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Highly Stereoselective Synthesis of 2,2-Disubstituted Vinylphosphonates via Aryl to Vinyl 1,4-Palladium Migration

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Chinese Journal of Chemistry 2022年第18期40卷 2188-2192页

作者： Yan-zhen Chen Geng-Yu Bao Xin-Chen Zhan Jian-Guo fu xiao-Ming Ji Shu-Sheng Zhang Chen-Guo Feng The Research Center of Chiral Drugs Innovation Research Institute of Traditional Chinese MedicineShanghai University of Traditional Chinese MedicineShanghai201203 China

Vinylphosphates play an important role in the fields of synthetic chemistry,pharmaceuticals and material *** is a long-standing challenge to control the geometry of multi-substituted ***,an efficient method for the synthesis of 2,2-disubstituted vinylphosphonates has been *** reaction proceeded via aryl to vinyl 1,4-palladium migration progress,in which two difficulties that the deactivation of palladium catalyst by the coordination of excess secondary phosphine oxide and the competitive cross-coupling to form arylphosphonates are successfully *** judicious selection of phosphine ligand is the key to *** protocol features excellent regio-and stereoselectivitiy,generally excellent reaction yields and broad substrate socpe.

关键词： 1,4-Palladium migration Phosphorylation C-H activation Stereoselectivity Cross-coupling

Monoclonal Antibody-Based Treatments for Neuromyelitis Optica Spectrum Disorders:From Bench to Bedside

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Neuroscience Bulletin 2020年第10期36卷 1213-1224页

作者： Wenli Zhu Yaling Zhang zhen Wang Ying fu Yaping Yan Key Laboratory of the Ministry of Education for Medicinal Resources and Natural Pharmaceutical Chemistry National Engineering Laboratory for Resource Development of Endangered Crude Drugs in Northwest ChinaCollege of Life SciencesShaanxi Normal UniversityXi'an 710119China Department of Neurology Tianjin Neurological InstituteTianjin Medical University General HospitalTianjin 300052China

Neuromyelitis optica(NMO)/NMO spectrum disorder(NMOSD)is a chronic,recurrent,antibodymediated,inflammatory demyelinating disease of the central nervous system,characterized by optic neuritis and transverse *** binding of NMO-IgG with astrocytic aquaporin-4(AQP4)functions directly in the pathogenesis of>60%of NMOSD patients,and causes astrocyte loss,secondary inflammatory infiltration,demyelination,and neuron death,potentially leading to paralysis and *** treatment options,including immunosuppressive agents,plasma exchange,and B-cell depletion,are based on small retrospective case series and open-label *** is noteworthy that monoclonal antibody(mAb)therapy is a better option for autoimmune diseases due to its high efficacy and *** the pathophysiological mechanisms of NMOSD remain unknown,increasingly,therapeutic studies have focused on mAbs,which target B cell depletion,complement and inflammation cascade inactivation,bloodbrain-barrier protection,and blockade of NMO-IgG-AQP4 ***,we review the targets,characteristics,mechanisms of action,development,and potential efficacy of mAb trials in NMOSD,including preclinical and experimental investigations.

关键词： Neuromyelitis optica spectrum disorders Monoclonal antibody AQP4-IgG Astrocyte Central nervous system

Microstructure and Mechanical Behavior of FeNiCoCr and FeNiCoCrMn High-Entropy Alloys Fabricated by Powder Metallurgy

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Acta Metallurgica Sinica(English Letters) 2021年第4期34卷 445-454页

作者： Chenliang Chu Weiping Chen zhen Chen zhenfei Jiang Hao Wang Zhiqiang fu Guangdong Key Laboratory for Advanced Metallic Materials Processing South China University of TechnologyGuangzhou 510640China Shantou Technician College Shantou 515041China

The present work reports a systematic investigation on phase evolution,microstructure and microstructure-property relationship of two typical face-centered cubic(FCC)structured high-entropy alloys(HEAs),FeNiCoCr and FeNiCoCrMn,prepared via mechanical alloying(MA)followed by spark plasma sintering(SPS).Following 50 h of MA,the two HEAs consisted of a mixture of FCC and body-centered cubic *** SPS,the bulk FeNiCoCr alloy showed a primary FCC phase with a small amount of Cr_(23)C_(6) and Cr_(2)O_(3) contaminants,while the bulk FeNiCoCrMn alloy was composed of a primary FCC phase with some(Cr,Mn)23C6 and MnCr_(2)O_(4) *** average grain size of the primary FCC phase in the bulk FeNiCoCr alloy was~416 nm,while that of the primary FCC phase in the bulk FeNiCoCrMn alloy was~547 *** yield strength,compressive strength and strain-to-failure of the bulk FeNiCoCr alloy are 1525 MPa,1987 MPa and 24.4%,respectively,whereas those of the bulk FeNiCoCrMn alloy are 1329 MPa,1761 MPa and 21.9%,*** suggests that the bulk FeNiCoCrMn exhibited lower strength and plasticity in comparison with the bulk FeNiCoCr ***,the smaller grain size of the primary FCC phase in the FeNiCoCr alloy is mainly responsible for the better mechanical performance.

