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The Cycloaddition Reaction of Lawesson's Reagent with 1,3-Dienes
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作者 Liang Nian HE Ren Xi ZHUO(Department of Chemistry,Wuhan University,Wuhan, 430072) 《Chinese Chemical Letters》 SCIE CAS CSCD 1997年第8期655-656,共2页
Lawesson's reagent undergoes [2 + 4] cycloaddition reaction with 2-methyl-1, 3-butadiene,cyclopentadiene to yield heterocycles 4 and 5, respectively.
关键词 META OCH The Cycloaddition Reaction of lawesson’s reagent with 1 3-Dienes
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The Cyclization Reactions of Lawesson's Reagent with Bifunctional Substrates
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作者 Liang Nian HE Fei CAI +1 位作者 Xiang Hua QIN Kai LI(Institute of Organic Synthesis, Central China Normal University, Wuhan,430079) 《Chinese Chemical Letters》 SCIE CAS CSCD 1997年第9期751-754,共4页
The cyclizaion reactions of Lawesson's reagent(LR) with the substrates containing two functional groups such as hydroxy groups,amino groups, has been applied to prepare the O-P-O,N-P-N type 5-membered and 6-member... The cyclizaion reactions of Lawesson's reagent(LR) with the substrates containing two functional groups such as hydroxy groups,amino groups, has been applied to prepare the O-P-O,N-P-N type 5-membered and 6-membered phosphorus heterocycles.The heterocyclizaional possibility of LR with bifunctional compounds was also discussed. 展开更多
关键词 The Cyclization Reactions of lawesson’s reagent with Bifunctional substrates
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Lawesson试剂的环化反应 被引量:1
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作者 何良年 李凯 蔡飞 《华中师范大学学报(自然科学版)》 CAS CSCD 北大核心 1998年第1期61-65,共5页
综述了近10年来Lawesson试剂与含双官能团化合物的环化反应以及与不饱和化合物的环加成反应,并讨论了Lawesson试剂的环化反应在合成五元、六元磷杂环中的应用.
关键词 lawesson试剂 环化反应 杂环化合物 磷试剂
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Lawesson试剂在有机合成中的新应用 被引量:1
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作者 李玉桂 朱雪峰 周汉杰 《有机化学》 SCIE CAS CSCD 北大核心 1995年第5期461-474,共14页
本文评述了近十年来Lawesson试剂(LR)在有机合成尤其在杂环化合物合成中的新应用。
关键词 lawesson试剂 硫化 杂环化合物 评述
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具有生物活性的磷杂环化合物研究——ⅩⅣ.Lawesson试剂与含活泼氢的双官能团化合物的环化反应
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作者 何良年 李凯 +3 位作者 卓仁禧 刘小鹏 吴田捷 陆爱红 《化学学报》 SCIE CAS CSCD 北大核心 1999年第9期1026-1033,共8页
研究Lawesson试剂与含活泼氢的双官能团化合物的环化反应,合成了O-P-O,N-P-O,N-P-N型五元、六元及七元磷杂环.探讨了其成环可能性及其环化机理.初步的生物活性测定结果表明,应用Lawesson试剂所合成的磷杂环具有较好的选择性除草活性.
