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De novo synthesis of atropisomeric benzofurans via Cu/SPDO complex catalyzed asymmetric formal [3 + 2] annulation

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Science China Chemistry 2025年第1期 174-180页

作者： Fan-xiao Meng xing-yu wang Ka Lu Ju-Song Yang Fu-Min Zhang Ai-Jun Ma Bao Du Yong-qiang Tu State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical Engineering Lanzhou University School of Chemistry and Chemical Engineering Shanghai Jiao Tong University School of Biotechnology and Health Sciences Wuyi University

Herein, the de novo synthesis of atropisomeric benzofurans through the Cu/spirocyclic-pyrrolidine-oxazoline(SPDO) complex catalyze asymmetric formal [3 + 2] cycloaddition between quinones and ynamides is explored, producing a range of structurally diverse axially chiral benzofurans in satisfactory yields with good to excellent enantioselectivities. Furthermore, density functional theory calculations were applied to explain the possible reaction mechanism.

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Dendrimer-based Hydrogels with Controlled Drug Delivery Property for Tissue Adhesion

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Chinese Journal of Polymer Science 2021年第11期39卷 1421-1430页

作者： Ya-qiang wang xue-yu Dou Hu-Fei wang xing wang De-Cheng Wu Beijing National Laboratory for Molecular Sciences State Key Laboratory of Polymer Physics&ChemistryInstitute of ChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China Department of Biomedical Engineering Southern University of Science and TechnologyShenzhen 518055China

In recent years,the hydrogel-based tissue adhesives have been extensively investigated for their excellent biocompatibility and the ability to be administered directly within the adherent *** meet the requirement for more controllable release in various physiological settings,the components of hydrogel adhesive should be more precisely *** this work,the POSS-ace-PEG hydrogel adhesive was fabricated with the polyacetal dendrimer G1’-[NH3 Cl]16 and poly(ethylene glycol)succinimidyl carbonate(PEG-SC)due to the regular peripheral amino structure of G1’-[NH3 Cl]*** and adhesion tests demonstrated that the hydrogel adhesive had good mechanical and adhesive properties,which could effectively adhere to the pigskin and severed ***,the tissue adhesive exhibited good stability under neutral conditions and the rapid degradation under acidic conditions,allowing for the release of doxycycline hydrochloride(DOX)drug in response to ***,these results suggested that the POSS-ace-PEG adhesive had the potential to provide an alternative to tissue adhesives for applications in pathological environments(inflammation,tumors,etc.).

关键词： Hydrogel adhesive Dendrimer pH-Responsive Drug delivery Tissue adhesion

Vacuolar processing enzyme positively modulates plant resistance and cell death in response to Phytophthora parasitica infection

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Journal of Integrative Agriculture 2023年第5期22卷 1424-1433页

作者： GAO Xian-xian TANG Ya-ling SHI Qing-yao WEI yu-shu wang xiao-xue SHAN Wei-xing qiang xiao-yu State Key Laboratory of Crop Stress Biology for Arid Areas/College of Agronomy Northwest A&F UniversityYangling 712100P.R.China

Oomycete, particularly Phytophthora species, causes the most devastating crop diseases, such as potato late blight,and threatens the sustainable crop production worldwide. Our previous studies identified Resistance to Phytophthora parasitica 1(RTP1) as a negative regulator of Arabidopsis resistance to multiple biotrophic pathogens and RTP1 lossof-function plants displayed rapid cell death and reactive oxygen species(ROS) production during early colonization of P. parasitica. In this study, we aim to decipher the mechanism of RTP1-mediated cell death, and identify a member of vaculoar processing enzymes(VPEs), γVPE, playing a role in rtp1-mediated resistance to P. parasitica and cell death occurrence. Our results showed up-regulation of the expression of γVPE as well as increased VPE/caspase 1-like protease activity in P. parasitica-infected rtp1 mutant plants. Besides, we found that the VPE/caspase 1-like protease activity was required for the cell death occurrence in Arabidopsis plants during the infection of P. parasitica as well as rtp1-mediated resistance to P. parasitica. Further pathogenicity assays on either Arabidopsis γvpe mutant plants or leaves of Nicotiana benthamiana with transient overexpression of γVPE demonstrated γVPE could positively affect plant resistance to P. parasitica. Together, our studies suggest that γVPE might function as an important regulator of plant defense and cell death occurrence in response to P. parasitica infection, and VPE/caspase 1-like protease activity is required for rtp1-mediated resistance to P. parasitica.

