个性化文献订阅>文章检索

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   Photomodulated chiral induction in helical azobenzene oligomers. [作者：King, Eric D.;Tao, Peng;Sanan, Toby T.;Hadad, Christopher M.;Parquette, Jon R.;,期刊：Organic Letters, 页码：1671-1674 , 文章类型： 研究论文，,卷期：2008年10-9] Appending L-alanine to the terminal positions of a helical azobenzene oligomer produced a P helical bias, which increased with oligomer length. Irradn. gave rise to E ?Z isomerization of the terminal azo linkages, which... A Cation-Directed Switch of Intermolecular Spin-Spin Interaction of Guanosine Derivatives Functionalized with Open-Shell Units. [作者：Graziano, Carla;Masiero, Stefano;Pieraccini, Silvia;Lucarini, Marco;Spada, Gian Piero;,期刊：Organic Letters, 页码：1739-1742 , 文章类型： 研究论文，,卷期：2008年10-9] The guanosine deriv. functionalized with the persistent radical unit 4-carbonyl-2,2,6,6-tetramethylpiperidin-1-oxyl in soln. has no particular intermol. spin-spin interactions; however, in the presence of potassium ions ... One-Pot Synthesis of Nucleoside 5'-Triphosphates from Nucleoside 5'-H-Phosphonates. [作者：Sun, Qi;Edathil, Jocelyn P.;Wu, Runzhi;Smidansky, Eric D.;Cameron, Craig E.;Peterson, Blake R.;,期刊：Organic Letters, 页码：1703-1706 , 文章类型： 研究论文，,卷期：2008年10-9] Nucleoside 5'-triphosphates (NTPs) play key roles in biol. and medicine. However, these compds. are notoriously difficult to synthesize. We describe a one-pot method to prep. NTPs from nucleoside 5'-H-phosphonate mono-... Utilization of a Michael Addition: Dipolar Cycloaddition Cascade for the Synthesis of (?-Cylindricine C. [作者：Flick, Andrew C.;Caballero, Maria Jose Arevalo;Padwa, Albert;,期刊：Organic Letters, 页码：1871-1874 , 文章类型： 研究论文，,卷期：2008年10-9] A new approach to the marine alkaloid (?-cylindricine C (I) has been devised. The key element of the synthesis consists of a Michael addn./dipolar cycloaddn. cascade between 2,3-bis(phenylsulfonyl)-1,3-butadiene and 9-t... First Total Synthesis of (-)-Achilleol B: Reassignment of Its Relative Stereochemistry. [作者：Arteaga, Jesus F.;Domingo, Victoriano;Quilez del Moral, Jose F.;Barrero, Alejandro F.;,期刊：Organic Letters, 页码：1723-1726 , 文章类型： 研究论文，,卷期：2008年10-9] The first total synthesis of (-)-achilleol B (I) was achieved using a convergent approach with a longest linear sequence of 14 steps. Three key steps were employed, including an enantioselective Robinson annelation for t... Desymmetrization of Metalated Cyclohexadienes with Chiral N-tert-Butanesulfinyl Imines. [作者：Maji, Modhu Sudan;Frohlich, Roland;Studer, Armido;,期刊：Organic Letters, 页码：1847-1850 , 文章类型： 研究论文，,卷期：2008年10-9] This communication describes the desymmetrization of various achiral metalated cyclohexadienes with chiral N-tert-butanesulfinyl imines. Depending on the metal used, either the sym. diene (dicyclohexadienyl-Zn) or the de... Rhodium-Catalyzed Borylative Cyclization of 2-Alkynylaryl Isocyanates with Bis(pinacolato)diboron. [作者：Miura, Tomoya;Takahashi, Yusuke;Murakami, Masahiro;,期刊：Organic Letters, 页码：1743-1745 , 文章类型： 研究论文，,卷期：2008年10-9] 2-Alkynylaryl isocyanates reacted with bis(pinacolato)diboron in the presence of a cationic Rh(I) catalyst to produce borylated 3-alkylideneoxindoles stereoselectively. The C-B linkage formed was further transformed via... Oxidative Amination of Cuprated Pyrimidine and Purine Derivatives. [作者：Boudet, Nadege;Dubbaka, Srinivas Reddy;Knochel, Paul;,期刊：Organic Letters, 页码：1715-1718 , 文章类型： 研究论文，,卷期：2008年10-9] Compounds (More Than One Hetero Atom)) Section Using regioselective cuprations (via magnesiations), various primary, secondary and tertiary aminated pyrimidine and purine derivs., e.g. I and II, were prepd. by the oxidat... Efficient