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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53条记录   Application of a Domino Friedel-Crafts Acylation/Alkylation Reaction to the Formal Syntheses of (?-Taiwaniaquinol B and (?-Dichroanone. [作者：Tang, Shouchu;Xu, Yanfen;He, Jinmei;He, Yongping;Zheng, Jiyue;Pan, Xinfu;She, Xuegong;,期刊：Organic Letters, 页码：1855-1858 , 文章类型： 研究论文，,卷期：2008年10-9] An efficient acid-promoted domino Friedel-Crafts (FC) acylation/alkylation reaction has been developed for the construction of the core 6,5,6-ABC tricyclic skeleton (e.g. I) of taiwaniaquinoids. The formal total synthes... Efficient and Divergent Synthesis of Fully Substituted 1H-Pyrazoles and Isoxazoles from Cyclopropyl Oximes. [作者：Wang, Kewei;Xiang, Dexuan;Liu, Jinying;Pan, Wei;Dong, Dewen;,期刊：Organic Letters, 页码：1691-1694 , 文章类型： 研究论文，,卷期：2008年10-9] Efficient and divergent one-pot synthesis of fully substituted 1H-pyrazoles and isoxazoles from cyclopropyl oximes based on reaction conditions selection is reported. Under Vilsmeier conditions (POCl3/DMF), substituted ... Synthesis of Homochiral Dihydroxy-4-nitroisoxazolines via One-Pot Asymmetric Dihydroxylation-Reduction. [作者：Adamo, Mauro F. A.;Nagabelli, Murali;,期刊：Organic Letters, 页码：1807-1810 , 文章类型： 研究论文，,卷期：2008年10-9] A one-pot procedure to prep. a family of homochiral dihydroxy-4-nitroisoxazolines, e.g., I, is disclosed. This new methodol. affords the title compds. in good yields, excellent enantiopurity, and without the use of chro... Nitrogen-Directed Ortho-Selective Homocoupling of Aromatic Compounds Catalyzed by Ruthenium Complexes. [作者：Oi, Shuichi;Sato, Hitoshi;Sugawara, Shoko;Inoue, Yoshio;,期刊：Organic Letters, 页码：1823-1826 , 文章类型： 研究论文，,卷期：2008年10-9] A nitrogen-directed regioselective homocoupling reaction of arom. compds. has been found to be catalyzed by a ruthenium complex in the presence of methallyl acetate as a hydrogen scavenger. E.g., in presence of [RuCl2(c... Ir-Catalyzed Regio- and Enantioselective Friedel-Crafts-Type Allylic Alkylation of Indoles. [作者：Liu, Wen-Bo;He, Hu;Dai, Li-Xin;You, Shu-Li;,期刊：Organic Letters, 页码：1815-1818 , 文章类型： 研究论文，,卷期：2008年10-9] Highly regio- and enantioselective Ir-catalyzed Friedel-Crafts type allylic alkylation of indoles have been realized using [Ir(COD)Cl]2/phosphoramidite ligand, affording the branched products, e.g., I, with up to >97/3 b... Diastereoselective Brook Rearrangement-Mediated [3 + 4] Annulation: Application to a Formal Synthesis of (+)-Laurallene. [作者：Sasaki, Michiko;Hashimoto, Azusa;Tanaka, Koudai;Kawahata, Masatoshi;Yamaguchi, Kentaro;Takeda, Kei;,期刊：Organic Letters, 页码：1803-1806 , 文章类型： 研究论文，,卷期：2008年10-9] The formal synthesis of (+)-laurallene, a halogenated eight-membered ring ether, was accomplished. The synthesis involves construction of a trans a,a'-disubstituted oxocene structure through a Brook rearrangement-mediat... Synthetic Studies on Maitotoxin. 3. Stereoselective Synthesis of the BCDE-Ring System. [作者：Satoh, Masanori;Koshino, Hiroyuki;Nakata, Tadashi;,期刊：Organic Letters, 页码：1683-1685 , 文章类型： 研究论文，,卷期：2008年10-9] The stereoselective synthesis of the BCDE-ring system I of maitotoxin has been accomplished through a two-directional strategy for the construction of polycyclic ether. The key reactions involve SmI2-induced double cycl... Synthetic Studies on Maitotoxin. 2. Stereoselective Synthesis of the WXYZA'-Ring System. [作者：Morita, Masayuki;Haketa, Tasuku;Koshino, Hiroyuki;Nakata, Tadashi;,期刊：Organic Letters, 页码：1679-1682 , 文章类型： 研究论文，,卷期：2008年10-9] The stereoselective synthesis of the WXYZA'-ring system I of maitotoxin has been accomplished via a linear synthetic approach, in which key reactions were SmI2-induced cyclization of b-alkoxyacrylate for the construction... Synthetic Studies on Maitotoxin. 