关键词： cell death caspase 1 plant resistance Phytophthora parasitica RTP1 susceptibility factor vacuolar processingenzyme

Trimer formation of 6-methyl-1,3,5-triazine-2,4-diamine in salt with organic and inorganic acids:analysis of supramolecular architecture

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Science China Chemistry 2014年第12期57卷 1731-1737,1-2页

作者： xiao Zhen yu wang Wen qiang xue Rui yu ZHAO Lei wang Lei ZHANG YiHeng College of Chemistry and Molecular Engineering Qingdao University of Science and Technology

Although the numbers of co-crystals,salts,polymorphs,hydrates,and solvates are growing steadily,trimers that contain both inorganic and organic acids are still very rare in the Cambridge Structural Database(CSD).When 3,5-dihydroxybenzoic acid was crystallized readily with 6-methyl-1,3,5-triazine-2,4-diamine in a 4:3 ratio of ethanol and water by adding a few drops of nitric acid upon slow evaporation in ambient conditions,6-methyl-1,3,5-triazine-2,4-diamine and 3,5-dihydroxybenzoic acid with the nitric acid form of 1:1:1 an inorganic-organic salt formulated as[(C4H8N5+)·(NO3-)·(C7H6O4)].The supramolecular architecture,which is quite elegant and simple,appeared as stacking of a 3D network in *** transfer from the HNO3to 6-methyl-1,3,5-triazine-2,4-diamine N acceptor(triazine N)occurred in the organic salt and led to the ionic heterosynthon in the *** among the–COOH,–OH,NO3–,and–NH–functional groups for the observed hydrogen bond synthon was examined in the *** adduct,recognition among the constituents is established through N–H···O,O–H···N,and O–H···O hydrogen *** agomelatine molecules are linked through the intermolecular hydrogen bonding interactions(O–H···O)to form a 1D *** addition,the nitric acid anions and base cations act as donors and acceptors of hydrogen bonds and interlink,almost to co-planarity,the hydrogen-bonded chains through interchain N–H···O,O–H···N,as well as O–H···O interactions into a 2D sheet *** N–H···O interactions were found to play an important role in the formation of the final 3D *** salt was characterized by elemental analysis,IR,thermogravimetric analysis,and singlecrystal X-ray diffraction,to better understand how intermolecular interactions influence its supramolecular assembly.

关键词： supramolecular hydrogen bonds crystal structure salt

Lighting up nonbenzenoid acepleiadylene with ultra-narrowband emission through aromaticity modulation

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Science China Chemistry 2023年第12期66卷 3506-3510页

作者： Pengcai Liu xiao-yu Tang Cheng-Zhuo Du Rui xue xing-yu Chen Jiawen Cao xiao-Ye wang State Key Laboratory of Elemento-Organic Chemistry Frontiers Science Center for New Organic MatterCollege of ChemistryNankai UniversityTianjin 300071China

Nonbenzenoid polycyclic arenes have attracted great attention because of their unique topological structures and appealing properties;however,they are generally considered as poor luminescent materials due to the ring puckering behavior of the ***(APD),a nonbenzenoid isomer of pyrene,has been demonstrated as an excellent building block for optoelectronic applications,but its poor photoluminescence quantum yield(PLQY)has hampered its application in luminescent *** that the ring puckering character can be suppressed by increasing the rigidity of the nonhexagon rings,herein,we propose a novel strategy for enhancing the aromaticity of the nonhexagons to improve the PLQYs of APD ***-withdrawing cyano groups are introduced on the five-membered ring of APD to enhance the chargeseparated character and thus the aromaticity of the nonhexagons,endowing the cyano-substituted APDs(CNAPD and 2CNAPD)with better ***,the cyano substitution successfully suppresses the nonradiative energy dissipation caused by the ring puckering,improving the PLQY from 2.4%for APD to 14%for CNAPD,and to 63%for *** addition,the enhanced rigidity also suppresses the vibration sideband of the photoluminescence spectra,leading to an ultra-narrowband emission from 2CNAPD with a full-width at half-maximum(FWHM)of 13 nm(47 me V),which is a new record in organic *** results demonstrate that APD derivatives have great potential in highly efficient luminescent materials with high color purity via the aromaticity regulation strategy,which provides a novel concept for designing nonbenzenoid luminescent materials.

关键词： nonbenzenoid arenes luminescence narrowband emission acepleiadylene

FeNiS_(2)/reduced graphene oxide electrocatalysis with reconstruction to generate FeNi oxo/hydroxide as a highly-efficient water oxidation electrocatalyst

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Rare Metals 2022年第12期41卷 4127-4137页

作者： xiao-Zhen Ren xue-Hui Li yu-Jie Peng Guan-Zhi wang Jie Yin xing-Chuan Zhao Wei wang xiao-Bai wang School of Materials Science and Engineering Liaocheng UniversityLiaocheng 252000China School of Metallurgy and Chemistry Engineering Jiangxi University of Science and TechnologyGanzhou 341000China Department of Materials Application Research AVIC Manufacturing Technology InstituteBeijing 100024China