关键词 lawesson试剂 环化反应 磷杂环 除草活性 除草剂
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有机磷杂环化合物研究(Ⅷ)──Lawesson试剂与合两个氨基的底物的成环反应
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作者 何良年 陈茹玉 卓仁禧 《高等学校化学学报》 SCIE EI CAS CSCD 北大核心 1997年第12期1969-1973,共5页
研究Lawesson试剂与含有两个氨基的底物的成环反应,合成了N-P-N型五元、六元磷杂环3a-3b、sa-5b及8a-8b,并讨论了成环机理.初步的生测结果表明,所合成的磷杂环具有一定的除草活性,因此LR的成环反应是合成具有生物活性的磷杂环的... 研究Lawesson试剂与含有两个氨基的底物的成环反应,合成了N-P-N型五元、六元磷杂环3a-3b、sa-5b及8a-8b,并讨论了成环机理.初步的生测结果表明,所合成的磷杂环具有一定的除草活性,因此LR的成环反应是合成具有生物活性的磷杂环的新方法. 展开更多
关键词 试剂 磷杂环 成环反应 除草活性 有机磷
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Lawesson试剂硫化合成N,N′-二正丁基二硫代草酰胺
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作者 刘玮炜 纪延光 马卫兴 《农药》 CAS 北大核心 1997年第3期16-16,共1页
以Lawesson试剂与N,N-二正丁基草酰胺进行反应可制得N,N′-二正丁基二硫代草酰胺,且后处理简单,收率高。
关键词 试剂 正丁基 硫代草酰胺 合成 硫化
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Degradation of polyvinyl-alcohol wastewater by Fenton’s reagent: Condition optimization and enhanced biodegradability 被引量:12
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作者 肖羽堂 许双双 李志花 《Journal of Central South University》 SCIE EI CAS 2011年第1期96-100,共5页
The pretreatment of refractory polyvinyl-alcohol (PVA) wastewater with low value of CODcr by Fenton's reagent was investigated to enhance the biodegradabilily. The effects of operating conditions such as pH of the ... The pretreatment of refractory polyvinyl-alcohol (PVA) wastewater with low value of CODcr by Fenton's reagent was investigated to enhance the biodegradabilily. The effects of operating conditions such as pH of the solution, Fe2+ dosage, H2O2 dosage, reaction time and initial PVA concentration on the removal efficiency of CODCr were discussed. It is demonstrated that the optimum value of pH for removal of CODcr is 5 and the most suitable dosages of H2O2 (2%) and FeSO4 (10 mg/L) are 5% and 8.0%, respectively. When the initial CODcr value of the PVA water is 760 mg/L, the favorable reaction time is 110 min. Under these optimum conditions, the removal ratio of CODcr is 58.6% 61.4%, and the value of biodegradability (CODB/CODcr) increases markedly from 8.9% 9.7% to 62.6% 68.3%. 展开更多
关键词 Fenton's reagent POLYVINYL-ALCOHOL PRETREATMENT BIODEGRADABILITY
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化学抑制剂Woodward's Reagent K对来源于Erwinia rhapontici NX-5蔗糖异构酶的抑制动力学
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作者 王彦媛 李莎 +1 位作者 姚忠 徐虹 《生物加工过程》 CAS CSCD 2014年第6期62-66,95,共6页
从重组大肠杆菌E.coli BL21(p ET22b-palⅠ)中纯化得到来源于Erwinia rhapontici NX-5的蔗糖异构酶(sucrose isomerase,SIase,EC 5.4.99.11),以纯酶为对象考察其酶活力抑制动力学。结果表明:SIase纯比酶活1 512.77 U/mg,动力学常数Km=26... 从重组大肠杆菌E.coli BL21(p ET22b-palⅠ)中纯化得到来源于Erwinia rhapontici NX-5的蔗糖异构酶(sucrose isomerase,SIase,EC 5.4.99.11),以纯酶为对象考察其酶活力抑制动力学。结果表明:SIase纯比酶活1 512.77 U/mg,动力学常数Km=260 mmol/L,Vmax=39.41μmol/(L·s)。以化学抑制剂Woodward's Reagent K(WRK)对重组蔗糖异构酶进行抑制反应,反应体系中随着WRK浓度的升高,SIase与底物蔗糖的亲和力常数Km增大,最大反应速度Vmax在一定范围内保持稳定。通过对SIase的抑制动力学分析可得到,WRK对SIase的抑制类型为可逆的竞争性抑制,这可能与WRK与蔗糖的结构类似,与可竞争性的结合SIase的活性中心有关。 展开更多
关键词 蔗糖异构酶 抑制动力学 化学抑制剂Woodward′sreagentK
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Treatment of Wastewater Containing RDX by Fenton's Reagent 被引量:3
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作者 徐航 张东翔 徐文国 《Defence Technology(防务技术)》 SCIE EI CAS 2008年第1期18-21,共4页
