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Trinuclear gold-catalyzed site-selective alkylation of peptides

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Science China Chemistry 2025年第1期 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 Materials Chemistry and Biomedicine Innovation Center (Chem BIC) School of Chemistry and Chemical Engineering Nanjing University Green Catalysis Center College of Chemistry Zhengzhou University State Key Laboratory of Natural Medicines China Pharmaceutical University

Selective modification of peptides has always been a challenging issue. The selective alkylation of peptides can alter the biological activity and physical properties of molecules, and it has gained significant research interest. We 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 the α-C(sp3)–H in glycine residue of peptides. This 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 practicality. In addition, mechanistic studies and density functional theory(DFT) calculations reveal an inner-sphere and subsequent outersphere single electron transfer(SET) mechanism.

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Hyper-crosslinked Conjugated Microporous Polymers with Increased Micropores Promotes Confining Polymerization for Electromagnetic Absorption Application

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Chinese Journal of Polymer Science 2023年第8期41卷 1305-1316,I0011页

作者： Hao Chen fang-Yuan Chu hai-yan Zhuang lu Wang Zhi-Min Ye Wei Dong Zhi-Peng xie A-Ming xie School of Mechanical Engineering Nanjing University of Science&TechnologyNanjing 210094China State Key Laboratory for Marine Corrosion and Protection Luoyang Ship Material Research Institute(LSMRI)Xiamen 361100China School of Chemistry and Chemical Engineering Nanjing University of Science&TechnologyNanjing 210094China

Conjugated microporous polymers have excellent skeleton structures but poor electrical conductivity limits their applications in microwave *** solve this problem,a strategy of molecular expansion and confining polymerization is proposed in this work to synthesize conductive hyper-crosslinked conjugated microporous *** topology of the conjugated microporous polymer is changed into a three-dimensional skeleton structure with high specific surface area by using molecular expansion technique,and the controlled growth of polypyrrole in the channel constructs a unique network *** balance of excellent composite backbone structure,proper conductivity,attenuation capability and impedance matching enable the material to exhibit electromagnetic wave absorption *** a result,with low filler loading of 10 wt%,a strongest reflection loss of-52.68 d B and a maximum effective bandwidth of 5.76 ***,CST simulations of the radar scattering cross section have been carried out to verify the excellent material *** study provides new concepts for new conductive polymers and broadens the application of hyper-crosslinked conjugated microporous polymer in the field of electromagnetic wave absorption.

关键词： Hyper-crosslinked conjugated microporous polymer Electromagnetic wave absorbing Molecular expansion Polypyrrole

An approximate analytical solution for transient gas flows in a vertically fractured well of finite fracture conductivity

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Petroleum Science 2022年第6期19卷 3059-3067页

作者： Yun-Hu lu Kang-Ping Chen yan jin Hong-Da Li Quan xie College of Petroleum Engineering China University of Petroleum(Beijing)Beijing102200China School for Engineering of Matter Transport and EnergyArizona State UniversityTempeAZ85287-6106USA Discipline of Petroleum Engineering WA School of Mines:MineralsEnergy and Chemical EngineeringCurtin University26 Dick Perry Avenue6151KensingtonWestern AustraliaAustralia

An analytical solution in physical variable space is presented for transient gas flows during constant-rate production from a vertically-fractured well in an infinite homogeneous reservoir with finite fracture *** solution is based on the short-time asymptotic solution and a new approximate transient elliptical flow solution,which covers transient flows from the bilinear flow regime to the pseudo-radial flow *** solution covers the well-known asymptotic solutions in both short-and long-time limits of bilinear and pseudo-radial *** analytical model provides a practical and reliable engineering tool to evaluate the fractured reservoir properties,which can be programmed using a spreadsheet.

关键词： Transient gas pressure Fractured well Analytical solution

Perilipin Gene 1237 T>C Polymorphism is not Associated with Obesity Risk in Northern Chinese Han Adults

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Biomedical and Environmental Sciences 2009年第5期22卷 442-447页

作者： DONG-SHENG HU jinG xie DA-hai YU GuO-HENG XU JIE lu jin-XIU yanG CHUN-yanG LI yan-yan LI Department of Epidemiology College of Public Health Zhengzhou University Zhengzhou 450001 Henan China Population Health Unit Centre for Eye Research Australia University of Melbourne Level 132 Gisborne Street East Melbourne VIC 3002 Australia Department of Evidence-Based Medicine and Division of Population Genetics Cardiovascular Institute and Fuwai Hospital Chinese Academy of Medical Sciences and Peking Union Medical College Beijing 100037 China Department of Physiology Beijing University Medical Sciences Center Beijing 100083 China