关键词： High-entropy alloy Mechanical alloying Microstructure Strengthening Contaminants

SECOND-ORDER NONLINEAR OPTICAL HYPERBRANCHED POLYMER CONTAINING ISOLATION CHROMOPHORE MOIETIES DERIVED FROM BOTH “H”-TYPE AND STAR-TYPE CHROMOPHORES

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Chinese Journal of Polymer Science 2013年第10期31卷 1415-1423页

作者： Wen-bo Wu Ying-jie fu Can Wang zhen Xu Cheng Ye Jin-gui Qin zhen Li Department of Chemistry Hubei Key Lab on Organic and Polymeric Opto-Electronic MaterialsWuhan University Key Laboratory of Organic Solids Institute of Chemistry Chinese Academy of Sciences

An NLO hyperbranched polymer （HP1） derived from both ＂H＂-type and star-type chromophores was synthesized successfully for the first time with high yield via one-pot ＂A2 ＋ B3＂ Suzuki polymerization reaction. Isolation chromophore was also introduced to further improve its performance. Although under the test conditions, the films of HP1 could not be poled completely, it still demonstrated satisfactory macroscopic NLO effect with the second harmonic generation （SHG） coefficient d33 value of 36 pm/V.

关键词： Hyperbranched polymer NLO Isolation chromophore "H"-type chromophore Star-type chromophore.

Antibonding orbital tailor and stress relief engineering for FeS_(2)complex toward superior sodium storage

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Rare Metals 2024年第10期43卷 5048-5059页

作者： You-Bin Zhang zhen-Guo Qi fu-Sheng Liu Guo-Hui Qin State Key Laboratory Base for Eco-Chemical Engineering College of Chemical EngineeringQingdao University of Science and TechnologyQingdao 266042China Shandong Synergetic Innovation Center of Ecological and Chemical Engineering Qingdao 266042China

The sluggish kinetics behaviors and vast volume variations of Na^(+)hosts to FeS_(2)anode involved intercalation,and conversion reactions plague its applicability of sodium-ion batteries(SIBs).Here,a significantly expedited kinetics via cation intercalation and considerably relieved stress accumulation by constructing the concave scaffold protector are approached for FeS_(2)*** Mn^(2+)intercalation into FeS_(2),a new stable Mn-FeS_(2)was generated with distorted coordination;elevated antibonding orbital occupancy and lowed d band center to the release of more free Na^(+)were achieved,which was further encapsulated by hollow bowl-like carbon spheres(BC)This cation intercalation and concave morphology strategies confer Mn-FeS_(2)@BC significantly enhanced electron ion transport kinetics via reversed electron transfer to FeS_(2)fast desolvation kinetics,and evidently depressed structural deformation during Na^(+)insertion and ***,Mn-FeS_(2)@BC delivers the longevity and stable Na^(+)storage capacity in both half and full cell ***,Mn-FeS_(2)@BC also displays excellen adaptability in a wider temperature *** work proposes new views into the deep regulation of electrochemical performance of transition metal anodes via intercalation chemistry and concave engineering.

关键词： FeS_(2) Intercalation chemistry Concave engineering Sodium capture

Modern tectonic stress field deeply in Xuzhou Coal Mine

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Journal of Coal Science & Engineering(China) 2013年第1期19卷 14-18页

作者： zhen-jie JING fu-ren XIE xiao-feng CUl Jing-fei ZHANG Institute of Crust Dynamics China Seismological Bureau Beijing 100085 China

By inverting fault slip data, the parameters of 12 tectonic stress tensors in the mine region can be determined. The following characteristics can be obtained for recent tectonic stress fields, which are found deep in the study region. The results show that the recent tectonic stress field mainly presents the characteristics of near NWW-SSE maximum compressional stress and near NE-SW minimum extensional stress, while the stress regimes are mainly of strike slip, part of the reverse-fault type. Recent tectonic stress field in the region is characterized by horizontal components. The maximum principal compression stress direction was from NEE to SEE, the average principal compression stress direction was near NWW-SSE maximum compres- sional stress and near NE-SW minimum extensional. The recent tectonic stress field of the studied area can be controlled by a large tectonic stress area.

