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Stabilization and detection of labile reaction intermediates in supramolecular containers

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Chinese Chemical Letters 2024年第6期35卷 47-52页

作者： Rui Wang Yang Liang Julius Rebek Jr. Yang Yu Center for Supramolecular chemistry&Catalysis and Department of chemistry College of ScienceShanghai UniversityShanghai 200444China Skaggs institute for Chemical Biology and Department of chemistry The Scripps Research InstituteLa JollaCA 92037United States

Detection and observation of reactive intermediates is an essential step in investigation of reaction ***,most reactive intermediates are unstable and present at low concentrations;their short lifetimes make them difficult to detect and *** containers offer opportunities for the stabilization and characterization of those labile species,through isolation from the media and protection inside the cavity of the *** this review,we summarize the examples of labile reaction intermediates that are stabilized and characterized with the help of supramolecular *** container compounds include carcerands,deep cavitands and amide *** focus on unstable guest species-cyclobutadiene,benzocyclopropenone,o-benzyne,1,2,4,6-cycloheptatetraene,anti-Bredt's olefin,fluorophenoxycarbene,O-acylisoamide,and hemiaminalthat act as intermediates in certain organic reactions.

关键词： Supramolecular containers Reaction intermediates Labile species stabilization Short-lived species detection Supramolecular chemistry

Photocatalyzed ditrifluoromethylthiolation of alkenes with CF_(3)SO_(2)Na

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Science China chemistry 2024年第2期67卷 587-594页

作者： Fangming Chen Lvqi Jiang Chunyang Hu Jie Liu Wenbin Yi School of chemistry and Chemical Engineering Nanjing University of Science and TechnologyNanjing210094China Key Laboratory of Organofluorine chemistry Shanghai Institute Organic ChemistryChinese Academy of SciencesShanghai200032China

Since the first report of sodium trifluoromethanesulfinate(CF_(3)SO_(2)Na) as an electrophilic trifluoromethylthiolation reagent in 2015,there has been no breakthrough in research in this ***,we disclose an unprecedented usage of CF_(3)SO_(2)Na as a radical trifluoromethylthiolation reagent.A photocatalyzed ditrifluoromethylthiolation of alkenes with CF_(3)SO_(2)Na in the presence of PPh_(3) and catalytic copper has been ***,either Ir[(p-Fppy)_(2)(bpy)]PF_6 or Ir(ppy)_(3) could facilitate this *** studies indicate that initiation of the radical chain proceeded via two different photocatalytic quenching *** protocol provides a practical method for the construction of diverse vicinal ditrifluoromethylthiolated compounds.

关键词： trifluoromethylthiolation photocatalysis radical difunctionalization alkenes

Combining cisplatin and a STING agonist into one molecule for metalloimmunotherapy of cancer

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National Science Review 2024年第1期11卷 107-119页

作者： Shuren Zhang Dongfan Song Wenhao Yu Ji Li Xiaoyu Wang Yachao Li Zihan Zhao Qi Xue Jing Zhao Jie P.Li Zijian Guo State Key Laboratory of Coordination chemistry School of Chemistry and Chemical EngineeringChemistry and Biomedicine Innovation Center (ChemBIC) Nanjing University Department of Urology Afflliated Drum Tower HospitalMedical SchoolNanjing University Nanchuang (Jiangsu)institute of chemistry and Health

Mounting evidence suggests that strategies combining DNA-damaging agents and stimulator of interferon genes(STING) agonists are promising cancer therapeutic regimens because they can amplify STING activation and remodel the immunosuppressive tumor microenvironment. However, a single molecular entity comprising both agents has not yet been developed. Herein, we designed two PtIV-MSA-2 conjugates(Ⅰand Ⅱ) containing the DNA-damaging chemotherapeutic drug cisplatin and the innate immuneactivating STING agonist MSA-2; these conjugates showed great potential as multispecific small-molecule drugs against pancreatic cancer. Mechanistic studies revealed that conjugate Ⅰ upregulated the expression of transcripts associated with innate immunity and metabolism in cancer cells, significantly differing from cisplatin and MSA-2. An analysis of the tumor microenvironment demonstrated that conjugate I could enhance the infiltration of natural killer(NK) cells into tumors and promote the activation of T cells, NK cells and dendritic cells in tumor tissues. These findings indicated that conjugate I, which was created by incorporating a Pt chemotherapeutic drug and STING agonist into one molecule, is a promising and potent anticancer drug candidate, opening new avenues for small-molecule-based cancer metalloimmunotherapy.