Phosphonium-Mediated Synthesis of 2-Amino-1,3,4-oxadiazoles. [作者：Levins, Christopher G.;Wan, Zhao-Kui;,期刊：Organic Letters, 页码：1755-1758 , 文章类型： 研究论文，,卷期：2008年10-9] An efficient room temp. procedure for the prepn. of 2-amino-1,3,4-oxadiazoles is disclosed. Oxadiazol-2-ones can be activated for SNAr substitution using phosphonium reagents (e.g., BOP). This approach provides conveni... Dimethyl Sulfide Induced [3 + 2] Annulation Strategy: An Efficient Synthesis of Functionalized Dihydropyrazole Derivatives Using the Baylis-Hillman Bromides. [作者：Basavaiah, Deevi;Roy, Suparna;,期刊：Organic Letters, 页码：1819-1822 , 文章类型： 研究论文，,卷期：2008年10-9] Baylis-Hillman bromides have been successfully employed as a valuable source of 1,3-dipoles for cycloaddn. onto dialkyl azodicarboxylates (dipolarophiles) under the influence of di-Me sulfide and potassium carbonate to p... Pd-Catalyzed Carboetherification of b,g-Unsaturated Oximes: A Novel Approach to D2-Isoxazolines. [作者：Jiang, Dahong;Peng, Jinsong;Chen, Yuanwei;,期刊：Organic Letters, 页码：1695-1698 , 文章类型： 研究论文，,卷期：2008年10-9] A novel route to the synthesis of D2-isoxazoline derivs. is described. Reaction of b,g-unsatd. oximes with aryl bromides via palladium-catalyzed carboetherification affords 3,5-disubstituted D2-isoxazolines, e.g., I, in ... Palladium-Catalyzed sp3 C-H Activation of Simple Alkyl Groups: Direct Preparation of Indoline Derivatives from N-Alkyl-2-bromoanilines. [作者：Watanabe, Toshiaki;Oishi, Shinya;Fujii, Nobutaka;Ohno, Hiroaki;,期刊：Organic Letters, 页码：1759-1762 , 文章类型： 研究论文，,卷期：2008年10-9] The sp3 C-H activation of a simple alkyl group catalyzed by palladium(0) provides a novel and convenient strategy for the synthesis of various indolines, e.g., I, from simple precursors, such as N-alkyl-2-bromoanilines. ... Synthesis of (2-Oxoindolin-3-ylidene)methyl Acetates Involving a C-H Functionalization Process. [作者：Tang, Shi;Peng, Peng;Wang, Zhi-Qiang;Tang, Bo-Xiao;Deng, Chen-Liang;Li, Jin-Heng;Zhong, Ping;Wang, Nai-Xing;,期刊：Organic Letters, 页码：1875-1878 , 文章类型： 研究论文，,卷期：2008年10-9] A novel palladium-catalyzed oxidative C-H functionalization protocol for the synthesis of (2-oxoindolin-3-ylidene)methyl acetates has been developed. In the presence of Pd(OAc)2 and PhI(OAc)2, a variety of N-arylpropiol... Palladium-Catalyzed Perarylation of 3-Thiophene- and 3-Furancarboxylic Acids Accompanied by C-H Bond Cleavage and Decarboxylation. [作者：Nakano, Masaya;Tsurugi, Hayato;Satoh, Tetsuya;Miura, Masahiro;,期刊：Organic Letters, 页码：1851-1854 , 文章类型： 研究论文，,卷期：2008年10-9] 3-Thiophene- and 3-furancarboxylic acids efficiently undergo perarylation accompanied by cleavage of the three C-H bonds and decarboxylation upon treatment with excess aryl bromides in the presence of a palladium catalys... Modular Synthesis of the C9-C27 Degradation Product of Aflastatin A via Alkyne-Epoxide Cross-Couplings. [作者：Robles, Omar;McDonald, Frank E.;,期刊：Organic Letters, 页码：1811-1814 , 文章类型： 研究论文，,卷期：2008年10-9] A modular approach to the synthesis of complex polyketide natural products is demonstrated for the synthesis of the C9-C27 degrdn. product I from aflastatin A. The product of the cross-coupling of C23-C27 terminal alkyn... Second-Generation Total Synthesis of Haterumalide NA Using B-Alkyl Suzuki-Miyaura Coupling. [作者：Hayakawa, Ichiro;Ueda, Mitsuru;Yamaura, Masashi;Ikeda, Yoichi;Suzuki, Yuta;Yoshizato, Kensaku;Kigoshi, Hideo;,期刊：Organic Letters, 页码：1859-1862 , 文章类型： 研究论文，,卷期：2008年10-9] Second-generation total synthesis of haterumalide NA I, a potent cytotoxic marine macrolide, was achieved by using B-alkyl Suzuki-Miyaura coupling and Nozaki-Hiyama-Kishi coupling as key steps (1.2% in 33 steps). Compar...