关键词： Xuzhou region fault slip data tectonic stress field inversion

Reflected Beam Displacements of a Slightly Divergent Ultrasonic Gaussian Beam on a Water-Glass Interface Near Rayleigh Angle Incidence

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Chinese Physics Letters 1999年第11期16卷 819-821页

作者： ZHU Guo-zhen LIU Liang fu De-yong Department of Physics Tsinghua UniversityBeijing 100084

Two reflected beams of a slightly divergent ultrasonic Gaussian beam on a water-glass interface are observed and recorded by a Schlieren system. The lateral displacements of the two reflected beams are measured for incident angle θi in a wide range of 10° around the Rayleigh angle θc. The displacements decrease as the incident angle increases, which is different from the previous predictions for bounded plane-wave beams, where the displacements have extremum at the Rayleigh angle θ*** explanation is based on the fact that the Gaussian beam generated by an ultrasonic transducer with a button (or strip) back electrode is actually slightly divergent. We extend Bertoni and Tamir's theory (Appl. Phys. 2 (1973) 157) to this case, and our calculated curves of the displacements against the incident angle are in agreement with the experimental results for |θi - θc| < 2°.

关键词： slightly incident Gaussian

Development of SRAP Markers Linked to a Gene for Stem Nematode Resistance in Sweetpotato, Ipomoea batatas (L.) Lam.

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Journal of Integrative Agriculture 2013年第3期12卷 414-419页

作者： ZHAO Ning ZHAI Hong YU xiao-xia LIU Zhe-sheng HE Shao-zhen LI Qiang MA Dai-fu LIU Qing-chang Beijing Key Laboratory of Crop Genetic Improvement/Laboratory of Crop Heterosis and Utilization Ministry of Education/China Agricultural University Xuzhou Sweetpotato Research Center

Sequence-related amplification polymorphism （SRAP） markers closely linked to stem nematode resistance gene were developed in sweetpotato, lpomoea batatas （L.） Lam. Using bulked segregant analysis （BSA）, 200 SRAP primer combinations were screened with the resistant and susceptible bulked DNA from the 196 progenies of an F1 single-cross population of resistant parent Xu 781xsusceptible parent Xushu 18, 77 of them showed polymorphic bands between resistant and susceptible DNA. Primer combinations detecting polymorphism between the two bulks were used to screen both parents and 10 individuals from each of the bulks. The results showed that primer combination A9B4 produced 3 specific bands in the resistant plants but not in the susceptible plants, suggesting that the markers, named Nspl, Nsp2 and Nsp3, respectively, linked to a gene for stem nematode resistance. Primer combination A3B6 also produced a SRAP marker named Nsp4 linking to the resistance gene. Amplified analysis of the 196 F1 individuals indicated that the genetic distance between these markers and the resistance gene was 4.7, 4.7, 6.3, and 9.6 cM, respectively.

关键词： Ipomoea batatas (L.) Lam. SRAP marker stem nematode

Modified insulin-like growth factor 1 containing collagen-binding domain for nerve regeneration

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Neural Regeneration Research 2018年第2期13卷 298-303页

作者： Jian-an Li Chang-fu Zhao Shao-jun Li Jun Zhang zhen-hua Li Qiao Zhang xiao-yu Yang Chun-fang Zan Department of Orthopedics Second Hospital of Jilin UniversityChangchunJilin ProvinceChina Department of Orthopedics China-lapan Union Hospitallilin UniversityChangchunlilin ProvinceChina Department of Orthopedics Affiliated Hospital of Changchun University of Traditional Chinese MedicineChangchunlilin ProvinceChina

Insulin-like growth factor 1 （IGF-I） is a potential nutrient for nerve repair. However, it is impractical as a therapy because of its limited half- life, rapid clearance, and limited target specificity. To achieve targeted and long-lasting treatment, we investigated the addition of a binding structure by fusing a collagen-binding domain to IGF- 1. After confirming its affinity for collagen, the biological activity of this construct was examined by measuring cell proliferation after transfection into PC12 and Schwann cells using a 3-（4,5-dimethyl-2-thiazolyl）-2,5-di- phenyl-2-H-tetrazolium bromide assay. Immunofluorescence staining was conducted to detect neurofilament and microtubule-associated protein 2 expression, while real time-polymerase chain reaction was utilized to determine IGF-1 receptor and nerve growth/actor mRNA expression. Our results demonstrate a significant increase in collagen-binding activity of the recombinant protein compared with IGF-1. Moreover, the recombinant protein promoted proliferation of PC12 and Schwann cells, and increased the expression of neurofilament and microtubule-associated protein 2. Importantly, the recombinant protein also stimulated sustained expression of IGF-1 receptor and nerve growth factor mRNA for days. These results show that the recombinant protein achieved the goal of targeting and long-lasting treatment, and thus could become a clinically used factor for promoting nerve regeneration with a prolonged therapeutic effect.

关键词： nerve regeneration insulin-like growth factor I collagen-binding domain fusion protein collagenase targeted therapy neural regeneration