关键词： platinum drug STING agonist single-molecule multitarget metalloimmunology

Polyoxometalate-based flexible conductive materials with superionic conductivity

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Science China chemistry 2024年第10期67卷 3299-3309页

作者： Yuxin Wang Shuping Xue Jun Geng Ying Lu Teng Li Xiaozheng Duan Xue Bai Yanli Yang Jingqi Yang Shuxia Liu Key Laboratory of Polyoxometalate and Reticular Material chemistry of Ministry of Education College of ChemistryNortheast Normal University State Key Laboratory of Polymer Physics and chemistry Changchun Institute of Applied ChemistryChinese Academy of Sciences

Flexible ion-conductive materials exhibit intriguing advantages for applications in flexible electronic ***,the further enhancement of their conductivity within environmental limitations is an urgent demand for the development of flexible electronic devices,yet remains as a great ***,we report a“dual-acid”strategy,via the encapsulation of two acids,H3PW12O40（HPW） and NH2SO3H（SA）,with synergistic interaction into poly（vinyl alcohol）-glycerol（PVA-Gly） hydrogel,to achieve polyoxometalate（POM）-based flexible materials with superionic conductivity under various environmental *** a representative example,the prepared PVA-Gly/HPW-SA-20% hydrogel presents an ultrahigh proton conductivity ranging from -30℃(3.33×10-2S cm-1) to room temperature(2.78×10-1S cm-1) under ambient ***,the PVA-Gly/HPW-SA-20% hydrogel exhibits remarkable advantages in anti-freezing,mechanical flexibility and self-adhesiveness,making it a promising multifunctional electrolyte for flexible electronic *** experimental results and molecular dynamics（MD） simulations jointly demonstrate that SA bridges HPW clusters to form a dense proton transport pathway induced by multiple electrostatic and hydrogen bonding interactions between SA and HPW counterparts,which contributes to the high-level proton conductivity of the PVA-Gly/HPW-SA-20% *** work provides new insights into the design of POM-based flexible materials with superionic conductivity.

关键词： polyoxometalates proton conduction dual-acid effect hydrogel molecular dynamics simulation

Making topological protein links using enzymatic reactions

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National Science Review 2024年第03期11卷 50-51页

作者： Roger Castells-Graells Todd O.Yeates Department of chemistry and Biochemistry University of California UCLA-DOE institute for Genomics and Proteomics

Proteins are exceedingly complex molecules though, at their heart, they are essentially linear polymers. Pull at their ends and one obtains an extended backbone. While that is true in most cases, some natural proteins... 详细信息

关键词： DESIGN

Introducing urea into tirapazamine derivatives to enhance anticancer therapy

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National Science Review 2024年第4期11卷 245-253页

作者： Yajun Xu Jianlin Lv Chaoying Kong Ya Liu Kun Wang Zhaohui Tang Xuesi Chen Key Laboratory of Polymer Ecomaterials Changchun Institute of Applied ChemistryChinese Academy of Sciences School of Applied chemistry and Engineering University of Science and Technology of China

Tirapazamine（TPZ） has been approved for multiple clinical trials relying on its excellent anticancer ***,as a typical hypoxia-activated prodrug（HAP）,TPZ did not exhibit survival advantages in Phase Ⅲ clinical trials when used in combination therapy due to the insufficient hypoxia levels in patients' *** this study,to improve the therapeutic effects of TPZ,we first introduced urea to synthesize a series of urea-containing derivatives of *** urea-containing TPZ derivatives showed increased hypoxic cytotoxicity（9.51-30.85-fold） compared with TPZ,while maintaining hypoxic ***,one of these derivatives,showed 20-fold higher cytotoxicity than TPZ while maintaining a similar hypoxic cytotoxicity *** highly efficiently deliver TPZP to the tumors and reduce its side effects on healthy tissues,we further prepared TPZP into a nanodrug with fibrin-targeting ability:***4-NPs,a vascular disrupting agent,was used to increase the fibrin level within tumors and exacerbate tumor *** being combined with CA4-NPs,FT11-TPZP-NPs can accumulate in the hypoxia-aggravated tumors and activate sufficiently to kill tumor *** a single-dose treatment,FT11-TPZP-NPs+CA4-NPs showed a high inhibition rate of 98.1% against CT26 tumor models with an initial volume of ～480 mm3and four out of six tumors were completely eliminated;it thereby exerted a significant antitumor *** study provides a new strategy for improving the therapeutic effect of TPZ and other HAPs in anticancer therapy.