Objective To identify the association between PLIN 1237 polymorphism and obesity in Chinese Han adults. Methods A total of 994 adults （157 obese subjects, 322 overweight subjects, and 515 normal controls） were recruited from two rural communities. PLIN 1237 polymorphism was genotyped by polymerase chain reaction-restriction-fragment-length-polymorphism （PCR-RFLP）. Association between PLIN polymorphisms and obesity status was estimated by ordinal logistic regression. Results The three genotypes of,PLIN 1237 were detected with a percentage of 54.3%, 37.1%, and 8.6% in TT, TC, and CC genotypes, respectively. For the PLIN 1237 polymorphism locus, the frequency of alleles T and C was 0.73 and 0.27, respectively. The PLIN 1237 polymorphisms were in Hardy-Weinberg equilibrium. PLIN 1237 polymorphism was not associated with obesity. The odds ratio for overweight or obesity for the CC＋TC genotype was 0.8（0.4, 1.4） in women （P=-0.4） and 0.6 （0.3, 1.3） in men （P=-0.2） after adjustment for age, education, household income and alcohol consumption, smoking, and physicalactivity. Conclusion Chinese Han adults have a lower frequency of variant-allele C in PLIN1237. PLIN1237 T〉C polymorphism is not significantly associated with obesity in northern Chinese adults.

关键词： Perilipin Polymorphism Obesity

Catalysts for Hydration of Cyclohexene to Cyclohexanol

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Chemical Research in Chinese Universities 2013年第4期29卷 743-746页

作者： fang De-ren lu jin-yan ZHANG Hui-min LI Jie WANG yan-yan Shandong Provincial Key Lab of Chemical Engineering Institute of Applied Catalysis Yantai University Yantai 264005 P. R. China

The hydration of cyclohexene was determined in a stirred tank of 100 mL in a batch mode in the presence of modified or unmodified resin as catalyst. The ion-exchange sulfonate resin was modified with alkyl secondary amine. At an optimum amination rate of 15%, the conversion of cyclohexene reached to 22% and the selectivity of cyclohexanol was 95.6%. In a temperature range of 90--150℃, the activity and selectivity of the modified resin ca- talyst were much higher than those of the unmodified resin catalyst, which was attributed to the inclusion formed between cyclohexene and alkyl chain and also the quasi-lipophilic phase formed around the outer surface of resin beads. The formed quasi-lipophilic phase formed enhanced the conversion of cyclohexene and depressed the forma- tion of by-products.

关键词： Hydration Cyclohexene Ion-exchange resin Modification Aminate rate

Microstructure evolution and reaction behavior of Cu–Ni alloy and B4C powder system

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Progress in Natural Science:Materials International 2021年第1期31卷 55-62页

作者： Lei Jia Ming-fang yang Zhen-lin lu jin Xu Hui xie Katsuyoshi Kondoh School of Materials Science and Engineering Xi'an University of Technology School of Materials Engineering Xi'an Aeronautical University Joining and Welding Research Institute Osaka University

Microstructure evolution and reaction behavior of Cu–Ni alloy and B4C power system was studied by in-situ and static experimental investigations along with theoretical calculations. The reaction process was as follows. Firstly,B4C decomposed into B and C atoms, and then B atoms diffused into Cu–Ni matrix, leading to the formation of Ni2B particles. Subsequently, Ni atoms diffused into B4C, forming a loose mixture of Ni2B and amorphous C at the initial powder boundary. Finally, with the completion of reaction, Ni2B particles at the powder boundary grew into a monolithic block, and then C substance was excluded out and accumulated at the edge of this monolithic Ni2B block. It is believed that the formation of Ni2B phase is caused by the most negative change of Gibbs free energy among all the potential reactions between Ni–B and Ni–B4C systems.

关键词： Metal-matrix composites Reaction behavior Microstructure evolution Cu–Ni/B4C composite In-situ experiment

A comparison study on single metal atoms(Fe,Co,Ni)within nitrogen-doped graphene for oxygen electrocatalysis and rechargeable Zn-air batteries

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Chinese Chemical Letters 2023年第6期34卷 531-536页

作者： Shuai xie Hongchang jin Chao Wang Huanyu xie Ying-Rui lu Ting-Shan Chan Wensheng yan Song jin Hengxing Ji School of Chemistry and Material Sciences CAS Key Laboratory of Materials for Energy ConversionUniversity of Science and Technology of ChinaHefei 230026China National Synchrotron Radiation Laboratory University of Science and Technology of ChinaHefei 230026China National Synchrotron Radiation Research Center 300 HsinchuTaiwanChina

