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Emerging structures and dynamic mechanisms ofγ-secretase for Alzheimer’s disease

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Neural Regeneration Research 2025年第1期20卷 174-180页

作者： Yinglong Miao Michael S.Wolfe Computational Medicine program and Department of Pharmacology University of North Carolina–Chapel HillChapel HillNCUSA Department of Medicinal chemistry University of KansasLawrenceKSUSA

γ-Secretase,called“the proteasome of the membrane,”is a membrane-embedded protease complex that cleaves 150+peptide substrates with central roles in biology and medicine,including amyloid precursor protein and the Notch family of cell-surface *** inγ-secretase and amyloid precursor protein lead to early-onset familial Alzheimer’s disease.γ-Secretase has thus served as a critical drug target for treating familial Alzheimer’s disease and the more common late-onset Alzheimer’s disease as ***,critical gaps remain in understanding the mechanisms of processive proteolysis of substrates,the effects of familial Alzheimer’s disease mutations,and allosteric modulation of substrate cleavage byγ-*** this review,we focus on recent studies of structural dynamic mechanisms ofγ-*** mechanisms,including the“Fit-Stay-Trim,”“Sliding-Unwinding,”and“Tilting-Unwinding,”have been proposed for substrate proteolysis of amyloid precursor protein byγ-secretase based on all-atom molecular dynamics *** an incorrect registry of the Notch1 substrate was identified in the cryo-electron microscopy structure of Notch1-boundγ-secretase,molecular dynamics simulations on a resolved model of Notch1-boundγ-secretase that was reconstructed using the amyloid precursor protein-boundγ-secretase as a template successfully capturedγ-secretase activation for proper cleavages of both wildtype and mutant Notch,being consistent with biochemical experimental *** approach could be potentially applied to decipher the processing mechanisms of various substrates byγ-*** addition,controversy over the effects of familial Alzheimer’s disease mutations,particularly the issue of whether they stabilize or destabilizeγ-secretase-substrate complexes,is ***,an outlook is provided for future studies ofγ-secretase,including pathways of substrate binding and product release,effects of modulators on familial Alzheimer’s disease mutations

关键词： Alzheimer’s disease amyloid precursor protein cryo-EM structures drug design intramembrane proteolysis molecular dynamics Notch

Construction of N-doped copper metal-organic frameworks for promoting photocatalytic carbon dioxide reduction to ethylene

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Science China chemistry 2025年第2期68卷 601-609页

作者： Fan Guo Zong-Zheng He Peng Wang Xiao-Yu Zhang Hongjian Yu Qin-Chao Wang Wei-Yin Sun School of chemistry and Chemical Engineering Yangzhou UniversityYangzhou 225002China Coordination chemistry Institute State Key Laboratory of Coordination ChemistrySchool of Chemistry and Chemical EngineeringNanjing National Laboratory of MicrostructuresCollaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing 210023China

Engineering nonmetallic atom-doped metal-organic framework(MOF)catalyst to promote C−C coupling and realize conversion of CO_(2) into C_(2 )multi-carbon hydrocarbon products is still ***,with 2-methylimidazole as a dopant of N element,an N-doped NH_(2)-CuBDC catalyst was obtained via a facile and simple stirring *** illumination,compared with catalytic CO_(2) reduction to C1 product of CO by original MOF,N-doped NH_(2)-CuBDC can motivate generation of C_(2)H_(4),which is difficult to achieve in photocatalytic system by MOF-based *** transfer rates of photo-generated charges have been expedited due to the high electron density around Cu catalytic sites after *** importantly,C–C coupling intermediate CO–CHO*was identified by in situ Fourier transform infrared spectroscopy during the catalytic CO_(2) reduction reaction process,which further indicates the presence of Cu–N sites in the NH_(2)-CuBDC can facilitate the formation of C2H_(4) *** work uncovers a new paradigm to design photocatalysts for enhancing the reduction of CO_(2) to C_(2) products.

