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Synthesis of O-glycosylα-aryl nitrones 被引量:3
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作者 Ying Fu Huai Yuan Zhang Yan Hua Liu Xue Feng Li Dan Feng Huang Yu Lai Hu 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第9期1075-1078,共4页
α-Aryl nitrone are one of the most useful kinds of nitrones and have been extensively explored in recent years.However,the sugar moieties have not been introduced into these molecules before.We presented here an effi... α-Aryl nitrone are one of the most useful kinds of nitrones and have been extensively explored in recent years.However,the sugar moieties have not been introduced into these molecules before.We presented here an efficient synthesis ofα-aryl nitrone Oglycosides via condensation of N-substituted hydroxylamine and aryl aldehydes glycosides in benzene. 展开更多
关键词 nitrones GLYCOSIDES Aryl aldehyde HYDROXYLAMINE SYNTHESIS
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Stereoselective construction of azepine-containing bridged scaffolds via organocata-lytic bicyclization of yne-allenone esters with nitrones
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作者 Meng-Fan Li Shao-Qing Shi +6 位作者 Ting Xu Qian Zhang Wen-Juan Hao Shu-Liang Wang Jianyi Wang Shu-Jiang Tu Bo Jiang 《Chinese Chemical Letters》 SCIE CAS CSCD 2023年第4期309-312,共4页
A new organocatalytic double annulation cascade involving scission/recombination of N-O bonds of nitrones is reported for the first time, and used to produce a range of hitherto unprecedented tricyclic bridged-fused b... A new organocatalytic double annulation cascade involving scission/recombination of N-O bonds of nitrones is reported for the first time, and used to produce a range of hitherto unprecedented tricyclic bridged-fused benzo[d]azepines bearing three stereogenic centers with moderate to good yields and complete diastereoselectivity. A quinine-catalyzed reaction of yne–allenone esters with nitrones worked well and provided a convergent and regioselective pathway to access these three-dimensional scaffolds from the planar conjugated system. Density functional theory(DFT) calculations have been applied to understand the key process for forming diradical intermediates. 展开更多
关键词 BICYCLIZATION DIASTEREOSELECTIVITY Organocatalysis Bridged heterocycles YNE-allenone esters nitrones
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Solar Thermochemical Reactions IV: Unusual Reaction of Nitrones with Acetonitrile Derivatives Induced by Solar Thermal Energy
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作者 Ramadan Ahmed Mekheimer Khadijah Mohamed Al-Zaydi +1 位作者 Asma Al-Shamary Kamal Usef Sadek 《Green and Sustainable Chemistry》 2011年第4期176-181,共6页
The behaviour of cyanothioacetamide 1 and the acetonitrile derivatives 6 and 10, respectively, towards the nitrones 2a-i induced by free solar thermal energy is reported. Structures and reaction mechanisms are also di... The behaviour of cyanothioacetamide 1 and the acetonitrile derivatives 6 and 10, respectively, towards the nitrones 2a-i induced by free solar thermal energy is reported. Structures and reaction mechanisms are also discussed. 展开更多
关键词 nitrones Cyanothioacetamide 2-(Hetaryl)Acetonitrile DERIVATIVES Synthesis SOLAR Thermal Energy.
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Selective Deoxygenation of Nitrones Mediated by Sm/CoCl_26H_2O Reductive System
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作者 Ji Ming ZHANG Yong Min ZHANG 《Chinese Chemical Letters》 SCIE CAS CSCD 2001年第11期945-946,共2页
In the presence of metallic samariumcobalt (II) chloride hexahydrate, the nitrones can be reduced to the corresponding imines in moderate to high yields under mild and neutral conditions.
关键词 NITRONE SAMARIUM cobalt (II) chloride hexahydrate.