Fenton's reagent was employed to treat the wastewater containing RDX.The effects of FeSO4 concentration,H2O2 concentration,pH value,reaction time,temperature and initial COD of wastewater on residual COD of wastew... Fenton's reagent was employed to treat the wastewater containing RDX.The effects of FeSO4 concentration,H2O2 concentration,pH value,reaction time,temperature and initial COD of wastewater on residual COD of wastewater were investigated.The results show that the optimum FeSO4 concentration and pH are 700 mg/L and 2.5,respectively,and the residual COD of wastewater decreases with the rise in H2O2 concentration,but increases with the rise in temperature.After Fenton's reagent treatment,the initial COD of less than 874 mg/L wastewater can meet effluent standard.Under conditions of 100 mg/L H2O2,437 mg/L initial COD and 15 ℃ temperature,the lowest residual COD is obtained at 83.80 mg/L in 5 min. 展开更多
关键词 氧化加工 锌基试剂 RDX 污水处理
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DCHA AS A NEW REAGENT FOR THE ESTERIFICATION OF OBSTINATED AMINO ACIDS BY THE MERRIFIELD'S RESIN 被引量:1
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作者 De Xin WANG Gui Shen LU (Institute of Materia Medica,Chinese Academy of Medical Sciences,Beijing 100050) 《Chinese Chemical Letters》 SCIE CAS CSCD 1991年第4期289-290,共2页
The obstinated amino acid,Boc-Asn(or Boc-Gln),was directly anchored onto the Merrifield's resin using DCHA as the base in present reaction.The yield(71.88%)of Boc-Asn-OCH_2-resin was much better than those(0-33.5%... The obstinated amino acid,Boc-Asn(or Boc-Gln),was directly anchored onto the Merrifield's resin using DCHA as the base in present reaction.The yield(71.88%)of Boc-Asn-OCH_2-resin was much better than those(0-33.5%)using Cs_2CO_3,KOH,KF.DEA and TEA as the base.which are efficient reagents for other amino acids in the same reaction. 展开更多
关键词 DEA TEA GLN DCHA As A NEW reagent FOR THE EsTERIFICATION OF OBsTINATED AMINO ACIDs BY THE MERRIFIELD’s REsIN As
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Degradation of Silicone Rubbers in Fenton's Reagents
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作者 吴凡 李克 +4 位作者 ZHANG Qinglian ZHANG Haining CHEN Yanan PAN Mu YAN Xinping 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2018年第4期793-796,共4页
Gaskets are applied in PEMFCs(proton exchange membrane fuel cells) to keep reactant gases and liquid within their respective regions, which are of great significance for the both sealing and electrochemical performa... Gaskets are applied in PEMFCs(proton exchange membrane fuel cells) to keep reactant gases and liquid within their respective regions, which are of great significance for the both sealing and electrochemical performance of fuel cells during the long-term operation. In this study, the degradation of silicone rubbers, often selected as seals in PEMFCs, in Fenton's reagents with different H_2O_2 concentrations was investigated. The changes in chemical properties, mechanical behavior and surface morphology of the samples were studied before and after exposure to the test environment over time. It is found that increasing H_2O_2 concentration will degrade the rubbers more severely. The experimental results elucidate the degradation mechanism of silicone rubbers in Fenton's reagents and the influence of H_2O_2 in the degradation process. 展开更多
关键词 silicone rubbers PEMFCs sEAL DEGRADATION Fenton's reagents
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Investigation of the Low Molecular Weight Thiol Composition in a Metastatic Prostate Cancer Cell Line (LNCaP) by LC-UV-MS and NMR after Labelling with the Ellman Reagent