关键词： metal-organic frameworks C-C coupling doping photocatalytic CO_(2) reduction Cu-based catalysts

Dual atom-bridge effect promoting interfacial charge transfer in 2D/2D Cs3Bi2Br9/BiOBr epitaxial heterojunction for efficient photocatalysis

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Chinese Chemical Letters 2025年第2期36卷 218-223页

作者： Yuan Teng Zichun Zhou Jinghua Chen Siying Huang Hongyan Chen Daibin Kuang MOE Key Laboratory of Bioinorganic and Synthetic chemistry LIFM GBRCE for Functional Molecular Engineering School of Chemistry IGCME Sun Yat-sen University National Experimental Teaching Demonstration Center for chemistry College of Chemistry and Chemical Engineering Jishou University

Optimizing the interfacial quality of halide perovskites heterojunction to promote the photogenerated charge separation is of great significance in photocatalytic ***,the delicately regulation of interfacial structure and properties of halide perovskites hybrid is still a big challenge owing to the growth uncontrollability and incompatibility between different *** we use Bi OBr nanosheets as the start-template to in situ epitaxially grow Cs3Bi2Br9nanosheets by“cosharing”Bi and Br atoms strategy for designing a 2D/2D Cs3Bi2Br9/BiOBr *** studies show that the epitaxial heterojunction can optimize the synergistic effect of Bi OBr and Cs3Bi2Br9via the formation of tight-contact interfaces,strong interfacial electronic coupling and charge redistribution,which can not only drive the Z-scheme charge transfer mechanism to greatly promote the spatial separation of electronhole pairs,but also modulate the interfacial electronic structure to facilitate the adsorption and activation of toluene *** heterojunction exhibited 62.3 and 2.4-fold photoactivity improvement for toluene oxidation to benzaldehyde than parental Bi OBr and Cs3Bi2Br9,*** study not only proposed a novel dual atom-bridge protocol to engineer high-quality perovskite heterojunctions,but also uncovered the potential of heterojunction in promoting electron-hole separation as well as the application in photocatalytic organic synthesis.

关键词： Bismuth oxyhalide Bismuth-based perovskite Direct Z-scheme heterojunction Dual atom-bridge effect Photocatalytic C(sp3)-H bond activation

Nucleophilic trifluoromethylation with CF_(3)H/LiHMDS: probing the nucleophilic reactivity of LiCF_(3) species

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Science China chemistry 2025年第2期68卷 505-512页

作者： Yangfan Liu Xiu Wang Chuanfa Ni Jinbo Hu College of chemistry Central China Normal UniversityWuhan 430079China Key Laboratory of Fluorine and Nitrogen chemistry and Advanced Materials Shanghai Institute of Organic ChemistryUniversity of Chinese Academy of SciencesChinese Academy of SciencesShanghai 200032China

The nucleophilic trifluoromethylation involving trifluoromethyllithium(LiCF_(3))species has been an open question since Haszeldine attempted to prepare LiCF_(3) in ***,LiCF_(3) has been used for electrophilic difluoromethylene transfer processes(via elimination of fluoride ions)since ***,we demonstrated that by using a polar solvent such as dimethylformamide(DMF)or hexamethylphosphoramide(HMPA)as the lithium chelator,the in situ deprotonation of fluoroform(HCF_(3))with lithium hexamethyldisilazide(LiHMDS)could generate a tamed LiCF_(3) species that is sufficiently persistent to undergo nucleophilic trifluoromethylation *** nucleophilic reactivity of LiCF_(3) species was probed with several electrophiles,including arylsulfonyl fluorides,diaryl ketones,and silyl *** synthetic utility of this method is demonstrated with the efficient synthesis of highly valuable triflones that are otherwise difficult to synthesize from HCF_(3) using potassium or sodium *** work not only showcases a new protocol for the utilization of fluoroform(an industrial waste with high global warming potential)as the trifluoromethylation reagent,but also provides intriguing insights into the harnessing of nucleophilic reactivity of the transient LiCF_(3) species.