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Selective 6π-Electrocyclization of N-Vinyl-α,β-Unsaturated Nitrones to Prepare Polysubstituted Pyridine Derivatives
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作者 Li-Yao Ding Yan-Jiao Lu +4 位作者 Jin-Hong Pang Hai-Fang Lin Chun-Hua Chen Hong-Yan Bi Dong-Liang Mo 《Chinese Journal of Chemistry》 2025年第11期1287-1292,共6页
Comprehensive Summary.Herein,we have developed a facile method for the synthesis of various polysubstituted pyridine derivatives through selective 6π-electrocyclization of N-vinyl-α,β-unsaturated nitrones.It was fo... Comprehensive Summary.Herein,we have developed a facile method for the synthesis of various polysubstituted pyridine derivatives through selective 6π-electrocyclization of N-vinyl-α,β-unsaturated nitrones.It was found that gold catalysts promoted carbon-6π-electrocyclization of N-vinyl-α,β-unsaturated nitrones to afford 6-alkenyl pyridine N-oxides in 43%—75%yields,whereas copper catalysts facilitated oxygen-6π-electrocyclization to give 6-epoxy pyridines in 41%—83%yields.The present method features broad substrate scope,good functional group tolerance,high cyclization selectivity,and diversity of polysubstituted pyridine scaffolds. 展开更多
关键词 nitrones 6π-Electrocyclization Gold catalysis Copper catalysis PYRIDINE Nitrogen heterocycles EPOXIDATION CYCLIZATION
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A Tandem Route toward Isoxazolidine Fused Phospholene Skeleton Involving Dearomative[3+2]Cycloaddition of P-Heteroarenes and Nitrones
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作者 Chenyong Xu Yingqiang Wang +2 位作者 Meng Xiao Rongqiang Tian Zheng Duan 《Chinese Journal of Chemistry》 2025年第10期1161-1166,共6页
The demands for effective assembly of structurally complex molecular scaffolds from simple starting materials are continuously growing along with the development of organic chemistry.We have developed a tandem approac... The demands for effective assembly of structurally complex molecular scaffolds from simple starting materials are continuously growing along with the development of organic chemistry.We have developed a tandem approach that assembles simple 6-chloroethylphosphane,alkynyl imines(or alkynyl ketones),and nitrones into structurally complex isoxazolidine fused phospholene scaffolds through a sequential process involving phospha-Michael addition,intramolecular cyclization,and dearomatizing[3+2]cycloaddition reactions.The isoxazolidine-fused phospholene has three heteroatoms,including a junction phosphorus atom.After removing the coordinated tungsten group,these compounds can serve as potential P-stereogenic ligands and may have biological activities.Contrary to pyrroles and furans,the aromatic 2-phosphapyrroles and 2-phosphafurans are good 2r-electron candidates in the dearomative[3+2]cycloaddition reactions due to the poor overlap of the 2p-3p orbitals of the C=P moiety. 展开更多
关键词 CYCLOADDITION PHOSPHANE Heterocycles NITRONE Alkynyl imine Dearomatization Phospholene Michael addition
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Yb(OTf)_(3)-Catalyzed Asymmetric[3+3]Cycloaddition of N-Vinyl Nitrones with Activated Cyclopropanes to Prepare 1,2-Oxazines
