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文章名     作者     期刊名     摘要     卷     期         如果没有找到您所需要的文献，请点击 ——此处申请     共57条记录   Discovery of Hypoiodite-Mediated Aminyl Radical Cyclization Lacking a Nitrogen Radical-Stabilizing Group: Application to Synthesis of an Oxazaspiroketal-Containing Cephalostatin Analog [作者：KOAG MYONG; LEE SEONGMIN,期刊：Organic Letters, 页码：4766-4769 , 文章类型： Article，,卷期：2011年13-18] Synthesis of an oxazaspiroketal-containing bissteroidal pyrazine is described. The key transformation of this synthesis involves stereoselective formation of oxazaspiroketal via aminyl-radical cyclization of primary amin... Peptide Ligations Accelerated by N-Terminal Aspartate and Glutamate Residues [作者：THOMAS GEMMA L; HSIEH YVES S Y; CHUN CANDY K Y; CAI ZHENGLI; REIMERS JEFFREY R; PAYNE RICHARD J,期刊：Organic Letters, 页码：4770-4773 , 文章类型： Article，,卷期：2011年13-18] A novel application of intramolecular base catalysis confers enhanced reaction rates for aminolysis ligations between peptide thioesters and peptides bearing N-terminal aspartate or glutamate residues. The broad scope of... Total Synthesis of (+/-)-Cylindricine C [作者：LAPOINTE GUILLAUME; SCHENK KURT; RENAUD PHILIPPE,期刊：Organic Letters, 页码：4774-4777 , 文章类型： Article，,卷期：2011年13-18] A concise synthesis of (+/-)-cylindricine C and its C(13)-epimer is described. Starting from 1-octyne, cylindricine C and 13-epi-cylindricine C were prepared in 11% and 15% yields, respectively. The synthesis involves th... Application of alpha-Alkoxy Bridgehead Radical for Coupling of Oxygenated Carbocycles [作者：URABE DAISUKE; YAMAGUCHI HIROKI; INOUE MASAYUKI,期刊：Organic Letters, 页码：4778-4781 , 文章类型： Article，,卷期：2011年13-18] A new coupling methodology for assembly of highly oxygenated carbocycles was developed. An alpha-alkoxy bridgehead radical was employed as the key reactive intermediate due to its potent reactivity, minimum steric intera... Cascade Reaction of Isatins with Heterocyclic Ketene Aminals: Synthesis of Imidazopyrroloquinoline Derivatives [作者：YU FUCHAO; YAN SHENGJIAO; HU LING; WANG YONGCHAO; LIN JUN,期刊：Organic Letters, 页码：4782-4785 , 文章类型： Article，,卷期：2011年13-18] A concise and efficient route for the synthesis of highly substituted imidazopyrroloquinoline derivatives by simply refluxing a reaction mixture of different types of isatins and heterocyclic ketene aminals (HKAs) by ace... Stereoselective Synthesis of F-Ring Saturated Estrone-Derived Inhibitors of Hedgehog Signaling Based on Cyclopamine [作者：ZHANG ZHIHUI; BAUBET VALERIE; VENTOCILLA CHRISTIAN; XIANG CHAOMEI; DAHMANE NADIA; WINKLER JEFFREY D,期刊：Organic Letters, 页码：4786-4789 , 文章类型： Article，,卷期：2011年13-18] Previous work in this laboratory established that the readily available F-ring aromatic analog of cyclopamine is a highly potent inhibitor of Hedgehog signaling. The synthesis and biological evaluation of two F-ring satu... Organocatalytic Iminium Ion/Carbene Reaction Cascade for the Formation of Optically Active 2,4-Disubstituted Cyclopentenones [作者：JACOBSEN CHRISTIAN BORCH; JENSEN KIM L; UDMARK JONAS; JORGENSEN KARL ANKER,期刊：Organic Letters, 页码：4790-4793 , 文章类型： Article，,卷期：2011年13-18] An organocatalytic iminium ion/N-heterocyclic carbene (NHC) cascade reaction between beta-keto phenyltetrazolesulfones and alpha,beta-unsaturated aldehydes, providing direct access to optically active 2,4-disubstituted c... Nickel-Catalyzed Tetramerization of Alkynes: Synthesis and Structure of Octatetraenes [作者：WU TSUNCHENG; CHEN JHENGJHIH; WU YAOTING,期刊：Organic Letters, 页码：4794-4797 , 文章类型： Article，,卷期：2011年13-18] In the presence of a catalytic system comprised of NiBr(2)(dppe) and Zn, arylacetylenes