巻号一覧
60 巻, 7 号
選択された号の論文の8件中1～8を表示しています
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広井 邦雄2002 年 60 巻 7 号 p. 646-656
発行日: 2002/07/01
公開日: 2010/01/22
ジャーナル フリーOur recent results of catalytic asymmetric synthesis with chiral organosulfur ligands are reviewed. We have developed new chiral ligands with various coordinatable functionalities such as chiral sulfinyl, sulfenyl, phosphinyl, phosphinoamino, 1, 3-oxazoline, and imino groups, and applied them to Lewis acid- or transition metal-catalyzed asymmetric alkylations and cycloaddition reactions. The usefulness as chiral ligands in catalytic asymmetric alkylations and Diels-Alder reactions were demonstrated. The use of 2-phosphinophenyl and 2- (phosphi-noamino) phenyl 2-methoxy-1-naphthyl sulfoxide in palladium-catalyzed asymmetric alkylations provided high enantioselectivity (82 and 97%, respectively). 4- (1-Methoxyisopropyl) -2- [2- (2-methoxy- 1-naphthalenesulfinyl) phenyl] -1, 3-oxazoline was applied to MgI2-catalyzed Diels-Alder reactions as a chiral ligand, achieving high enantioselectivity (92%). Some of the structure of the intermediary metal complexes coordinated by the chiral ligands were determined by the X-ray crystallographic analysis. The mechanisms of the asymmetric synthesis with the ligands are proposed on the basis of the structure of the intermediary complexes and the stereo-chemical results obtained.抄録全体を表示PDF形式でダウンロード (1641K) -
西 剛秀2002 年 60 巻 7 号 p. 657-667
発行日: 2002/07/01
公開日: 2010/01/22
ジャーナル フリーTachykinin actions are mediated by at least three distinct receptors designated as NK1, NK2 and NK3. The endogeneous tachykinin ligands interact with all tachykinin receptors, although there is a defined agonist rank order of potency such that substance P (SP), neurokinin A (NKA), and neu-rokinin B (NKB) have the highest affinities for the NK1, NK2 and NK3 receptors, respectively. SP, NKA, and NKB have all been linked to numerous chronic diseases, including asthma and chronic obstructive pulmonary disease. Speculating that a combined tachykinin receptor antagonist may be of greater benefit than a selective antagonist in the treatment of pulmonary diseases, we designed a series of novel morpholine and oxazolidine analogues (I and II). We report herein the synthesis and structure-activity relationships of novel morpholine- and oxazolidine-based ana-logues with regards to NK1, NK2 and NK3 tachykinin receptor binding affinity. Efficient and practi-cal synthetic methods for the preparation of enantiomerically pure 2- [(2R) -arylmorpholin-2-yl] ethanols 8a-d and 2- [(5R) -aryloxazolidin-5-yl] ethanols 23a-d, key intermediates of I and II are described. Among these analogues, the compounds that possess properties such as spiro [benzo [c] thiophene-1 (3H), 4'-piperidine] - (2S) -oxide (S) -29 and spiro [((2S) -hydroxy) indane-1, 4'-piperidine] (S) -41 moiety had strong binding affinities to the tachykinin receptor. This report also describes efficient and practical synthetic methods for the preparation of enan-tiomerically pure (S) -29 and (S) -41. One of the enantiomers, (S, R) -42 HCl salt (R-113281), exhib-ited high binding affinities for NK1, NK2 and NK3 receptors in humans and guinea pigs. In vivo, R-113281 exerted highly potent antagonism toward SP-induced tracheal vascular hyperpermeabili-ty and NKA-, NKB- and capsaicin-induced bronchoconstriction in guinea pigs.抄録全体を表示PDF形式でダウンロード (1450K) -
〓合 憲三, 佐藤 格, 柴田 高範2002 年 60 巻 7 号 p. 668-678
発行日: 2002/07/01
公開日: 2010/01/22