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作者 Yu-Zheng Wu Yue Leng +4 位作者 Yi-Xin Chen Shi-Qiu Huang Ning Zou Chun-Hua Chen Dong-Liang Mo 《Chinese Journal of Chemistry》 2025年第4期417-422,共6页
We described a Yb(OTf)_(3) combined with Pybox ligand catalyzed asymmetric[3+3]cycloaddition of N-vinyl cinnamaldehyde nitrones with activated cyclopropanes to prepare various functionalized 1,2-oxazines in 24%—95% y... We described a Yb(OTf)_(3) combined with Pybox ligand catalyzed asymmetric[3+3]cycloaddition of N-vinyl cinnamaldehyde nitrones with activated cyclopropanes to prepare various functionalized 1,2-oxazines in 24%—95% yields and 22%—96%ee.Experimental results revealed that the reaction underwent a domino[3+3]cycloaddition,dealkenylation,and aza-1,4-addition in three steps.The chiral 1,2-oxazine could be obtained in gram scales and easily converted into various 1,2-oxazine scaffolds.The present method features broad substrate scope,good functional group compatibility,three-component domino reaction,and asymmetric[3+3]cycloaddition of N-vinyl nitrones with activated cyclopropanes. 展开更多
关键词 CYCLOADDITION Cyclopropane NITRONE 1 2-Oxazine Asymmetric catalysis Domino reactions Michael addition N-Heterocycle
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On Water: Free Catalysis Approach for the Synthesis of Nitrones from Hydroxamic Acids and Dimethy/ Diethyl Acetylenedicarboxylate 被引量:1
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作者 Jian Li Yongqin He +4 位作者 Xiaoyu Ren Xiaokang Shi Sizhuo Yang Xiai Gao Guosheng Huang 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2013年第8期1003-1006,共4页
Benzohydroxamic acid reacts with dimethyl acetylenedicarboxylate in the presence of 10 mol% NaOAc to gen- erate (E)-N-(1,4-dimethoxy-l,4-dioxobutan-2-ylidene)-l-phenylcarboxamide oxide in good-to-excellent yield i... Benzohydroxamic acid reacts with dimethyl acetylenedicarboxylate in the presence of 10 mol% NaOAc to gen- erate (E)-N-(1,4-dimethoxy-l,4-dioxobutan-2-ylidene)-l-phenylcarboxamide oxide in good-to-excellent yield in water at room temperature for 2 h, which supplies a simple, efficient and environmentally friendly method to syn- thesize a wide range of nitrones. The benefits of this strategy not only conform to the requirment of green chemisty, but also possess atom economy. 展开更多
关键词 nitrones benzohydroxamic acid dimethyl acetylenedicarboxylate environmentally friendly greenchemisty
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[3+3] Formal Cycloadditions of Nitrones from Isatins and Azaoxyallyl Cations for Construction of Spirooxindoles 被引量:1
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作者 Weijia Lin Gu Zhan +2 位作者 Minglin Shi Wei Du Yingchun Chen 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2017年第6期857-860,共4页
A [3+3] formal cycloaddition reaction between in situ formed azaoxyallyl cations and nitrones from isatins has been developed, furnishing a spectrum of spiro[1,2,4-oxadiazinan-5-one]oxindoles in good to excellent yie... A [3+3] formal cycloaddition reaction between in situ formed azaoxyallyl cations and nitrones from isatins has been developed, furnishing a spectrum of spiro[1,2,4-oxadiazinan-5-one]oxindoles in good to excellent yields with excellent diastereoselectivity. This method provides direct and efficient access to potentially bioactive spirooxin- doles incorporating a six-membered heterocyclic scaffold. 展开更多
