巻号一覧
57 巻, 12 号
選択された号の論文の9件中1～9を表示しています
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辻 二郎1999 年 57 巻 12 号 p. 1036-1050
発行日: 1999/12/01
公開日: 2009/11/16
ジャーナル フリーThe reaction of π-allylpalladium chloride with malonate to give allylmalonate discovered in 1965 marked the birth of π-allylpalladium chemistry. A group of new synthetic reactions, developed subsequently in our laboratory based on Pd-catalyzed decarboxylation of allyl carbonates, allyl β-keto carboxylates, and allyl formates are summarized. All these reactions proceed under neutral conditions. Allyl carbonates are very active for allylation of nucleophiles without a base. A new generation of β- keto esters and malonates was developed by the introduction of the Pd-catalyzed reaction of their allylic esters. Hydrogenolysis of allylic compounds with triethylammonium formate proceeds regio- and stereoselectively to afford regio- and stereodefined olefins. The hydrogenolysis also can be used for deprotection of the allyl protecting group.抄録全体を表示PDF形式でダウンロード (1498K) -
内山 真伸, 根東 義則, 坂本 尚夫1999 年 57 巻 12 号 p. 1051-1063
発行日: 1999/12/01
公開日: 2009/11/16
ジャーナル フリーAs a new type of zincate, we designed “highly coordinated” zincates, Me3Zn (R) Li2 (R = Me, CN, SCN). On the basis of their excellent chemical yields and chemoselectivities, these species were considered to be differentiated from ordinary triorganozincates, R3ZnLi. We discuss the structure of the newly designed zincates using spectroscopic studies. All results strongly support the fact that these newly designed zincates are new category of zincate species.
We also designed various dialkylzinc hydride “ate” complexes and investigated the reactivities of these zincates toward benzophenone. The results clearly reveal that dimethylzinc hydrides are the most powerful and selective zincate for the reduction of the carbonyl group.抄録全体を表示PDF形式でダウンロード (1559K) -
浅野 泰久1999 年 57 巻 12 号 p. 1064-1072
発行日: 1999/12/01
公開日: 2009/11/16
ジャーナル フリーWe screened microorganisms for various new enzymes, which were used in the synthesis of organic chemicals. A new hydro-lyase from Arthrobacter sp. catalyzed the synthesis of 87 grams/liter of D-malate from maleic acid in 72% yield. A. denitrificans produced 27 g of (S) - (+) -citramalate of 99.9 % ee in 69% yield. Phenylalanine dehydrogenase (PheDH) is used in the colorimetric micro-determination of L-Phe to detect phenylketonuria (PKU) in the blood of neonates in Japan. The structure of a new enzyme opine dehydrogenase (ODH) from Arthrobacter sp., has been solved to 1.8 Å resolution. Optically pure secondary amine carboxylic acids were synthesized by ODH. Picolinic acid derivatives were synthesized by Pseudomonas catechol 2, 3-oxygenase. Nearly 20 grams/liter of theobromine was produced from caffeine in a yield of 92% by P. putida cells. A new enzyme alkaline D-peptidase from B. cereus was used for oligomerization of D-Phe methylester.抄録全体を表示PDF形式でダウンロード (1346K) -
豊岡 尚樹, 百瀬 雄章, 根本 英雄1999 年 57 巻 12 号 p. 1073-1083
発行日: 1999/12/01
公開日: 2009/11/16
ジャーナル フリーThis article describes a design and synthesis of new 3-piperidinol type of chiral building blocks and its application to the biologically active alkaloids synthesis. Both enantiomers of these chiral building blocks were prepared by using a biocatalysis in enantiomerically pure state. As an application of the above chiral building blocks to alkaloid synthesis, we demonstrated the diastereodivergent synthesis of the 3-piperidinol alkaloids cassine, spectaline, prosafrinine, iso-6-cassine, prosophylline, prosopinine, and also established the flexible route to the 5, 8-disubstituted indolizidine or 1, 4-disubstituted quinolizidine type of Dendrobates alkaloids. As another application to the synthesis of biologically active alkaloids, we accomplished the first enantioselective total synthesis of the marine alkaloids clavepictines A, B, and pictamine by using the highly stereoselective Michael type of quinolizidine ring closure reaction as the crucial step, respectively.抄録全体を表示PDF形式でダウンロード (1083K) -
木村 太郎, 新海 征冶1999 年 57 巻 12 号 p. 1084-1091
発行日: 1999/12/01
公開日: 2009/11/16
ジャーナル フリーIn biological systems saccharides play important roles as signals, triggers and name tags. Saccharide structure can include a large amount of information using the specific configuration of hydroxyl groups. It has been known that phenylboronic acid can act as an artificial receptor for saccharides, because boronic acid forms complexes with saccharides rapidly and reversibly in aqueous media. When the complex is formed, the neutral sp2-hybridized boron atom changes to the anionic sp3-hybridized boron atom. We synthesized many amphiphiles and polypeptides bearing phenylboronic acids. They formed specific higher-order structures in aqueous media, which changed in response to added saccharides. For example, the phenylboronic-acid-appended-amphiphiles formed stable membranes and gels in the presence of saccharides. In addition, saccharides induced chiral orientation of the amphiphile assemblies. Although phenylboronic-acid-appended-polylysine formed a random coil structure in neutral water, added saccharides induced the coil-to-helix transition.抄録全体を表示PDF形式でダウンロード (1120K) -
山口 健太郎1999 年 57 巻 12 号 p. 1092-1107
発行日: 1999/12/01
公開日: 2009/11/16
ジャーナル フリーThe interpretation of the significance of the results from X-ray crystallographic analysis in organic chemistry is discussed. It is important to investigate the three-dimensional precise structure for the research on characterization and chemical reactivity. Therefore, structure establishment for the basic molecular units such as azabenzenes is introduced to present its achievement in chemistry involving heterocyclic aromatic compounds, in the first place. In addition, stereochemistry of aromatic amide compounds and investigations on asymmetric transformation are the subjects with respect to X-ray analysis. Secondly, the structures of natural organic compounds, biologically active substances, nucleic acid compounds, and mutagenic or carcinogenic principles are discussed. Finally, an achievement of X-ray analysis in characterization of nano-scale supramolecular compounds is presented.
The latest achievements based on my personal experience over 20 years in X-ray analyses are described to confirm its significance in organic chemistry. It is also tried to present the progress now being made in X-ray analysis in prospective.抄録全体を表示PDF形式でダウンロード (2366K) -
西 孝夫, 木村 征夫1999 年 57 巻 12 号 p. 1108-1115
発行日: 1999/12/01
公開日: 2009/11/16
ジャーナル フリーPDF形式でダウンロード (1236K) -
吉田 康夫1999 年 57 巻 12 号 p. 1116-1117
発行日: 1999/12/01
公開日: 2009/11/16
ジャーナル フリーPDF形式でダウンロード (187K) -
辻 二郎, 豊岡 尚樹, 木村 太郎, 山口 健太郎1999 年 57 巻 12 号 p. 1118
発行日: 1999/12/01
公開日: 2009/11/16
ジャーナル フリーPDF形式でダウンロード (155K)
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