巻号一覧
64 巻, 8 号
選択された号の論文の10件中1～10を表示しています
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塚野 千尋, 佐々木 誠2006 年 64 巻 8 号 p. 808-818
発行日: 2006/08/01
公開日: 2010/10/20
ジャーナル フリーGymnocin-A is a polycyclic ether toxin, isolated from the notorious red tide dinoflagellate, Karenia mikimotoi. Structurally, it is characterized by 14 contiguous and saturated ether rings and a 2-methyl-2-butenal side chain. The toxin is a rare polycyclic ether natural product that exhibits cytotoxicity against P 388 murine leukemia (IC50=1.3 μg/mL); however, the biological mechanism of action remains unknown to date. We have accomplished a highly convergent and efficient total synthesis of gymnocin-A by using our developed B-alkyl Suzuki-Miyaura coupling-based methodology. The convergent nature of our synthesis is well suited for preparation of various structural analogues of gymnocin-A to explore the structure-activity relationship (SAR). The results of SAR studies indicated that an α, β-unsaturated aldehyde functionality of the side chain and the molecular length of the polycyclic ether skeleton were the crucial structural elements required for cytotoxicity.抄録全体を表示PDF形式でダウンロード (1529K) -
滝川 浩郷2006 年 64 巻 8 号 p. 819-826
発行日: 2006/08/01
公開日: 2010/10/20
ジャーナル フリーAllelopathy is commonly defined as any direct or indirect effect by one plant, including microorganisms, on another through the production of chemical compounds released into the environment. Recently, allelopathic agents have received considerable attention due to the agricultural potential as environmentally benign agrochemicals from the viewpoint of environmental conservation. Thus, we have been engaged in synthetic studies on allelopathic agents and consequently have accomplished the syntheses of two allelopathic terpenoids, annuionone A and brevione B. In this account, we would like to present these two synthetic studies.抄録全体を表示PDF形式でダウンロード (1287K) -
新田 百合子2006 年 64 巻 8 号 p. 827-835
発行日: 2006/08/01
公開日: 2010/10/20
ジャーナル フリーThe studies on the enantioselective hydrogenation of prochiral olefins with heterogeneous palladium catalysts in these 20 years are briefly reviewed. The experimental results mainly on the hydrogenation of α, β-unsaturated carboxylic acids with cinchona alkaloids-modified Pd catalysts are described from the points of substrate structure, modifier structure, catalyst preparation method, support texture, pretreatments, reaction conditions (e.g., solvent, hydrogen pressure, reaction temperature, additives, etc.), and the reaction mechanism. The highest ee up to81% has been achieved for the reaction of (E) -2, 3-diphenylpropenoic acid, and up to92% for its derivative, (E) -2, 3-di (4-methoxyphenyl) propenoic acid, with a cinchonidine-modified Pd/C catalyst under an optimized reaction condition. More systematic studies for understanding the reaction mechanisms will lead to further improvement of this catalytic system.抄録全体を表示PDF形式でダウンロード (1484K) -
和田 健司, 光藤 武明2006 年 64 巻 8 号 p. 836-844
発行日: 2006/08/01
公開日: 2010/10/20
ジャーナル フリーPreparation of novel oligosilsesquioxanes-based materials and metal-containing ones as homogeneous and heterogeneous catalysts of excellent activity are reviewed. The authors examined the activity of a V-containing silsesquioxane as a homogeneous catalyst for the photo-oxidation of simple alkanes. For the epoxidation of alkenes catalyzed by Ti-silsesquioxanes, the presence of alkenylsilyl substituents around the Ti center shows significant promotional effects. By utilizing silsesquioxanes bearing appropriate functional groups, novel caged molecules with organic-inorganic hybrid structures were prepared as well as soluble cooligomers, starburst-type polymers, and a dendrimer containing metallasilsesquioxanes. Furthermore, the authors found that these metal-containing silsesquioxanes can be good precursors of oxide catalysts with high BET surface areas and uniformly-controlled pores. Remarkably, the catalysts containing V and Al species were found to show excellent activity for photo-assisted aerobic oxidation of methane into methanal and the cracking of cumene, respectively.抄録全体を表示PDF形式でダウンロード (1510K) -