关键词 CYCLOADDITION SPIROOXINDOLES azaoxyallyl cations nitrones 1 3-dipoles
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Unusual Cycloadducts from the Dipolar Cycloaddition of Allenyl Perfluoroalkyl Sulfones to Nitrones
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作者 王小进 刘金涛 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2007年第5期649-652,共4页
The dipolar cycloaddition reaction of allenyl perfluoroalkyl sulfones (1) to nitrones (2) was described. Unlike nonfluorine-containing allenyl sulfones, 1 reacted readily with 2 in ether at room temperatttre and u... The dipolar cycloaddition reaction of allenyl perfluoroalkyl sulfones (1) to nitrones (2) was described. Unlike nonfluorine-containing allenyl sulfones, 1 reacted readily with 2 in ether at room temperatttre and unusual zwitterionic cycloadducts (3) were obtained in good yields due to the strong electron-withdrawing effect of perfluoroalkyl groups. The structure of 3 was characterized by spectral analyses and X-ray crystallography. 展开更多
关键词 allenyl perfluoroalkyl sulfone NITRONE dipolar cycloaddition ZWITTERION
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Synthesis of 5-Fluoroalkyl Isoxazolidines via 1,3-Dipolar Cycloaddition of Ethyl 2-Hydropolyfluoroalk-2- enoates with Nitrones
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作者 刘金涛 金其辉 +1 位作者 吕贺军 黄维垣 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2004年第9期945-949,共5页
Dipolar cycloaddition reactions of ethyl 2-hydropolyfluoroalk-2-enoates (1) with some nitrones were de-scribed. The reaction of 3,4-dihydroisoquinoline N-oxide (2) with 1 took place readily in methylene chloride at ro... Dipolar cycloaddition reactions of ethyl 2-hydropolyfluoroalk-2-enoates (1) with some nitrones were de-scribed. The reaction of 3,4-dihydroisoquinoline N-oxide (2) with 1 took place readily in methylene chloride at room temperature to give the corresponding 5-fluoroalkylisoxazolidines regioselectively as a mixture of two di-astereoisomers (trans and cis) in high yields, while longer reaction time and higher temperature were needed in the case of non-cyclic nitrones. Under similar conditions the reaction of quinoline N-oxide (14) with 1 did not give the expected adducts and a ring-opening product was obtained. 展开更多
关键词 fluoroalkyl isoxazolidine ethyl 2-hydropolyfluoroalk-2-enoate NITRONE cycloaddition synthesis
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Rapidly diastereoselective assembly of ten-membered N-heterocycles between two 1,3-dipoles and their diversity to access fused N-heterocycles
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作者 Yan Luo Yan-Jiao Lu +6 位作者 Mei-Mei Pan Yu-Feng Liang Wei-Min Shi Chun-Hua Chen Cui Liang Gui-Fa Su Dong-Liang Mo 《Chinese Chemical Letters》 2025年第5期211-217,共7页
