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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63条记录   Asymmetric Dieckmann condensation via memory of chirality: synthesis of the key intermediate for AS-3201, an aldose reductase inhibitor. [作者：Watanabe, Toshihide;Kawabata, Takeo;,期刊：Heterocycles, 页码：1593-1606 , 文章类型： 研究论文，,卷期：2008年76-2] Asym. Dieckmann condensation via memory of chirality was developed. A key intermediate, succinimide I, for the synthesis of AS-3201, an aldose reductase inhibitor, was prepd. in 94% ee by asym. Dieckmann condensation of... Asymmetric hetero Diels-Alder reaction of nitroso compounds utilizing tartaric acid ester as a chiral auxiliary. [作者：Sakai, Hiroki;Ding, Xia;Yoshida, Tetsusuke;Fujinami, Shuhei;Ukaji, Yutaka;Inomata, Katsuhiko;,期刊：Heterocycles, 页码：1285-1300 , 文章类型： 研究论文，,卷期：2008年76-2] The regio- and enantioselective hetero Diels-Alder reaction of a nitroso compd. with a cyclic dienol, cyclohexa-1,3-dienemethanol, was realized utilizing a stoichiometric amt. of tartrate as a chiral auxiliary to afford ... Enantioselective synthesis of both enantiomers of etodolac via a lipase-catalyzed kinetic resolution. [作者：Akai, Shuji;Nemoto, Hiroyuki;Egi, Masahiro;,期刊：Heterocycles, 页码：1537-1547 , 文章类型： 研究论文，,卷期：2008年76-2] The efficient prepn. of both enantiomers of etodolac was achieved by lipase-catalyzed kinetic resoln. of the corresponding racemic primary alc. followed by chemoselective oxidn. Synthesis, structure, and properties of 2,5,8,11,14,17-hexamethyltriphenyleno[2,1-b:3,4-b':6,5-b'':7,8-b''':10,9- b'''':11,12-b''''']hexathiophene. [作者：Endou, Masaru;Ie, Yutaka;Aso, Yoshio;,期刊：Heterocycles, 页码：1043-1048 , 文章类型： 研究论文，,卷期：2008年76-2] b'''':11,12-b''''']hexathiophene I was synthesized by Fe(III)-mediated oxidative cyclization of hexakis(2-methyl-4-thienyl)benzene, and its structure was detd. by x-ray crystallog. anal. [triclinic, space group P-1, a 8.... Fluorous thiazolium salts for the intramolecular Stetter reaction. [作者：Hara, Osamu;Kume, Atsuko;Sugiura, Michiharu;Maeba, Isamu;,期刊：Heterocycles, 页码：1027-1031 , 文章类型： 研究论文，,卷期：2008年76-2] The fluorous thiazolium salt I derived from 4-methyl-5-thiazoleethanol was employed for an intramol. Stetter reaction. The catalytic activity of the fluorous catalyst I was similar to that of the std. catalyst. The flu... Asymmetric synthesis of the antiepileptic drug levetiracetam. [作者：Imahori, Tatsushi;Omoto, Keisuke;Hirose, Yumi;Takahata, Hiroki;,期刊：Heterocycles, 页码：1627-1632 , 文章类型： 研究论文，,卷期：2008年76-2] Palladium-catalyzed asym. synthesis of levetiracetam of antiepileptic drug was expediently accomplished through a dynamic kinetic asym. transformation (DYKAT) of succinimide with butadiene monoepoxide. Free radical tandem addition-cyclization of Te-phenyl N,N-dimethylcarbamotelluroate to 1,6-enynes. [作者：Fujiwara, Shin-ichi;Shimizu, Yoshihiko;Makita, Yoshimasa;Shin-ike, Tsutomu;Kambe, Nobuaki;,期刊：Heterocycles, 页码：1577-1584 , 文章类型： 研究论文，,卷期：2008年76-2] Radical tandem addn. of Me2NC(O)TePh (I) to alkenes and alkynes was examd. Simple addn. of I to alkenes such as styrene and acrylate did not take place under irradn. of visible light. However, when alkynes were added t... Triphenylphosphoranylidene substituted heterocycles as versatile intermediates. [作者：Katritzky, Alan R.;Vincek, Adam S.;Steel, Peter J.;,期刊：Heterocycles, 页码：1401-1423 , 文章类型： 研究论文，,卷期：2008年76-2] N-Cbz-(a-aminoacyl)benzotriazoles reacted with (stabilized-methylene)triphenylphosphoranes to give the corresponding esters (66-91%) or nitriles (63-85%). Deprotection of N-Cbz-g-amino-b-oxo-a-triphenylphosphoranylidene... Rhodium-catalyzed