatogenesis

Ailanthone ameliorates pulmonary fibrosis by suppressing JUN-dependent MEOX1 activation

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Acta Pharmaceutica Sinica B 2024年第8期14卷 3543-3560页

作者： Lixin Zhao Yuguang Zhu Hua Tao Xiying Chen Feng Yin Yingyi Zhang Jianfeng Qin Yongyin Huang Bikun Cai Yonghao Lin Jiaxiang Wu Yu Zhang Lu Liang Ao Shen Xi-Yong Yu The Fifth Affiliated Hospital Guangzhou Municipal and Guangdong Provincial Key Laboratory of Molecular Target and Clinical PharmacologyNMPA&State Key LaboratorySchool of Pharmaceutical SciencesGuangzhou Medical UniversityGuangzhou 511436China

Pulmonary fibrosis poses a significant health threat with very limited therapeutic options *** this study,we reported the enhanced expression of mesenchymal homobox 1(MEOX1)in pulmonary fibrosis patients,especially in their fibroblasts and endothelial cells,and confirmed MEOX1 as a central orchestrator in the activation of profibrotic *** high-throughput screening,we identified Ailanthone(AIL)from a natural compound library as the first small molecule capable of directly targeting and suppressing *** demonstrated the ability to inhibit both the activation of fibroblasts and endothelial-to-mesenchymal transition of endothelial cells when challenged by transforming growth factor-b1(TGF-b1).In an animal model of bleomycin-induced pulmonary fibrosis,AIL effectively mitigated the fibrotic process and restored respiratory ***,AIL acted as a suppressor of MEOX1 by disrupting the interaction between the transcription factor JUN and the promoter of MEOX1,thereby inhibiting MEOX1 expression and *** summary,our findings pinpointed MEOX1 as a cell-specific and clinically translatable target in ***,we demonstrated the potent anti-fibrotic effect of AIL in pulmonary fibrosis,specifically through the suppression of JUN-dependent MEOX1 activation.

关键词： Ailanthone MEOX1 Pulmonary fibrosis JUN TGF-b1 High-throughput screening Natural product

High-Performanceα-Diimine Nickel Complexes for Facile Access of PE Elastomers with Exceptional Material Properties

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Chinese Journal of Polymer Science 2024年第5期42卷 620-635,I0008页

作者： Li-Dong Qin Xin-Yu Wang Qaiser Mahmood Zhi-Xin Yu Yi-Zhou Wang Song Zou Tong-Ling Liang Wen-Hua Sun school of Pharmaceutical sciences Changchun University of Chinese MedicineChangchun130117China Chemistry and Chemical Engineering Guangdong Laboratory Shantou515031China Key Laboratory of Engineering Plastics and Beijing National Laboratory for molecular Science Institute of ChemistryChinese Academy of SciencesBeijing100190China

For practicable elastomeric polyethylene,achieving high catalyst thermal stability and activity,along with precise control of polymer properties such as branching density,molecular weights,and distribution,is crucial but *** this study,two sets of symmetricalα-diimine nickel complexes,each comprising four nickel bromide or chloride complexes,were synthesized and investigated their performance for ethylene polymerization under various reaction *** activation with either Et2AlCl or MMAO cocatalysts,these complexes displayed not only high activity but also generated high molecular weight polyethylenes with controlled polydispersity and a substantial number of *** catalyst with the least steric hindrance displayed the remarkable high activity(up to 1.2×10^(7) g·mol^(-1)·h^(-1)).Notably,nickel bromides demonstrated higher activity compared to their chloride *** investigation into the effect of reaction temperature on catalytic performance revealed that NiBrMe-MMAO system displayed high thermal stability(activity up to 2.51×10^(6) g·mol^(-1)·h^(-1) at 100℃)and consistently yielded high polymer molecular weights with narrow polydispersity over a broad temperature range of 30-100℃.Of significant note,mechanical analysis of the resulting polyethylene demonstrated excellent ultimate tensile strength and high strain at ***,the polyethylene sample prepared at 100℃exhibited ultimate tensile strength up to 10 MPa with 1863%maximum strain at break and a strain recovery of up to 54.9%after ten cycles at a fixed strain of 300%,indicating excellent material properties of prepared thermoplastic polyethylene elastomers(TPE).

关键词： Thermoplastic polyethylene elastomers α-Diimine nickel pre-catalysts Ethylene polymerization Mechanical properties Highly branched polyethylene