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作者 Stephen Childs Nicolas Haroune +1 位作者 Lee Williams Michael Gronow 《American Journal of Analytical Chemistry》 2017年第1期1-18,共18页
The low molecular weight thiols present in the deproteinized extract of a prostate cancer cell line (LNCaP-FGC) were analysed after derivatization with the Ellman reagent (ESSE). The mixed disulphides formed (RSSE) we... The low molecular weight thiols present in the deproteinized extract of a prostate cancer cell line (LNCaP-FGC) were analysed after derivatization with the Ellman reagent (ESSE). The mixed disulphides formed (RSSE) were fractionated, characterized and quantified by liquid chromatography on a C-18 column using UV detection. This revealed the presence, in femtomoles per cell, of glutathione (8.30 ± 0.73), cysteine (2.71 ± 0.04) and cysteinylglycine (0.83 ± 0.10), accounting for the bulk of the thiol present. Further analysis of the cell extracts using a novel and sensitive mass spectrometry technique allowed the detection of low level of an additional derivative which was identified as cysteinylglycerate using NMRspectroscopy. 展开更多
关键词 Prostate Cancer Low Molecular Weight THIOLs THIOL Analysis Ultra-High Performance Liquid Chromatography Novel THIOL LC-Ms NMR Ellman’s reagent
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Use of Solid-Supported Reagents towards Synthesis of 2-Arylbenzoxazole, 3, 5-Diarylisoxazole and 1, 3, 5-Triarylpyrazole
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作者 Sneha Naik Vidya Desai 《Green and Sustainable Chemistry》 2013年第1期1-7,共7页
Herein we report a convenient and efficient synthesis of 2-Arylbenzoxazole from the Schiff’s bases of 2-Aminophenol, 3, 5-Diarylisoxazole from α, β-unsaturated ketoxime and 1,3,5-Triarylpyrazole from 2-pyrazoline a... Herein we report a convenient and efficient synthesis of 2-Arylbenzoxazole from the Schiff’s bases of 2-Aminophenol, 3, 5-Diarylisoxazole from α, β-unsaturated ketoxime and 1,3,5-Triarylpyrazole from 2-pyrazoline and N-Arylhydrazone by using milder, less toxic and less expensive-NBS-SiO2, KMnO4-Al2O3, PCC-SiO2 and ACC-Al2O3 as solid-supported oxidizing agents at room temperature. Within the framework of Green Chemistry, the use of solid supported reagents has many advantages such as 1) they are easy to remove from reactions by filtration 2) excess reagents can be used to drive the reaction without introducing any difficulties in purification 3) such solid-supported reagents react differently, mostly more selectively, than their unbound counterparts and 4) toxic, noxious and explosive chemicals are handled more safely when contained on solid support. 展开更多
关键词 schiff’s BAsEs 3 5-Diarylisoxazoles 2-ArylBenzoxazoles 1 5-Triaryl PYRAZOLEs solid-supported reagents
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Ellman’s试剂测定脱脂豆粕中巯基含量 被引量:11
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作者 田其英 谌卉 华欲飞 《食品与生物技术学报》 CAS CSCD 北大核心 2008年第6期107-110,共4页
采用3种不同方法对干热处理后的脱脂豆粕进行处理,再加入Ellman’s试剂来测定脱脂豆粕中的巯基含量。通过理论和数据分析得到,方法二即脱脂豆粕、尿素-SDS溶液和Ellman’s试剂相混合反应可用于测定脱脂豆粕中的巯基含量。
关键词 脱脂豆粕 Ellman’s试剂 巯基含量 方差分析
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泊马度胺的抗骨髓瘤细胞株MM1.S活性及对CRBN表达的影响 被引量:4
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作者 樊文静 范枝俏 +5 位作者 潘耀柱 杨柯 尹娇娇 赵宵晨 姚浩 白海 《中国实验血液学杂志》 CAS CSCD 北大核心 2019年第6期1907-1911,共5页