The development of general and practical strategies toward the construction of medium-sized rings is still challenging in organic synthesis,especially for the multiple stereocenters control of substituted groups on th... The development of general and practical strategies toward the construction of medium-sized rings is still challenging in organic synthesis,especially for the multiple stereocenters control of substituted groups on the ring owing to the long distance between groups.Thus,stereoselective synthesis of multi-substituted ten-membered rings is attractive.Herein,a rapid assembly of various highly substituted ten-membered nitrogen heterocycles between two 1,3-dipoles through a tandem[3+3]cycloaddition/aza-Claisen rearrangement of N-vinyl-α,β-unsaturated nitrones and aza-oxyallyl or oxyallyl cations are disclosed.Products containing two or multiple stereocenters could be obtained in up to 96%yield with high regioselectivity and diastereoselectivity.Selective N-O bond cleavages of ten-membered nitrogen heterocycles lead to various novel 5,6,6-perifused benzofurans,bicyclo[4.4.0]or bicyclo[5.3.0]skeletons containing three or multiple continuous stereocenters in good yields and high diastereoselectivity.Biological tests show that the obtained ten-membered N-heterocycles and bicyclo[4.4.0]skeletons inhibited nitric oxide generation in LPS-stimulated RAW264.7 cells and might serve as good anti-inflammatory agents. 展开更多
关键词 1 3-Dipole Ten-membered N-heterocycles Aza-Claisen rearrangement [3+3]Cycloaddition NITRONE Anti-inflammatory
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Nitronic50奥氏体不锈钢的热变形行为 被引量:1
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作者 梁剑雄 王长军 +3 位作者 胡家齐 刘振宝 孙永庆 杨志勇 《金属热处理》 CAS CSCD 北大核心 2017年第9期6-10,共5页
在变形温度为950~1150℃,应变速率为0.01~10 s^(-1)、工程应变量为0.6的条件下,通过Gleeble-3800热模拟试验机对Nitronic50奥氏体不锈钢进行了单道次热压缩变形试验。通过引用Zener-Hollomon参数,对Nitronic50钢进行了本构方程的构建,... 在变形温度为950~1150℃,应变速率为0.01~10 s^(-1)、工程应变量为0.6的条件下,通过Gleeble-3800热模拟试验机对Nitronic50奥氏体不锈钢进行了单道次热压缩变形试验。通过引用Zener-Hollomon参数,对Nitronic50钢进行了本构方程的构建,不同变形条件下计算得到的峰值应力值与实际峰值应力值吻合程度较高。通过动态材料模型绘制了Nitronic50钢的能量耗散图,并结合变形后的组织发现能量耗散低反而易于得到较好的热变形组织,本试验条件下最佳的热变形工艺为变形温度在1000℃附近,变形速率1~10 s^(-1)。 展开更多
关键词 Nitronic50钢 热变形 本构方程 能量耗散图
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Nitronic 50不锈钢低温冲击韧性大幅降低原因分析 被引量:2
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作者 孙德文 陈万华 +1 位作者 祝长江 牟志超 《理化检验(物理分册)》 CAS 2017年第10期750-753,共4页
针对低温风洞运动机构用Nitronic 50奥氏体不锈钢在复检中出现低温冲击吸收能量显著偏低的现象,对该批次不锈钢和参考样品分别取样,进行了化学成分、金相、扫描电镜以及能谱等分析。结果表明:该批次Nitronic 50不锈钢中存在大量短棒状的... 针对低温风洞运动机构用Nitronic 50奥氏体不锈钢在复检中出现低温冲击吸收能量显著偏低的现象,对该批次不锈钢和参考样品分别取样,进行了化学成分、金相、扫描电镜以及能谱等分析。结果表明:该批次Nitronic 50不锈钢中存在大量短棒状的Al N脆性夹杂物,是导致其低温冲击韧性大幅度降低的主要原因;材料晶粒尺寸偏大且存在混晶现象也降低了其冲击韧性。 展开更多
关键词 低温风洞 Nitronic 50奥氏体不锈钢 低温冲击韧性 AlN夹杂物 晶粒尺寸
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Studies on New Additions to 5-Methoxy-2 (5H)-Furanone: 1, 4-Addition of Grignard Reagents, and 1,3-Dipolar Cycloaddition of Silyl Nitronates 被引量:3
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作者 Zhao Yang WANG Jia Ling CUI +1 位作者 Bao Shan DU Qing Hua CHEN 《Chinese Chemical Letters》 SCIE CAS CSCD 2001年第4期293-296,共4页
1,4-Addition reaction of Grignard's reagent to 5-methoxy-2(5H)-furanone 1 was accomplished. which provided a new possible route for synthesizing beta -alkyl-Y-alkyloxy-Y-butyrolactone. A novel concise method of pr... 1,4-Addition reaction of Grignard's reagent to 5-methoxy-2(5H)-furanone 1 was accomplished. which provided a new possible route for synthesizing beta -alkyl-Y-alkyloxy-Y-butyrolactone. A novel concise method of preparing fused heterocyclic compounds was offered by 1,3-dipolar cycloaddition reaction of silyl nitronates to 1. 展开更多
关键词 Michael addition Grignard reagent 1 3-dipolar cycloaddition silyl nitronates.