ジャーナル フリーAsymmetric automultiplication of chiral compounds by asymmetric autocatalysis is realized for the first time where a chiral product acts as a chiral catalyst for its own production. Practically perfect asymmetric autocatalysis (>99%, >99.5% ee) is attained using pyrimidyl alkanol as an asymmetric autocatalyst in the enantioselective addition of diisopropylzinc to pyrimidine-5-carbalde-hyde. Moreover, asymmetric autocatalyst with very low ee enhances its ee significantly up to >99.5% ee during the automultiplication without the assistance of any other chiral auxiliaries. Amino acids and [6] helicene with very low ee which are produced by asymmtric photolysis and photosynthesis using circularly polarized light (CPL) serve as chiral initiators of asymmetric auto-catalysis, and pyrimidyl alkanol with high ee is obtained. Inorganic chiral crystals such as quartz and sodium chlorate also work as chiral initiators. These results correlate for the first time the proposed origins of chirality of organic compounds such as CPL and quartz with the chirality of organic compounds with very high ee.抄録全体を表示PDF形式でダウンロード (1684K) -
鈴木 芳和, 村田 毅, 高尾 賢一, 只野 金一2002 年 60 巻 7 号 p. 679-690
発行日: 2002/07/01
公開日: 2009/11/13
ジャーナル フリーThe Diels-Alder reaction is one of the most valuable reactions in synthetic organic chemistry. This [4+2] cycloaddition produces a cyclohexene derivative with concomitant generation of up to four new stereogenic centers. Particularly, intramolecular version has attracted many organic chemists due to forming polycyclic skeleton with high regio- and stereoselectivity under mild conditions. Thus, the intramolecular Diels-Alder reaction has shown its broad utility for the construc-tion of various complex ring systems. In this review, we summarize the regio-, endo/exo, and/or π-facial selective intramolecular Diels-Alder reactions of type I for total synthesis of natural prod-ucts, which have been published in recent years.抄録全体を表示PDF形式でダウンロード (1644K) -
岩尾 正倫, 福田 勉2002 年 60 巻 7 号 p. 691-700
発行日: 2002/07/01
公開日: 2009/11/13
ジャーナル フリーThis article reviews the regioselective lithiations of indole derivatives. The C-2 lithiation can be readily achieved by utilizing directed lithiation promoted by a protecting (directing) group on indole nitrogen. The C-3 lithiation has been carried out mainly by halogen-lithium exchange of N-protected 3-bromo (or iodo) indoles. The lithiation at the benzenoid portion of indole has been performed by several unique methods, which are designed by considering the specific properties of indole ring and N-protecting groups. These regioselective lithiations have been nicely applied for the short-step synthesis of a number of indole-containing natural products.抄録全体を表示PDF形式でダウンロード (1576K) -
菅野 憲一, 藤井 政幸2002 年 60 巻 7 号 p. 701-707
発行日: 2002/07/01
公開日: 2010/01/22
ジャーナル フリーThis review summarized recent progress in synthetic chemistry in microchannel reactor, in which the feature of microchannel reactor itself and variety of reactions in microchannel reactor were presented. There is a basic difference between fluidic system in batch scale and that in microchannel which is caused by difference of those geometry. First, solution forms laminar flow in microchannel. Second, short diameter of microchannel enhances the efficiency of transport of mass and heat. Recent reports revealed that microchannel reactor is not only feasible tool for a safe and highly efficient reaction, also feasible tool for highly stereo-controlled or rapid reactions.抄録全体を表示PDF形式でダウンロード (1324K) -
太原 研二2002 年 60 巻 7 号 p. 708-710
発行日: 2002/07/01
公開日: 2009/11/13
ジャーナル フリーPDF形式でダウンロード (366K) -
広井 邦雄, 西 剛秀, 〓合 憲三, 佐藤 格, 菅野 憲一2002 年 60 巻 7 号 p. 711
発行日: 2002/07/01
公開日: 2009/11/13
ジャーナル フリーPDF形式でダウンロード (207K)
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