关键词： nucleophilic trifluoromethylation trifluoromethy llithium fluorinated carbanion negative fluorine effect fluorinated carbenoid

High-throughput experimentation and machine learning-promoted synthesis of α-phosphoryloxy ketones via Ru-catalyzed P(O)O–H insertion reactions of sulfoxonium ylides

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Science China chemistry 2025年第2期68卷 679-686页

作者： An Lin Jingyuan Liu Yougen Xu Haiting Wu Yating Chen Yan Zhang Lebin Su Xiaodan Zhao Kuangbiao Liao Institute of Organic chemistry&MOE Key Laboratory of Bioinorganic and Synthetic chemistry School of ChemistrySun Yat-sen UniversityGuangzhou 510006China Guangzhou National Laboratory Guangzhou 510005China Bioland Laboratory Guangzhou 510005China

Herein,we report a novel and highly efficient method for the synthesis ofα-phosphoryloxy carbonyl compounds via Rucatalyzed P(O)O–H insertion reactions of sulfoxonium ylides and phosphinic acids,with the assistance of high-throughput experimentation(HTE)and machine learning(ML).A variety of P(O)O−H derivatives,including diarylphosphates,alkyl phosphates,and alkoxyphosphates,are competent candidates to react with sulfoxonium ylides in this transformation,and variousα-phosphoryloxy carbonyls and propylene phosphates are directly *** approach utilizes readily available sulfoxonium ylide as a carbene precursor,and features mild conditions,operational simplicity,and broad functional groups tolerance,and could be used for late-stage functionalization of structurally complex bioactive ***,a conducive exploration of the reaction space is also conducted(756 reactions)and a machine learning model for reaction yield prediction has been developed and applied,showcasing the practical application of this newly workflow(HTE-ML)in the field of synthetic chemistry.

关键词： α-phosphoryloxy ketones high-throughput experimentation machine learning P(O)O-H insertion sulfoxonium ylides

A review on reactive oxygen species-induced mechanism pathways of pharmaceutical waste degradation:Acetaminophen as a drug waste model

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Journal of Environmental Sciences 2025年第1期147卷 688-713页

作者： Saba Humayun Maan Hayyan Yatimah Alias Department of chemistry Faculty of ScienceUniversity of MalayaKuala Lumpur 50603Malaysia University of Malaya Centre for Ionic Liquids University of MalayaKuala Lumpur 50603Malaysia Chemical Engineering program Faculty of Engineering and TechnologyMuscat UniversityMuscat P.C.130Oman

Innately designed to induce physiological changes,pharmaceuticals are foreknowingly hazardous to the *** oxidation processes(AOPs)are recognized as a set of contemporary and highly efficient methods being used as a contrivance for the removal of pharmaceutical *** reactive oxygen species(ROS)are formed in these processes to interact and contribute directly toward the oxidation of target contaminant(s),a profound insight regarding the mechanisms of ROS leading to the degradation of pharmaceuticals is fundamentally *** conceptualization of some specific reaction mechanisms allows the design of an effective and safe degradation process that can empirically reduce the environmental impact of *** review mainly deliberates themechanistic reaction pathways for ROS-mediated degradation of pharmaceuticals often leading to complete mineralization,with a focus on acetaminophen as a drug waste model.

关键词： Wastewater treatment Ionic liquid Hydroxyl radical Superoxide Pharmaceutical contaminant Advanced oxidation process Deep eutectic solvent Hydrogen peroxide

Alumina supported platinum-ceria catalyst for reverse water gas shift reaction

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Journal of Rare Earths 2025年第2期43卷 284-294页

作者： Na Jiang Weiwei Wang Haoxin Liu Meiyao Wu Chunjiang Jia Key Laboratory for Colloid and Interface chemistry Key Laboratory of Special Aggregated MaterialsSchool of Chemistry and Chemical EngineeringShandong University

The activation of CO2molecules is a fundamental step for their effective *** highdensity oxygen vacancies on the surface of reducible oxides is pivotal for the activation of *** this work,we prepared a series of 0.5PtxCe/Al2O3（x=1,5,10,or 20） catalysts with varying Ce loading and 0.5 wt% of Pt for the reverse water gas shift（RWGS） *** size of CeO2particle increases with Ce ***,the 0.5Pt5Ce/Al2O3catalyst with an average CeO2particle size of 5.5 nm exhibits a very high CO2conversion rate(116.4×10-5molCO2/(gcat·s)) and CO selectivity（96.1%） at 600℃.Our experimental findings reveal that the small-size CeO2in 0.5Pt5Ce/Al2O3possesses a greater capacity to generate reactive oxygen vacancies,promoting the adsorption and activation of *** addition,the oxygen vacancies are cyclically generated and consumed during the reaction,which contributes to the elevated catalytic performance of the *** work provides a general strategy to construct rich oxygen vacancies on CeO2for designing high-performance catalysts in C1chemistry.