intramolecular cycloaddition of cyclopropene-ynes triggered by carbon-carbon bond cleavage. [作者：Shibata, Takanori;Maekawa, Shunsuke;Tamura, Kohei;,期刊：Heterocycles, 页码：1261-1270 , 文章类型： 研究论文，,卷期：2008年76-2] In the presence of a catalytic amt. of RhCl(PPh3)3, an intramol. cycloaddn. of cyclopropene-yne proceeded along with C-C bond cleavage of the cyclopropene ring to give various bicyclic cyclopentadiene derivs. in good to ... Novel substituted tetrathia[7]helicenes by direct functionalization of the helical system or photocyclization of substituted 1,2-(bis-benzodithienyl)ethenes. [作者：Rigamonti, Clara;Ticozzelli, Maria Teresa;Bossi, Alberto;Licandro, Emanuela;Giannini, Clelia;Maiorana, Stefano;,期刊：Heterocycles, 页码：1439-1470 , 文章类型： 研究论文，,卷期：2008年76-2] The synthesis of several tetrathia[7]helicenes functionalized with different electron-donor and electron-acceptor substituents in the positions 2,13 (the a positions of terminal thiophene rings) and/or 7,8 (on the centra... Influence of the position of tert-butyl substituents on reactivity of quinone dimers yielding dibenzofuran-1,4-diones. [作者：Hayashi, Naoto;Kanda, Akifumi;Higuchi, Hiroyuki;Ninomiya, Keiko;,期刊：Heterocycles, 页码：1361-1367 , 文章类型： 研究论文，,卷期：2008年76-2] Reactivity of two isomeric quinone dimers, 5,5'- (I) and 6,6'-di-tert-butyl-2,2'-bisbenzoquinone (II) were compared. Both quinone dimers underwent thermal cyclization in EtOH to give dibenzofuran-1,4-diones exclusively,... Epimerization of trans-3-arylaziridine-2-carboxylates at the C3 position. [作者：Kumamoto, Takuya;Nagayama, Shiin-ichiro;Hayashi, Yukiko;Kojima, Hiroaki;David, Lemin;Nakanishi, Waka;Ishikawa, Tsutomu;,期刊：Heterocycles, 页码：1155-1170 , 文章类型： 研究论文，,卷期：2008年76-2] An effective trans to cis epimerization of 1-benzyl-3-arylaziridine-2-carboxylates is described. The combination of Sm metal, I2, and Me2N(CH2)2OH promoted the epimerization of the trans isomer to a cis and trans mixt. ... Synthesis of substituted aziridines via intramolecular reactions of b-N-chloroethylamino carbanions. [作者：Makosza, Mieczyslaw;Bobryk, Karolina;Krajewski, Dariusz;,期刊：Heterocycles, 页码：1511-1524 , 文章类型： 研究论文，,卷期：2008年76-2] Simple and efficient method of synthesis of 2-alkoxycarbonyl-, 2-cyano-, and 2-phenylsulfonyl-N-alkylaziridines was elaborated via intramol. nucleophilic substitution of Cl in N-chloro-2-alkoxycarbonyl(cyano, phenylsulfo... Asymmetric epoxidation of a,b-unsaturated ketones with hydrogen peroxide catalyzed by axially chiral guanidine base. [作者：Terada, Masahiro;Nakano, Megumi;,期刊：Heterocycles, 页码：1049-1055 , 文章类型： 研究论文，,卷期：2008年76-2] The enantioselective epoxidn. of a,b-unsatd. ketones with H2O2 was demonstrated using axially chiral guanidine as a base catalyst. H2O2 can be utilized as a cost-effective and atom-efficient oxidant in the present catal... A convenient synthesis of optically active biopterin. [作者：Shiro, Yuichi;Urano, Fumi;Kuroda, Yasuhiro;Murata, Shizuaki;,期刊：Heterocycles, 页码：1329-1335 , 文章类型： 研究论文，,卷期：2008年76-2] Naturally occurring L-erythro-biopterin is synthesized using regioselective pteridine-ring formation from a chiral a,b-epoxy aldehyde intermediate, which is prepd. from L-lactate via Sharpless epoxidn. Stereoselective synthesis of maitotoxin GHI-ring system having a 1,2-diol side chain. [作者：Nagatomo, Masanori;Nakata, Tadashi;,期刊：Heterocycles, 页码：1069-1074 , 文章类型： 研究论文，,卷期：2008年76-2] The stereoselective synthesis of the maitotoxin GHI-ring system having a 1,2-diol side-chain was accomplished via successive SmI2-induced reductive cyclizations of b-alkoxyacrylate-aldehyde and optically active (E)-b-alk...