undergo tetramerization to form linear octatetraenes, generally in good to excellent yields. The structure of the coupling products ... Jasisoquinolines A and B, Architecturally New Isoquinolines, from a Marine Sponge Jaspis sp. [作者：IMAE YASUFUMI; TAKADA KENTARO; MURAYAMA SHUHEI; OKADA SHIGERU; ISE YUJI; MATSUNAGA SHIGEKI,期刊：Organic Letters, 页码：4798-4801 , 文章类型： Article，,卷期：2011年13-18] Two architecturally new isoquinolines, jasisoquinolines A and B, were isolated from a marine sponge Jaspis sp. as cathepsin B inhibitors. Their structures were determined by a combination of spectroscopic analyses and ch... Palladium(II)-Catalyzed Direct Alkoxylation of Arenes: Evidence for Solvent-Assisted Concerted Metalation Deprotonation [作者：ANAND MEGHA; SUNOJ RAGHAVAN B,期刊：Organic Letters, 页码：4802-4805 , 文章类型： Article，,卷期：2011年13-18] Density functional theory investigations on the mechanism of palladium acetate catalyzed direct alkoxylation of N-methoxybenzamide in methanol reveal that the key steps involve solvent-assisted N-H as well as C-H bond ac... One-Step Preparation of Functionalized (E)-Vinylsilanes from Aldehydes [作者：LIM DIANE S W; ANDERSON EDWARD A,期刊：Organic Letters, 页码：4806-4809 , 文章类型： Article，,卷期：2011年13-18] Functionalized (E)-vinylsilanes have been prepared in one step from a wide range of aldehydes, via a chromium(II)-mediated olefination with novel dihalomethylsilane reagents, in moderate to excellent yields and with exce... Total Synthesis of (+)-Lysergic Acid [作者：LIU QIANG; JIA YANXING,期刊：Organic Letters, 页码：4810-4813 , 文章类型： Article，,卷期：2011年13-18] A stereocontrolled total synthesis of (+)-lysergic acid (1) is achieved using three metal-catalyzed methodologies for the construction of three key rings. Highlights of the synthesis include Pd-catalyzed indole synthesis... [3+2] Coupling of Quinone Monoacetals by Combined Acid-Hydrogen Bond Donor [作者：DOHI TOSHIFUMI; HU YINJUN; KAMITANAKA TOHRU; WASHIMI NAOHIKO; KITA YASUYUKI,期刊：Organic Letters, 页码：4814-4817 , 文章类型： Article，,卷期：2011年13-18] The expeditious and efficient [3 + 2] coupling approach of quinone monoacetals 1 with alkene nucleophiles 2 by the action of an activated Bronsted acid in the presence of a hydrogen bond donor perfluorinated alcohol has ... Formation of a Cyclic Dimer Containing Two Mirror Image Monomers in the Solid State Controlled by van der Waals Forces [作者：ZHANG ZIBIN; YU GUOCAN; HAN CHENGYOU; LIU JIYONG; DING XIA; YU YIHUA; HUANG FEIHE,期刊：Organic Letters, 页码：4818-4821 , 文章类型： Article，,卷期：2011年13-18] Two new copillar[5]arenes were prepared. They are arranged in two completely different motifs, a cyclic dimer containing two monomers with two different conformations that are mirror images of each other and linear supra... Chiral Phosphoric Acid-Catalyzed Addition of Thiols to N-Acyl Imines: Access to Chiral N,S-Acetals [作者：INGLE GAJENDRASINGH K; MORMINO MICHAEL G; WOJTAS LUKASZ; ANTILLA JON C,期刊：Organic Letters, 页码：4822-4825 , 文章类型： Article，,卷期：2011年13-18] The first catalytic asymmetric method to prepare enantioenriched N,S-acetals using chiral BINOL phosphoric acids is reported. The reaction combines N-acyl imines with thiols to generate products in excellent yield and en... Kinetics of the Oxidation of Quercetin by 2,2-Diphenyl-1-picrylhydrazyl (dpph(center dot)) [作者：FOTI MARIO C; DAQUINO CARMELO; DILABIO GINO A; INGOLD K U,期刊：Organic Letters, 页码：4826-4829 , 文章类型： Article，,卷期：2011年13-18] In methanol/water, dpph(center dot) bleaching (519 nm) by quercetin, QH(2), exhibits biphasic kinetics. The dpph(center dot) reacts completely with the quercetin anion within 100 ms. Subsequent slower bleaching involves ...