关键词： CO 2 activation Ceria Oxygen vacancies Size-effect Reverse water gas shift reaction Rare earths

Trinuclear gold-catalyzed site-selective alkylation of peptides

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Science China chemistry 2025年第1期68卷 249-256页

作者： Qing-Yun Fang Chengyihan Gu Yinghan Chen Wencheng Yan Yong Liang Weipeng Li Chengjian Zhu Jie Han Jin Xie State Key Laboratory of Coordination chemistry Jiangsu Key Laboratory of Advanced Organic MaterialsChemistry and Biomedicine Innovation Center(ChemBIC)School of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023China Green Catalysis Center College of ChemistryZhengzhou UniversityZhengzhou 450001China State Key Laboratory of Natural Medicines China Pharmaceutical UniversityNanjing 211198China

Selective modification of peptides has always been a challenging *** selective alkylation of peptides can alter the biological activity and physical properties of molecules,and it has gained significant research *** herein disclose an intriguing gold-catalyzed alkylation of peptides using bench-stable unactivated alkyl bromides under photoredox catalysis.A wide range of structurally diverse primary,secondary and tertiary alkyl bromides serve as effective coupling partners to precisely connect with theα-C(sp^(3))–H in glycine residue of *** protocol demonstrates an exceptionally broad scope for alkyl halides and excellent tolerance for a wide range of useful functional groups.A series of relay transformations to construct cyclic peptides,to proceed click reaction and to realize peptide fluorescence labeling further enhance its synthetic *** addition,mechanistic studies and density functional theory(DFT)calculations reveal an inner-sphere and subsequent outersphere single electron transfer(SET)mechanism.

关键词： gold catalysis peptide alkylation C-C coupling radical

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Research progress of catalysts for direct coal liquefaction

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Journal of Energy chemistry 2025年第1期100卷 481-497页

作者： Wei Song Penggao Liu Xinyue Chen Ting Wang Chunrong He Rui Hao Kaiyu Liu State Key Laboratory of chemistry and Utilization of Carbon Based Energy Resources College of ChemistryXinjiang UniversityUrumqi 830017XinjiangChina College of chemistry and Chemical Engineering Henan Polytechnic UniversityJiaozuo 454003HenanChina Hunan Provincial Key Laboratory of Chemical Power Sources College of Chemistry and Chemical EngineeringCentral South UniversityChangsha 410083HunanChina

Coal direct liquefaction technology is a crucial contemporary coal chemical technology for efficient and clean use of coal resources. The development of direct coal liquefaction technology and the promotion of alternative energy sources are important measures to guarantee energy security and economic security. However, several challenges need to be addressed, including low conversion rate, inadequate oil yield, significant coking, demanding reaction conditions, and high energy consumption. Extensive research has been conducted on these issues, but further exploration is required in certain aspects such as pyrolysis of macromolecules during the liquefaction process, hydrogen activation, catalysts' performance and stability, solvent hydrogenation, as well as interactions between free radicals to understand their mechanisms better. This paper presents a comprehensive analysis of the design strategy for efficient catalysts in coal liquefaction, encompassing the mechanism of coal liquefaction, catalyst construction,and enhancement of catalytic conversion efficiency. It serves as a comprehensive guide for further research endeavors. Firstly, it systematically summarizes the conversion mechanism of direct coal liquefaction, provides detailed descriptions of various catalyst design strategies, and especially outlines the catalytic mechanism. Furthermore, it addresses the challenges and prospects associated with constructing efficient catalysts for direct coal liquefaction based on an understanding of their action mechanisms.

关键词： Direct coal liquefaction Catalysts Mechanismof action Solvent hydrogenation