三好 徳和, 池原 大哲, 松尾 強, 幸野 正志, 松井 亜希, 和田 眞2006 年 64 巻 8 号 p. 845-852
発行日: 2006/08/01
公開日: 2010/10/20
ジャーナル フリーOrganometallic compounds comprise some of the most versatile reagents in organic synthesis, and among them are organometallic compounds of alkaline-earth elements. Numerous reports have been published on the Grignard (or Barbier) reaction using metallic magnesium and alkyl halides. Furthermore, there are various reports on the preparation and reactivity of the organometallic compounds of calcium and barium. In contrast, fewer studies on the preparation and reactivity of organostrontium compounds were found in the literature. As the results on our investigation, it's found that in the presence of metallic strontium, the Barbier-type alkylation of aldehydes with alkyl iodides proceeded smoothly at-15°C under an argon atmosphere to afford the corresponding alkylated alcohols in moderate to good yields. The Barbier-type alkylation of imines with alkyl iodides also took place smoothly at room temperature under an argon atmosphere to give the corresponding alkylated amines in good yields. Aromatic aldimines reacted with metallic strontium in the presence of a catalytic amount of iodine to obtain the self-coupling products in good yields. Furthermore, the Barbier-type alkylation of esters with alkyl iodides proceeded smoothly at room temperature under an argon atmosphere to afford the corresponding dialkylated alcohols in good yields.抄録全体を表示PDF形式でダウンロード (1423K) -
関 雅彦2006 年 64 巻 8 号 p. 853-866
発行日: 2006/08/01
公開日: 2010/10/20
ジャーナル フリーPractical approaches to multifunctional compounds through palladium on activated carbon, (Pd/C) -catalyzed Heck, Suzuki and Miyaura, Sonogashira, Fukuyama coupling and others are discussed. Correlation of the properties of the heterogeneous catalysts, e.g., palladium distribution and reduction degree, with the efficiency of the reaction has been observed and largely depends upon the type of the reactions. A critical role of the solid support is supposed to help palladium highly disperse on the solid surface to form active Pd complex without aggregating to inactive palladium black. The reactions are so practical as to be applied to cost-effective large-scale production of multifunctional intermediates for drug-synthesis.抄録全体を表示PDF形式でダウンロード (2168K) -
今村 圭佑2006 年 64 巻 8 号 p. 867-868
発行日: 2006/08/01
公開日: 2010/10/20
ジャーナル フリーNitrogen-containing compounds have unique reactivities and a variety of bioactivities. Herein, were described several organic synthetic approaches to multi-nitrogen-containing iminoquinone skeletons, and their applications to natural product synthesis.抄録全体を表示PDF形式でダウンロード (330K) -
松本 和弘2006 年 64 巻 8 号 p. 869-870
発行日: 2006/08/01
公開日: 2010/10/20
ジャーナル フリーOptically active epoxides are versatile synthetic intermediates and asymmetric epoxidation is the most powerful method for their synthesis. Aqueous hydrogen peroxide is clean and atom-efficient and the epoxidation with it has been extensively studied. Thus, rapid advancement of asymmetric epoxidation using hydrogen peroxide has been made in recent years. In this Review de Debut, representative works of asymmetric epoxidation with aqueous hydrogen peroxide including a recent progress are overviewed.抄録全体を表示PDF形式でダウンロード (364K) -
永田 浩一, 出島 栄治2006 年 64 巻 8 号 p. 871-873
発行日: 2006/08/01
公開日: 2010/10/20
ジャーナル フリーPDF形式でダウンロード (432K) -
塚野 千尋, 佐々木 誠, 滝川 浩郷, 和田 健司2006 年 64 巻 8 号 p. 874
発行日: 2006/08/01
公開日: 2010/10/20
ジャーナル フリーPDF形式でダウンロード (172K)
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