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A [3+2]–[4+2]–[3+2] Cycloaddition Sequence of Isoquinolinium Ylide

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A [3+2]–[4+2]–[3+2] Cycloaddition Sequence of Isoquinolini...

中国化学会第十四届全国有机合成化学学术研讨会

作者： Ruzhang Liu rong-guo shi Jing Sun Chao-guo Yan College of Chemistry and Chemical Engineering Yangzhou University

As an unique N-ylide, the isoquinolinium ylide, usually generated in situ from the corresponding salt under the base promotion, was also used in the [3+2] cycloadditions. Besides the precursor of the N-ylide, the isoquinolinium salt itself is also a good electron-deficient diene in various inverse electron demand Diels-Alder reactions, and the generated iminium group of the [4+2] cycloadduct induces further nucleophilic attack inter-or intramolecularly. Our group has a long history of interest in heteroaromatic N-ylides, and in the isoquinolinium project we have disclosed that the minor difference of substrates exhibited various reactivities with isoquinolinium ylide, which afforded the [3+2] cycloadducts, 4-substituted isoquinolinium zwitterionic salts, [4+2] cycloadducts, or recombined pyrrolidines, respectively. We conceived that for carefully selected substrates, the enamine group of the first [3+2] cycloadduct should react with a second molecule of isoquinolinium ylide upon the matched HOMO-LUMO interaction, and the generated iminium methylide of [4+2] cycloadduct would proceed to a second [3+2] cycloaddition. A unique [3+2]–[4+2]–[3+2] cycloaddition sequence of isoquinolinium ylide with aromatic aldehydes and indan-1,3-dione is investigated to afford polycyclic compounds with ten stereogenic centers in moderate to high yields. In this three-component reaction, the isoquinolinium salt has a triple function as 1,3-dipole, the electron-rich dienophile, and the electron-deficient diene. It is surprised that the observance of only one diastereoisomer showed very high regioand diastereo-selectivity, and the mechanistic rationale for the stereoselectivity is also discussed.

关键词： Isoquinolinium salt indan-1,3-dione [3+2] cycloaddition [4+2] cycloaddition

Two-carbon ring expansion of isatin:a convenient construction of dibenzo[b,d]azepinone scaffold

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Two-carbon ring expansion of isatin:a convenient constructio...

中国化学会第十三届全国有机合成化学学术研讨会

作者： rong-guo shi Xiao-Hua Wang Ruzhang Liu Chao-guo Yan College of Chemistry ＆ Chemical Engineering Yangzhou University

As a privileged scaffold,dibenzoazepine,a special type of heterocycles with two benzene rings fused to different positions of an azepine group,is used to derive pharmaceutical agents with various pharmacological *** synthetic way to build up the dibenzo[b,d]azepine skeleton would be necessary to accelerate or expand its applications in the drug *** we attempted the multicomponent reaction of isatins,indan-1,3-dione and N-phenacylisoquinolinium salts to get the [3+2] cycloaddition product.a novel [4+1] adduct was achieved from double nucleophilic additions of indan-1,3-dione to the condensation product of isatins and N-phenacylisoquinolinium salts due to the strong electrophilic natures of C1 carbon and carbonyl carbon of N-phenacylisoquinolinium ***,a unique two-carbon ring expansion of isatins has been achieved to conveniently construct the functionalized dibenzo[b,d]azepin-6-ones in moderate to high yield while one carbon is from N-substituent of pyridinium bromide and the other is from indene-1,***,pyridinium bromide with less electron-withdrawing p-nitrobenzyl groupin in the reaction only resulted in a series of zwitterionic compounds.

关键词： multicomponent reaction nitrogen ylide ring-expansion dibenzo[b,d]azepinone

Domino reaction of 1,3-indanedione with 3-arylideneindolin-2-ones or 3-phenacylideneoxindoles

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Domino reaction of 1,3-indanedione with 3-arylideneindolin-2...