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TBN improves motor function and prolongs survival in SOD1G93A and TDP-43M337V mouse model of amyotrophic lateral sclerosis 被引量:1
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作者 HUANG Chun-hui LI Jun +12 位作者 ZHANG Gui-liang LIN Ying-qi LI Cai-juan ZHENG Xiao SONG Xi-cheng HAN Bo-feng GUO Bao-jian TU Zhu-chi ZHANG Jun SUN Ye-wei WANG Yu-qiang YAN Sen ZHANG Zai-jun 《中国药理学与毒理学杂志》 CAS 北大核心 2021年第9期647-648,共2页
OBJECTIVE Amyotrophic lateral sclerosis(ALS)is a fatal neurodegenerative dis⁃ease characterized by progressive loss of upper and lower motor neurons that results in skeletal muscle atrophy,weakness and paralysis.Oxida... OBJECTIVE Amyotrophic lateral sclerosis(ALS)is a fatal neurodegenerative dis⁃ease characterized by progressive loss of upper and lower motor neurons that results in skeletal muscle atrophy,weakness and paralysis.Oxida⁃tive stress plays a key role in the pathogenesis of ALS,including familial forms of the disease arising from mutation of the gene coding for superoxide dismutase 1(SOD1).Moreover,although the pathogenesis of ALS is unclear,the abnormal accumulation of TAR DNA-binding pro⁃tein of 43 ku(TDP-43)is a pathological feature that exists in almost all patients.Thus far,there is no drug that can cure ALS/FTLD.Tetramethyl⁃pyrazine nitrone(TBN)is a derivative of tetra⁃methylapyrazine,derived from the traditional Chinese medicine Ligusticum chuanxiong,which has been widely proven to have therapeutic effects on models of various neurodegenerative diseases.TBN is currently under clinical investi⁃gation for several indications including a phaseⅡtrial of ALS.Here,we explored the therapeutic effect of TBN in the SOD1G93A and TDP-43M337V ALS mouse model.METHODS In the SOD1G93A transgenic mouse model,TBN was administered to mice by intraperitoneal or intragastric injection after the onset of motor deficits.At the same time,we unilaterally and bilaterally injected the TDP-43M337V virus into the striatum of the WT mouse,and gave the TBN treatment after the mice developed a phenotype.After administering these two models for a period of time,we con⁃ducted behavioral tests,including rotarod test,balance beam test,climbing pole test,etc,to evaluate the efficacy of TBN on SOD1G93A and TDP-43M337V models.Furthermore,we explored the possible mechanism of action of TBN in the treatment of ALS through Western blotting and immunohistochemistry/immunofluorescence staining analysis.RESULTS In the SOD1G93A transgenic mouse model,TBN slowed the pro⁃gression of motor neuron disease as evidenced by improved motor performance,reduced spinal motor neuron loss and the associated glial response,and decreased skeletal muscle fiber denervation and fibrosis.TBN treatment activated mitochondrial antioxidant activity through the PGC-1α/Nrf2/HO-1 pathway and decreased the expression of human SOD1.What′s more,in the TDP-43M337V mice model,the results showed that in mice with unilateral injection of TDP-43M337V,TBN improved motor deficits and cognitive im⁃pairment in the early stages of disease progres⁃sion.In mice with bilateral injection of TDP-43M337V into the striatum,TBN not only improved motor function but also prolonged survival rate.Moreover,we show that its therapeutic effect may be through activation of the Akt/mTOR/GSK-3βand AMPK/PGC-1α/Nrf2 signaling pathways.In summary,TBN is a promising agent for the treat⁃ment of ALS/FTLD.CONCLUSION TBN has shown good efficacy in both SOD1 and TDP-43 ALS-related models,and it may act by activating the AMPK/PGC-1α/Nrf2 signaling pathway,which shows some light for the development of ALS therapeutic drugs. 展开更多
关键词 amyotrophic lateral sclerosis tetra⁃methylpyrazine nitrone superoxide dismutase 1
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Analysis of the Composition and Physical and Mechanical Properties of Raw Materials for Thermal Insulation Fabrics 被引量:1
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作者 Juramirza Abdiramatovich Kayumov Matluba Nazarova +2 位作者 Bohodir Vohobjon Ogli Obilov Farhodjon Mahmudjonovich Dadaboyev Zuhra Yigitaliyevna Mamadaliyeva 《Engineering(科研)》 2021年第6期352-359,共8页