目的:探讨不同浓度泊马度胺对人多发性骨髓瘤细胞株MM1.S的作用及对CRBN表达的影响。方法:应用CCK-8法检测泊马度胺对MM1.S细胞增殖抑制作用;Annexin V-FITC/PI双染流式细胞术检测MM1.S细胞凋亡率;实时定量PCR检测CRBN基因表达水平;West... 目的:探讨不同浓度泊马度胺对人多发性骨髓瘤细胞株MM1.S的作用及对CRBN表达的影响。方法:应用CCK-8法检测泊马度胺对MM1.S细胞增殖抑制作用;Annexin V-FITC/PI双染流式细胞术检测MM1.S细胞凋亡率;实时定量PCR检测CRBN基因表达水平;Western blot法检测泊马度胺对MM1.S细胞CRBN蛋白表达的影响。结果:泊马度胺对MM1.S细胞具有抑制作用,其增殖抑制作用呈时间和剂量依赖性(r=0.981,r=0.990);泊马度胺能够诱导MM1.S细胞凋亡;浓度为0、40和80μmol/L的泊马度胺作用于MM1.S细胞72 h后,CRBN基因表达水平分别为:1.487±0.340,0.211±0.054和0.055±0.005;泊马度胺作用后,CRBN蛋白表达水平明显下降,差异均有统计学意义。结论:泊马度胺能够抑制MM1.S细胞增殖并促进其凋亡,一定浓度泊马度胺可降低MM1.S细胞CRBN基因表达并下调其蛋白表达水平。 展开更多
关键词 泊马度胺 Cereblon 骨髓瘤细胞株MM1.s 免疫调节剂
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由Law esson试剂合成2-硫代-1,3,2-二氮磷杂环戊-4-硫酮 被引量:1
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作者 李凯 何良年 +1 位作者 骆焱平 刘小鹏 《华中师范大学学报(自然科学版)》 CAS CSCD 北大核心 1999年第3期379-382,共4页
利用 Law esson 试剂和 α烷基氨基乙酰胺的环化反应合成了一类结构新颖的 1,3,2二氮磷杂环戊烷,对新化合物用元素分析, I R, N M R 和 M S进行了表征;以薄层色谱( T L C)监测反应进程并用色质联用(... 利用 Law esson 试剂和 α烷基氨基乙酰胺的环化反应合成了一类结构新颖的 1,3,2二氮磷杂环戊烷,对新化合物用元素分析, I R, N M R 和 M S进行了表征;以薄层色谱( T L C)监测反应进程并用色质联用( G C M S)分析了中间体的结构。 展开更多
关键词 lawesson试剂 二氮磷杂环戊烷 磷杂环戊硫酮
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(S)-2-氨基-1,1-二苯基-1-丙醇的合成和外消旋Droxidopa前体的拆分 被引量:3
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作者 张成刚 罗焕 +4 位作者 匡德忠 李鸿波 李蕾蕾 王海平 秦圣英 《化学研究与应用》 CAS CSCD 北大核心 2006年第2期165-168,共4页
(S)-2-氨基-1,1-二苯基-1-丙醇是一种合成多种手性助剂的重要中间体,也用于外消旋屈昔多巴前体化合物的拆分。从价廉易得的L-丙氨酸出发,通过四步反应制得,总收率55.6%L-丙氨酸经甲酯化,苄氧羰基保护制得的L-2-苄羰基氨基丙酸甲酯与苯... (S)-2-氨基-1,1-二苯基-1-丙醇是一种合成多种手性助剂的重要中间体,也用于外消旋屈昔多巴前体化合物的拆分。从价廉易得的L-丙氨酸出发,通过四步反应制得,总收率55.6%L-丙氨酸经甲酯化,苄氧羰基保护制得的L-2-苄羰基氨基丙酸甲酯与苯基溴化镁反应制得(S)-2-苄氧羰基氨基-1,1-二苯基-1-丙醇。是在5%Pd/C催化加氢下脱除苄氧羰基得到标题化合物。该制备方法涉及的中间体及目标化合物易于纯化,总收率高且重现性好。我们用制得的氨基醇能成功地拆分外消旋苏式屈昔多巴前体化合物3-3,4-二苄氧苯基)-N-苄氧羰基丙氨酸。 展开更多
关键词 拆分剂 (s)-2-胺基-1 1-二苯基-1-丙醇 Β-氨基醇 屈昔多巴
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Thionization Method of Glycosyl Urea and Carbamide Sugars 被引量:1
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作者 Baktygul Ernazarova Aida Bakirova +3 位作者 Asylkan Dzhumanazarova Zhypargul Abdullaeva Shamirbek Berkmamatov Gulsara Zhusupbaeva 《International Journal of Organic Chemistry》 2020年第3期111-122,共12页
This work is describing a thionization method for glycosyl urea and carbamide of sugars by using the Lawesson’s reagent. It is proposed the method based on the interaction of glycosyl urea and carbamide of sugars wit... This work is describing a thionization method for glycosyl urea and carbamide of sugars by using the Lawesson’s reagent. It is proposed the method based on the interaction of glycosyl urea and carbamide of sugars with the Lawessons reagent at a 1:1 ratio in the presence of a pyridine. As a result, sulfur-containing derivatives of sugar carbamides are obtained with the help of Lawesson’s reagent. Obtained experimental data are indicating the developed new method for thionization of sugar carbamides, which opens up broad possibilities for synthesis of various carbohydrate derivatives of thiourea. Significance of this work is that, thiourea derivatives are promising bactericidal, fungicidal and anti-inflammatory drugs. Therefore, the preparation of thiourea derivatives and the study of their properties remain topical tasks in the field of chemistry. 展开更多
关键词 Glycosyl Urea Glycosyl Thiourea synthesis lawesson’s reagent ANTI-INFLAMMATORY BACTERICIDAL Fungicidal Properties
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有机合成化学中新的构件——Japanese试剂 被引量:2
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作者 骆焱平 何良年 李凯 《化学试剂》 CAS CSCD 2000年第5期289-290,共2页
介绍了 Japanese试剂的制备、结构和化学反应。并就 Japanese试剂在有机合成中的应用加以概述。
关键词 Japanese试剂 氧-硫交换反应 环化反应 合成
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