Single atom catalysts(SACs)with atomically dispersed transition metals on nitrogen-doped carbon supports have recently emerged as highly active non-noble metal electrocatalysts for oxygen reduction reaction(ORR)and oxygen evolution reaction(OER),showing great application potential in Zn-air ***,because of the complex structure-performance relationships of carbon-based SACs in the oxygen electrocatalytic reactions,the contribution of different metal atoms to the catalytic activity of SACs in Zn-air batteries still remains *** this study,SACs with atomically dispersed transition metals on nitrogen-doped graphene sheets(M-N@Gs,M=Co,Fe and Ni),featured with similar physicochemical properties and M-N@C configurations,are *** comparing the on-set potentials and the maximum current,we observed that the ORR activity is in the order of Co-N@G>Fe-N@G>Ni-N@G,while the OER activity is in the order of Co-N@G>Ni-N@G>Fe-N@*** Zn-air batteries with Co-N@G as the air cathode catalysts outperform those with the Fe-N@G and Ni-N@*** is due to the accelerated charge transfer between Co-N@C active sites and the oxygen-containing *** study could improve our understanding of the design of more efficient bifunctional electrocatalysts for Zn-air batteries at the atomic level.

关键词： M-N@C catalysts Oxygen reduction reaction Oxygen evolution reaction Single atom catalysts Zn-air batteries

Genetic Analysis and Molecular Mapping of an All-Stage Stripe Rust Resistance Gene in Triticum aestivum-Haynaldia villosa Translocation Line V3

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Journal of Integrative Agriculture 2013年第12期12卷 2197-2208页

作者： HOU lu MA Dong-fang HU Mao-lin HE Miao-miao lu yan jinG jin-xue State Key Laboratory of Crop Stress Biology for Arid Areas College of Plant ProtectionNorthwest A&F University Qinghai Academy of Agriculture and Forestry Science Department of Plant Pathology China Agricultural University/Key Laboratory of Plant PathologyMinistry of Agriculture

Triticum aestivum-Hayaldia villosa translocation line V3 has shown effective all-stage resistance to the seven dominant pathotypes of Puccinia striiforms *** prevalent in *** elucidate the genetic basis of the resistance,the segregating populations were developed from the cross between V3 and susceptible genotype Mingxian 169,seedlings of the parents and F 2 progeny were tested with six prevalent pathotypes,including CYR29,CYR31,CYR32-6,CYR33,Sun11-4,and Sun11-11,F 1 plants and F 3 lines were also inoculated with Sun11-11 to confirm the result *** genetic studied results showed that the resistance of V3 against CYR29 was conferred by two dominant genes,independently,one dominant gene and one recessive gene conferring independently or a single dominant gene to confer resistance to CYR31,two complementary dominant genes conferring resistance to both CYR32-6 and Sun11-4,two independently dominant genes or three dominant genes（two of the genes show cumulative effect） conferring resistance to CYR33,a single dominant gene for resistance to *** gene analog polymorphism（RGAP） and simple-sequence repeat（SSR） techniques were used to identify molecular markers linked to the single dominant gene（temporarily designated as YrV3） for resistance to Sun11-11.A linkage map of 2 RGAP and 7 SSR markers was constructed for the dominant gene using data from 221 F 2 plants and their derived F 2：3 lines tested with Sun11-11 in the *** of the complete set of nulli-tetrasomic lines of Chinese Spring with a RGAP marker RG1 mapped the gene on the chromosome 1B,and then the linked 7 SSR markers located this gene on the long arm of chromosome *** linkage map spanned a genetic distance of 25.0 cM,the SSR markers Xgwm124 and Xcfa2147 closely linked to YrV3 with genetic distances of 3.0 and 3.8 cM,*** on the linkage map,it concluded that the resistance gene YrV3 was located on chromosome arm *** chromosomal location,

关键词： Haynaldia villosa translocation line stripe rust RGAP-SSR molecular mapping

The potential impact of clinical factors on blood-based biomarkers for Alzheimer’s disease

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Translational Neurodegeneration 2023年第1期12卷 353-356页

作者： Fengfeng Pan yan lu Qi Huang fang xie jingye yang Qihao Guo Department of Gerontology Shanghai Sixth People’s Hospital Affiliated to Shanghai Jiao Tong University School of MedicineShanghai 200233China PET Center Huashan HospitalFudan UniversityShanghai 200233China

With the development of testing technologies,blood-based biomarkers for Alzheimer’s disease(AD)such as amyloid-β(Aβ),phosphorylated tau(P-tau),and neuro-filament light(NfL)have shown potential value in pre-dicting AD pathology and disease progression[1].To better interpret the detection results,it is essential to understand what factors would affect the concentrations of these *** standardized testing meth-ods may reduce the influence of pre-analytical factors,demographic factors and clinical comorbidities may still affect blood biomarker levels[2,3].Previous studies have shown inconsistent results in this *** example,the apolipoprotein E(APOE)ε4 genotype was associated with a lower Aβ42/Aβ40 ratio in a cohort with different cognitive status but not in a population with or without AD[2,4].In a cohort where most participants had no cognitive impairment,males had higher plasma P-tau levels than females,whereas this was not the case in another group composed mostly of cognitively impaired participants[3,5].

关键词： clinical Alzheimer impaired