In this article, winter clothes, bedding, pillows, mattresses are produced in the Republic of Uzbekistan and used in the export products of foreign countries in domestic market shopping centers;existing nonwoven fabri... In this article, winter clothes, bedding, pillows, mattresses are produced in the Republic of Uzbekistan and used in the export products of foreign countries in domestic market shopping centers;existing nonwoven fabric samples were used as toys, children’s clothing as a heat retainer, a space-filler was selected on the basis of marketing survey analysis. Chemical bonding, processing technology, methods, linear density, thickness, air permeability, hygroscopicity, heat storage and heat transfer properties of the samples were analyzed experimentally based on the preparation methods, the fiber content was compared with the standard technology. The advantages and disadvantages of the samples were studied and recommendations for use in sewing according to consumer requirements were given. 展开更多
关键词 Sintepon (Origin Polyester Fiber) Sherstepon (Origin Wool + Polyester Fiber) Hollow Fiber POLYESTER Nitron Insulation Fabrics
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Benzisoxazole core and benzoxazolopyrrolidine via HDDA-derived benzyne with PTIO/DMPO
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作者 Yu Lei Wenjing Zhu +3 位作者 Yajuan Zhang Qiong Hu Jie Dong Yimin Hu 《Chinese Chemical Letters》 SCIE CAS CSCD 2023年第4期318-321,共4页
A novel method for HDDA-derived benzyne trapped by nitrone was developed.This research described a simple and efficient pathway for the synthesis of benzisoxazoles from arynes and PTIO(2-phenyl-4,4,5,5-tetramethylimid... A novel method for HDDA-derived benzyne trapped by nitrone was developed.This research described a simple and efficient pathway for the synthesis of benzisoxazoles from arynes and PTIO(2-phenyl-4,4,5,5-tetramethylimidazoline-3-oxide-1-oxyl),C-C and C-O bonds were formed in a single step without catalyst under mild conditions.The unexpected cleavage of C-N bond contributed to the formation of isoxazole ring,as indicated by DFT studies.Furthermore,we obtained the structure of benzoxazolopyrrolidine when the trapping agent is DMPO(5,5-dimethyl-1-pyrroline N-oxide). 展开更多
关键词 Benzisoxazole HDDA reaction BENZYNE NITRONE HETEROCYCLE
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THE REGIOSPECIFICITY OF INTRAMOLECULAR N-3-BUTENYL NITRONE CYCLOADDITION
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作者 Si Yu MA Xiao Yuan FU Department of Chemistry,Beijing Normal University,Beijing 100875 《Chinese Chemical Letters》 SCIE CAS CSCD 1991年第7期535-536,共2页
The reaction mechanism of the intramolecular cycloaddition of N-3-butenyl nitrone has been investigated theoretically by using AM1 MO method and transition state theory.There are two parallel reactions leading to two ... The reaction mechanism of the intramolecular cycloaddition of N-3-butenyl nitrone has been investigated theoretically by using AM1 MO method and transition state theory.There are two parallel reactions leading to two different regioisomers.The ratio of the rate constants of these two reactions was calculated to be 124.1(at 383.75 K).The obtained results can be used to explain the high regiospecificity of the reaction product. 展开更多
关键词 Pb 110 THE REGIOSPECIFICITY OF INTRAMOLECULAR N-3-BUTENYL NITRONE CYCLOADDITION TS
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Asymmetric 1,3-Dipolar Cycloaddition of the Chiral Nitronic Esters with Acrylate
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作者 Fu An KANG and Cheng Lie Ym(Department of Chemiscy Beijtw Normal Unthersho Beijing 100875) 《Chinese Chemical Letters》 SCIE CAS CSCD 1997年第12期0-0,共2页
Asymmetric 1,3-dipolar cycloaddihon of the chiral nitronic esters with acrylate giving the enantiomerically pure novel chiral bisheterocyclic compounds is describcd
关键词 Asymmetric 1 3-Dipolar Cycloaddition of the Chiral Nitronic Esters with Acrylate
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