It is critical to developing electrocatalysts with highly active and cost-effective for oxygen evolution to resolve environmental pollution and energy issues,in which FeNi-based nanomaterials hold a great ***,(Fe_(0.33 )Ni_(0.67))S_(2) and(Fe_(0.33 )Ni_(0.67))S_(2)/reduced graphene oxide(rGO)-x%(x=10,20) composites,which exhibited highly efficient oxygen evolution reaction(OER)electrocatalytic activity under alkaline conditions,were synthesized via a hydrothermal approach and following thermal treatment with sulfur *** from the integrated structure of(Fe_(0.33 )Ni_(0.67))S_(2)and support of conductive graphene backbones,(Fe_(0.33 )Ni_(0.67))S_(2)/rGO-20%electrocatalyst showed the best OER activity with an overpotential of 172 mV at 10 mA·cm^(-2)and Tafel slopes of 45 mV·decade^(-1).The composition,phase,and surface structure of the catalyst were characterized before and after OER *** results indicated that crystal phase of the catalyst was reconstructed to the amorphous crystalline features after OER,with oxidation of iron-nickel sulfide and appearance of Ni-Fe oxo/hydroxide species,which may play a crucial role in the high OER performance as the ***,in a two-electrode system towards overall water splitting with(Fe_(0.33 )Ni_(0.67))S_(2)/rGO-20%/NF and Pt/C/NF as the anode and cathode,respectively,the catalysts exhibited excellent catalytic performance with the voltage of only 1.42 V at 10 mA·cm^(-2).

关键词： Ternary nickel-iron sulfide Reduced graphene oxide(rGO) Electrocatalysts Water oxidation Self-reconstruction

Evolution of the platycodonoid group with particular references to biogeography and character evolution

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Journal of Integrative Plant Biology 2014年第10期56卷 995-1008页

作者： qiang wang xiao-Quan wang Hang Sun Yan yu xing-Jin He De-yuan Hong State Key Laboratory of Systematic and Evolutionary Botany Institute of Botany the Chinese Academy of Sciences Key Laboratory of Biodiversity and Biogeography Kunming Institute of Botany the Chinese Academy of Sciences College of Life Sciences Sichuan University

The Qinghai‐Tibet Plateau（QTP）is an important center of origin and diversification for many northern temperate *** hypothesis＂out‐of‐QTP＂suggests that the majority of northern temperate plants have originated and dispersed from the QTP and adjacent *** interesting question is whether the biogeographic history of the platycodonoids（Campanulaceae）,a group mainly distributed in the QTP and adjacent regions,coincides with the hypothesis＂out‐of‐QTP＂？Furthermore,how have the diagnostic characters of the platycodonoids evolved？In the present study,all 10genera of the platycodonoids were sampled for molecular phylogeny and dating analyses,and ancestral states of distribution and characters were *** results do not support the platycodonoids as an＂out‐of‐QTP＂group,but instead they might have descended from Tethyan *** dispersal and diversification of the platycodonoids in Asia might have been driven by the uplift of the *** present study highlights the importance of the Tethyan Tertiary flora for the origin of the Sino‐Himalayan flora and the influence of the uplift of QTP on diversification of northern temperate *** addition,character state reconstruction reveals that the inferior ovary,capsule,long‐colpate pollen,and chromosome number 2n=14 are probably ancestral states.

关键词： Biogeography Campanulaceae character evolution platycodonoids Qinghai‐Tibet Plateau

Oxidation of Difluorocarbene by Pyridine N-Oxide and Ensuing Access to Carbamoyl Fluorides

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Chinese Journal of Chemistry 2023年第22期41卷 2981-2987页

作者： Hai-Jun Tang xue-Min Shi xiao-yu Zhu Cheng-qiang wang Chao Feng Technical Institute of Fluorochemistry(TiF) Institute of Advanced Synthesis(iAs)State Key Laboratory of Material-Oriented Chemical EngineeringSchool of Chemistry and Moiecular EngineeringNanjing TechUniversity30 South Puzhu RoadNanjingJiangsu211816China

A practical one-pot preparation of carbamoyl fluorides from easily obtained pyridine N-oxide,commercially available secondary amines and synthetically versatile difluorocarbene precursors(Ruppert-Prakash reagent or Chen's reagent)was developed herein,which dexterously resorted to the oxidation of difluorocarbene by external pyridine N-oxide to produce the toxic and gaseous fluorophosgene in *** features of this method include nice functionality tolerance,late-stage modification of drug molecules and the recoveryand recycle of quinoline.

关键词： Difluorocarbene Pyridine N-oxide Fluorophosgene Carbamoyl fluorides Amines Fluorine

Effects of congenital ptosis on the refractive development of eye and vision in children

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International Journal of Ophthalmology(English edition) 2020年第11期13卷 1788-1793页

作者： xiao-yu Zeng Jia-xing wang xiao-Li Qi xue-Han Qian Nan Wei Tianjin Medical University Eye Institute Tianjin Medical University Eye HospitalCollege of Optometry and OphthalmologyTianjin Medical UniversityTianjin 300384China Department of Ophthalmology Emory University School of MedicineAtlantaGeorgia 30322USA

AIM:To investigate the influence of unilateral congenital ptosis on the development of the eye and vision in ***:In this prospective observational study,41 patients with unilateral congenital ptosis were enrolled(age range 3-15y).The blepharoptosis was divided into 3 subgroups according to the margin reflex distance-1(MRD-1),including mild group(MRD-1>2 mm),moderate group(0

关键词： unilateral congenital ptosis axial length AL/CR ratio amblyopia