中国化学会·第十三届全国物理有机化学学术会议

作者： Chao-guo Yan Jun Cao rong-guo shi Dan Liu Ruzhang Liu Jing Sun College of Chemistry and Chemical Engineering Yangzhou University

＜正＞1,3-Indanedione is an versatile substrates because it has three contiguous electrophilic and nucleophilic reactive *** the other hand,the facile base-catalyzed Knoevenagel condensation of 1,3-indanedione with aromatic aldehydes afforded more reactive dipolarophilic 2-arylidene-1,3-indanediones,which were widely employed in many Michael addition,Diels-Alder reaction,cyclization reaction and domino reactions.

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青少年学生的隐性斜视对立体视觉的影响

国际眼科杂志 2009年第10期9卷 2016-2018页

作者：施国荣金汉珣常州卫生高等职业技术学校医药技术管理系中国江苏省常州市213002 中国江苏省常州市疾病预防控制中心 213003

目的:分析研究探讨青少年学生的隐性斜视对立体视觉的关系或影响。方法:对年龄15～21岁893例学生采用隐斜仪(马氏杆旋转三棱镜)测定远、近隐斜视度,采用"立体视觉检查图"测定立体视觉,包括立体视锐度、交叉视差、非交叉视差。分析屈光... 详细信息

目的:分析研究探讨青少年学生的隐性斜视对立体视觉的关系或影响。方法:对年龄15～21岁893例学生采用隐斜仪(马氏杆旋转三棱镜)测定远、近隐斜视度,采用"立体视觉检查图"测定立体视觉,包括立体视锐度、交叉视差、非交叉视差。分析屈光正常学生中,立体视觉正常与异常者的隐斜视度均值有无差异,分别研究看远、看近时呈内隐斜或外隐斜者的隐斜视度与立体视觉的相关关系。结果:屈光正常学生中,立体视锐度、交叉视差、非交叉视差异常的学生,看远、看近时内、外隐斜视度均值均比立体视锐度、交叉视差、非交叉视差正常的学生高,且均有非常显著的差异。不论看远、看近时的隐斜,也不论内隐斜或外隐斜,隐斜视度与立体视锐度均呈现正相关,与交叉视差、非交叉视差均呈现负相关;相关系数绝对值:看近时的隐斜视度与立体视锐度相关系数内隐斜高于外隐斜,其余相关系数均内隐斜低于外隐斜。结论:青少年学生的隐性斜视同立体视觉关系密切,隐斜视度增大时,对立体视觉的影响是:立体视锐度增大,立体视范围缩小。

关键词：隐斜视立体视觉屈光正常青少年学生

Multiple Tin Compounds Modified Carbon Fibers to Construct Heterogeneous Interfaces for Corrosion Prevention and Electromagnetic Wave Absorption

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Nano-Micro Letters 2025年第1期17卷 507-527页

作者： Zhiqiang guo Di Lan Zirui Jia Zhenguo Gao Xuetao shi Mukun He Hua guo Guanglei Wu Pengfei Yin College of Science Sichuan Agricultural UniversityYa’an 625014People’s Republic of China School of Materials Science and Engineering Hubei University of Automotive TechnologyShiyan 442002People’s Republic of China Institute of Materials for Energy and Environment State Key Laboratory of Bio‑Fibers and Eco‑TextilesCollege of Materials Science and EngineeringQingdao UniversityQingdao 266071People’s Republic of China Shaanxi Key Laboratory of Macromolecular Science and Technology School of Chemistry and Chemical EngineeringNorthwestern Polytechnical UniversityXi’anShaanxi 710072People’s Republic of China

Currently,the demand for electromagnetic wave(EMW)absorbing materials with specific functions and capable of withstanding harsh environments is becoming increasingly ***-component interface engineering is considered an effective means to achieve high-efficiency EMW ***,interface modulation engineering has not been fully discussed and has great potential in the field of EMW *** this study,multi-component tin compound fiber composites based on carbon fiber(CF)substrate were prepared by electrospinning,hydrothermal synthesis,and high-temperature thermal *** utilizing the different properties of different substances,rich heterogeneous interfaces are *** effectively promotes charge transfer and enhances interfacial polarization and conduction *** prepared SnS/SnS_(2)/SnO_(2)/CF composites with abundant heterogeneous interfaces have and exhibit excellent EMW absorption properties at a loading of 50 wt%in epoxy *** minimum reflection loss(RL)is−46.74 dB and the maximum effective absorption bandwidth is 5.28 ***,SnS/SnS_(2)/SnO_(2)/CF epoxy composite coatings exhibited long-term corrosion resistance on Q235 steel ***,this study provides an effective strategy for the design of high-efficiency EMW absorbing materials in complex and harsh environments.