1. Stereoselective Synthesis of the C'D'E'F'-Ring System Having a Side Chain. [作者：Morita, Masayuki;Ishiyama, Seishi;Koshino, Hiroyuki;Nakata, Tadashi;,期刊：Organic Letters, 页码：1675-1678 , 文章类型： 研究论文，,卷期：2008年10-9] The stereoselective synthesis of the maitotoxin C'D'E'F'-ring system I having a side chain has been accomplished through a convergent strategy. The key reactions include Horner-Wadsworth-Emmons coupling of the C'D'E'-ri... Efficient Intermolecular Iron-Catalyzed Amidation of C-H Bonds in the Presence of N-Bromosuccinimide. [作者：Wang, Zhe;Zhang, Yongming;Fu, Hua;Jiang, Yuyang;Zhao, Yufen;,期刊：Organic Letters, 页码：1863-1866 , 文章类型： 研究论文，,卷期：2008年10-9] system was developed that efficiently promotes amidation of benzylic sp3 C-H bonds in Et acetate under mild conditions. Thus, reaction of Ph2CH2 with PhCONH2 in EtOAc contg. FeCl2 and N-bromosuccinimide at 50?for six ho... Asymmetric Nitroaldol Reaction Catalyzed by a C2-Symmetric Bisoxazolidine Ligand. [作者：Liu, Shuanglong;Wolf, Christian;,期刊：Organic Letters, 页码：1831-1834 , 文章类型： 研究论文，,卷期：2008年10-9] A C2-sym. bisoxazolidine catalyzed the asym. Henry reaction of aliph. and arom. aldehydes to yield b-hydroxy nitroalkanes in up to 99% yield and 95% ee. The bisoxazolidine-catalyzed nitroaldol formation requires relativ... Hexafluoroisopropanol as a Unique Solvent for Stereoselective Iododesilylation of Vinylsilanes. [作者：Ilardi, Elizabeth A.;Stivala, Craig E.;Zakarian, Armen;,期刊：Organic Letters, 页码：1727-1730 , 文章类型： 研究论文，,卷期：2008年10-9] Stereoselective prepn. of iodoalkenes from vinylsilanes is described. 1,1,1,3,3,3-Hexafluoroisopropanol serves as a unique solvent that ensures high yields and stereoselectivities in the iododesilylation of a variety of ... Expedient Synthesis of the Tetracyclic Core of ent-Nakadomarin A. [作者：Deng, Haibing;Yang, Xiaobao;Tong, Zhaolong;Li, Zhong;Zhai, Hongbin;,期刊：Organic Letters, 页码：1791-1793 , 文章类型： 研究论文，,卷期：2008年10-9] An efficient eight-step assembly of the tetracyclic core (ABCD rings), I, of ent-(+)-nakadomarin A, a bioactive hexacyclic marine alkaloid, has been realized with Sonogashira coupling, platinum(II)-promoted cascade cycli... Synthesis of bicyclo[3.1.0]hexane derivatives as conformationally restricted analogues of b-arabinofuranosyl and a-galactofuranosyl rings. [Erratum to document cited in CA148:331928]. [作者：Li, Jing;Lowary, Todd L.;,期刊：Organic Letters, 页码：1879-1879 , 文章类型： 研究论文，,卷期：2008年10-9] On page 884, in Ref. 21, the authors failed to cite previous work by Bennet and co-workers, which has demonstrated that amino derivs. of bicyclo [4.1.0]heptanes are potent glycosidase inhibitors. The ref. should include... Fluorescent Amino- and Thiopyronin Dyes. [作者：Wu, Liangxing;Burgess, Kevin;,期刊：Organic Letters, 页码：1779-1782 , 文章类型： 研究论文，,卷期：2008年10-9] Highly fluorescent rhodamine/rosamine analogs (I) (Nu = NR2, NHR, or SCH2Ph; X = H or CO2Me) were prepd. from ketone (II). A direct route to novel heteroatom analogs of rhodamine and rosamine systems is described here. ... Distinctive circular dichroism signature for 14-helix-bundle formation by b-peptides. [作者：Pomerantz, William C.;Grygiel, Tami L. R.;Lai, Jonathan R.;Gellman, Samuel H.;,期刊：Organic Letters, 页码：1799-1802 , 文章类型： 研究论文，,卷期：2008年10-9] We identify a distinctive CD (CD) signature for self-assembled 14-helical b-peptides. Our data show that self-assembly leads to a mimimum at 205 nm, which is distinct from the well-known min. at 214 nm for a monomeric 1...