关键词： tirapazamine vascular disrupting agent hypoxia-activated prodrug combretastatin A4 urea

Exfoliation,functionalization and antibacterial activity of transition metal dichalcogenides

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Tungsten 2024年第1期6卷 1-16页

作者： Avijit Mondal Mrinmoy De Department of Organic chemistry Indian Institute of ScienceBengaluru 560012India

Due to the growing resistance of available drugs to bacterial infection and the slow development of antibiotics,there is a continuous need to design and develop new antibacterial *** interest to develop transition metal dichalcogenides(TMDs)based antibacterial agents has significantly increased in recent *** research interest is driven by their interesting properties such as metallic and semiconducting nature of different phases,electronic confinement,large surface to volume ratio,the possibility of surface functionalization,and their potential application as a material in biomedical *** synthetic strategies have been developed to synthesize monolayered TMDs and their functionalization with different bioactive *** have given a lot of effort to establish the structure-activity correlation between different TMDs and their antibacterial ***,we have reviewed various exfoliation strategies for TMDs,different methods for their functionalization,and the antibacterial activity of different TMDs.

关键词： Transition metal dichalcogenides(TMD) Functionalization Antibacterial activity Antibacterial mechanism

Suppressing the lattice oxygen diffusion via high-entropy oxide construction towards stabilized acidic water oxidation

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Nano Research 2024年第3期17卷 1107-1113页

作者： Jing Ni Zhaoping Shi Yibo Wang Jiahao Yang Hongxiang Wu Pengbo Wang Kai Li Meiling Xiao Changpeng Liu Wei Xing State Key Laboratory of Electroanalytic chemistry Jilin Province Key Laboratory of Low Carbon Chemistry PowerChangchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China School of Applied chemistry and Engineering University of Science and Technology of ChinaHefei 230026China State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China

The scale-up deployment of ruthenium(Ru)-based oxygen evolution reaction(OER)electrocatalysts in proton exchange membrane water electrolysis(PEMWE)is greatly restricted by the poor *** the lattice-oxygen-mediated mechanism(LOM)has been identified as the major contributor to the fast performance degradation,impeding lattice oxygen diffusion to inhibit lattice oxygen participation is imperative,yet remains challenging due to the lack of efficient ***,we strategically regulate the bonding nature of Ru–O towards suppressed LOM via Ru-based high-entropy oxide(HEO)*** lattice disorder in HEOs is believed to increase migration energy barrier of lattice *** a result,the screened Ti_(23)Nb_(9)Hf_(13)W_(12)Ru_(43)O_(x) exhibits 11.7 times slower lattice oxygen diffusion rate,84%reduction in LOM ratio,and 29 times lifespan extension compared with the state-of-the-art RuO_(2) *** work opens up a feasible avenue to constructing stabilized Ru-based OER catalysts towards scalable application.

关键词： ruthenium-based high-entropy oxide suppressing the lattice oxygen diffusion acidic oxygen evolution reaction

A highly reduced Mo_(74) polyoxometalate featuring high proton conductivity accessed by building block strategy

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Science China chemistry 2024年第3期67卷 862-868页

作者： Shi-Yi Liu Xue-Xin Li Wei-Chao Chen Kui-Zhan Shao Xin-Long Wang Chao Qin Zhong-Min Su Key Laboratory of Polyoxometalate and Reticular Material chemistry of Ministry of Education Department of ChemistryNortheast Normal UniversityChangchun 130024China State Key Laboratory of Supramolecular Structure and Materials Institute of Theoretical ChemistryCollege of ChemistryJilin UniversityChangchun 130021China

Highly reduced polyoxometalates(POMs) are predicted to be used as rather high energy density materials;however,it still suffers from the limited cluster species and reduction *** we demonstrate that it is possible to employ the building block strategy to generate a highly reduced polyoxomolybdate(C_(2)H_(8)N)_(14)(NH_(4))_(4)H_(14)[Mo_(48)-ⅤMo_(26)ⅥO_(202)(OH)_(12)(SO_(4))_(6)]·46H_(2)O(Mo_(74)).The fundamental Mo-based{Mo_x}(x=4,5,and 6) building blocks,which are templated by tetra-coordinated anions{MoO_(4)}or{SO_(4)},not only lay foundation for the formation of Mo_(74) featuring an unprecedented reduction ratio of 65%,but also give rise to SBBs-mediated(secondary building blocks) supramolecular dense packing interactions among the isolated Mo_(74) clusters that are favorable for proton ***,high proton conductivity(2.04×10^(-2)S cm^(-1)) had been realized at 50℃ and 90% relative humidity,revealing one of the well-known POMs-based crystalline proton conducting *** result highlights that this building block approach possesses great potential in producing highly reduced POM systems that can achieve controllable reduced ratio and desirable properties.

关键词： polyoxometalate building block molybdenum highly reduced state proton conduction