关键词： Electrostatic spinning Component regulation Heterogeneous interfaces Electromagnetic wave absorption Corrosion protection

Conductive Polymer Composites with Gas Sensibility

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Conductive Polymer Composites with Gas Sensibility

2006年海峡两岸高分子学术研讨会

作者： Ming Qiu Zhang, Min Zhi rong and shi guo Chen Materials Science Institute, Key Laboratory for Polymeric Composite and Functional Materials of Ministry of Education, Zhongshan University, Guangzhou 510275

＜正＞Recently, gas sensors or chemically sensitive materials made from conductive polymer composites have received significant attention for use in detecting, quantifying and discriminating among various organic vapors. The electrical resistances of these composites exhibit drastic increases or decreases when the materials are exposed to certain solvent vapors. The mechanism has been described on the basis of percolation theory. Upon exposure to an odorant, the composites will swell to some degrees depending on the polymer-odorant

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三棱镜正位视训练器矫治青少年学生斜视95例

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国际眼科杂志 2007年第6期7卷 1649-1651页

作者：金汉珣施国荣中国江苏省常州市疾病预防控制中心眼视光门诊部 213003 中国江苏省常州市卫生学校视光学部 213002

目的：观察和研究应用三棱镜正位视训练器矫治青少年学生斜视的效果。方法：采用创新设计的由“双片异向旋转三棱镜组”所构成的正位视训练器对双眼有融合能力的内、外斜视学生共95例进行正位视训练3-6mo，对训练前后的斜视度、斜视性... 详细信息

目的：观察和研究应用三棱镜正位视训练器矫治青少年学生斜视的效果。方法：采用创新设计的由“双片异向旋转三棱镜组”所构成的正位视训练器对双眼有融合能力的内、外斜视学生共95例进行正位视训练3-6mo，对训练前后的斜视度、斜视性质、视觉不适症状进行对比观察和研究。结果：训练后，71例外斜视学生的斜视度下降均值为（6．82±2．55）。（P〈0．01），外斜矫治有效率为82％，显效率为15％；24例内斜视学生的斜视度下降均值为（5．71±2．20）。（P〈0．01），内斜矫治的有效率为67％，显效率为17％。显性外斜转为隐性者占21％，间歇性外斜转为隐性者占79％；显性内斜转为隐性者占35％。视觉不适症状有改善者占74％，明显改善者占48％。结论：应用三棱镜正位视训练器对双眼有融合功能的内、外斜视学生进行正位视训练，矫治斜视的效果显著，值得应用。

关键词：斜视正位视训练青少年学生

Low‑Temperature Oxidation Induced Phase Evolution with Gradient Magnetic Heterointerfaces for Superior Electromagnetic Wave Absorption

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Nano-Micro Letters 2025年第1期17卷 191-204页

作者： Zizhuang He Lingzi shi Ran Sun Lianfei Ding Mukun He Jiaming Li Hua guo Tiande Gao Panbo Liu School of Chemistry and Chemical Engineering Northwestern Polytechnical UniversityXi’an 710129People’s Republic of China School of Marine Science and Technology Northwestern Polytechnical UniversityXi’an 710072People’s Republic of China

Gradient magnetic heterointerfaces have injected infinite vitality in optimizing impedance matching,adjusting dielectric/magnetic resonance and promoting electromagnetic(EM)wave absorption,but still exist a significant challenging in regulating local phase ***,accordion-shaped Co/Co_(3)O_(4)@N-doped carbon nanosheets(Co/Co_(3)O_(4)@NC)with gradient magnetic heterointerfaces have been fabricated via the cooperative high-temperature carbonization and lowtemperature oxidation *** results indicate that the surface epitaxial growth of crystal Co_(3)O_(4) domains on local Co nanoparticles realizes the adjustment of magnetic-heteroatomic components,which are beneficial for optimizing impedance matching and interfacial ***,gradient magnetic heterointerfaces simultaneously realize magnetic coupling,and long-range magnetic ***,the synthesized Co/Co_(3)O_(4)@NC absorbents display the strong electromagnetic wave attenuation capability of−53.5 dB at a thickness of 3.0 mm with an effective absorption bandwidth of 5.36 GHz,both are superior to those of single magnetic domains embedded in carbon *** design concept provides us an inspiration in optimizing interfacial polarization,regulating magnetic coupling and promoting electromagnetic wave absorption.

关键词： Magnetic heterointerfaces Phase evolution Interfacial polarization Magnetic coupling Electromagnetic wave absorption

Tranylcypromine upregulates Sestrin 2 expression to ameliorate NLRP3-related noise-induced hearing loss

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Neural Regeneration Research 2025年第5期20卷 1483-1494页

作者： Xihang Chen Zhifeng Chen Menghua Li Weiwei guo Shuolong Yuan Liangwei Xu Chang Lin Xi shi Wei Chen shiming Yang Senior Department of Otolaryngology Head and Neck Surgery Chinese PLA General HospitalChinese PLA Medical SchoolBeijingChina State Key Laboratory of Hearing and Balance Science BeijingChina National Clinical Research Center for Otolaryngologic Diseases BeijingChina Key Laboratory of Hearing Science Ministry of EducationBeijingChina Beijing Key Laboratory of Hearing Impairment Prevention and Treatment BeijingChina Department of Otorhinolaryngology Head and Neck Surgery The First Affiliated Hospital of Fujian Medical UniversityFuzhouFujian ProvinceChina Department of Otolaryngology Head and Neck Surgery The 940th Hospital of Joint Logistics Support Force of Chinese PLALanzhouGansu ProvinceChina Key Laboratory of Tropical Biological Resources of Ministry of Education School of Pharmaceutical SciencesHainan UniversityHaikouHainan ProvinceChina Academician Workstation of Hainan University School of Pharmaceutical SciencesYazhou BaySanyaHainan ProvinceChina

Noise-induced hearing loss is the primary non-genetic factor contributing to auditory ***,there are currently no effective pharmacological interventions for patients with noise-induced hearing ***,we present evidence suggesting that the lysine-specific demethylase 1 inhibitor–tranylcypromine is an otoprotective agent that could be used to treat noise-induced hearing loss,and elucidate its underlying regulatory *** established a mouse model of permanent threshold shift hearing loss by exposing the mice to white broadband noise at a sound pressure level of 120 d B for 4 *** found that tranylcypromine treatment led to the upregulation of Sestrin2(SESN2)and activation of the autophagy markers light chain 3B and lysosome-associated membrane glycoprotein 1 in the cochleae of mice treated with *** noise exposure group treated with tranylcypromine showed significantly lower average auditory brainstem response hearing thresholds at click,4,8,and 16 k Hz frequencies compared with the noise exposure group treated with *** findings indicate that tranylcypromine treatment resulted in increased SESN2,light chain 3B,and lysosome-associated membrane glycoprotein 1 expression after noise exposure,leading to a reduction in levels of 4-hydroxynonenal and cleaved caspase-3,thereby reducing noise-induced hair cell ***,immunoblot analysis demonstrated that treatment with tranylcypromine upregulated SESN2 expression via the autophagy *** treatment also reduced the production of NOD-like receptor family pyrin domaincontaining 3(NLRP3)*** conclusion,our results showed that tranylcypromine treatment ameliorated cochlear inflammation by promoting the expression of SESN2,which induced autophagy,thereby restricting NLRP3-related inflammasome signaling,alleviating cochlear hair cell loss,and protecting hearing *** findings suggest that inhibiting lysine-specific demethylase 1 is a

关键词： 4-hydroxynonenal apoptosis autophagy cleaved caspase-3 inflammation NOD-like receptor family pyrin domain-containing 3(NLRP3) noise-induced hearing loss oxidative stress Sestrin2 tranylcypromine