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55 巻, 5 号
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北原 武1997 年 55 巻 5 号 p. 356
発行日: 1997/05/01
公開日: 2009/11/16
ジャーナル フリーPDF形式でダウンロード (165K) -
青山 安宏1997 年 55 巻 5 号 p. 357-364
発行日: 1997/05/01
公開日: 2009/11/16
ジャーナル フリーMultiple interaction plays important roles in molecular recognition. In the present article are described recent advances in the supramolecular multiple interactions. It is composed of three parts. The first one deals with a strategic switch from convergent multiple interaction sites to divergent ones. The latter is suited not for host-guest complexation but for intermolecular network formation and hence allows molecular alignment control in crystals. In the second part is shown the use of templates to induce biologically-significant supramolecular structures such as α-helical folding of peptides and sugar clusters. The last part is concerned with how multiple hydrogen bonding interaction can become effective in aqueous media. Examples include a membrane-forming cooperation of hydrogen bonding and hydrophobic effect, a very strong adsorption of a macrocyclic sugar cluster on polar solid surfaces, and guest-binding supramolecular cavities in microporous crystals maintained by hydrogen-bonds.抄録全体を表示PDF形式でダウンロード (879K) -
鈴木 正昭, 古田 享史, 細谷 孝充1997 年 55 巻 5 号 p. 365-374
発行日: 1997/05/01
公開日: 2009/11/16
ジャーナル フリーAn opinion on the opportunity and the role of synthetic organic chemistry in 21st century's life science is described. Particularly emphasized is the importance of the creation of designed molecules. Designed molecules are the tools that can regulate biofunctions by stimulating or inhibiting target proteins such as membrane receptors through specific binding. The effective utilization of designed molecules will contribute to the elucidation of complex biosignal transduction mechanisms at the molecular level. The subject includes : (1) Introduction; (2) Definition of designed molecules; (3) Receptors and signal transduction (3.1) Membrane receptors and ion channels; (3.2) Protein kinases and H-inhibitors; (3.3) Immune response and receptor signaling; (3.4) Cell cycle and biosignals; (3.5) Lipids as signaling molecules; (3.6) From molecular level to vital systems; (4) Prostaglandins (PGs) and biofunctions (4.1) PG receptors and functions; (4.2) Design and synthesis of specific molecular probes for PG receptor signaling and the use in biology; (5) Perspectives in the 21st century. At present, the PG bioscience faces to a new phase based on molecular level investigation of the signaling functions of PG receptors. In this context, current topics in this field are overviewed in subject 4. The results described in subject 4.2. have been developed by authors in collaboration with biochemists.抄録全体を表示PDF形式でダウンロード (1613K) -
藁科 雅岐, 藤田 聡史, 宇都宮 隆志, 周 徳敏, 多比良 和誠1997 年 55 巻 5 号 p. 375-383
発行日: 1997/05/01
公開日: 2009/11/16
ジャーナル フリーIn the case of protein enzymes, the cleavage of phosphodiester bonds involves acid/base catalysis, with proton transfer occurring in the transition state. When the possibility of such a proton-transfer process was examined, it became apparent that no proton transfer occurs in the ribozyme reaction. This and other kinetic data are consistent with the proposal that ribozymes might exploit the general double-metal-ion mechanism of catalysis, with Mg2+ ions coordinating directly with the attacking and leaving oxygen moieties. As one of the coordination sites of Mg2+ ions, it is generally believed that a Mg2+ ion is directly coordinated with the pro-Rp oxygen of a scissile phosphate. However, our quantitation of the rescue capability of Mn2+ ions argued against the generally accepted mechanism of the electrophilic catalysis. Nevertheless, more recent time-resolved X-ray analysis supports the direct coordination of a Mg2+ ion with the pro-Rp oxygen, although the captured intermediate showed much lower cleavage activity than that measured in solution. It remains to be answered whether the captured intermediate really represents the transition state structure in solution.抄録全体を表示PDF形式でダウンロード (1257K) -
杉浦 幸雄, 永岡 真1997 年 55 巻 5 号 p. 384-392
発行日: 1997/05/01
公開日: 2009/11/16
ジャーナル フリーDNA recognition is a very important phenomenon in biology and chemistry, and the molecular basis of the sequence-specific DNA binding is the subject of investigations aimed at the rational design of molecules with specific biological activities. Minor-groove-binding polyamides containing N-methylimidazole and N-methylpyrrole amino acids achieve affinities and specificities comparable to DNA binding proteins. The synthetic oligosaccharide moiety of the antibiotic calicheamicin and the head-to -head dimer of this oligosaccharide bind to the minor groove of DNA in a sequence-selective manner preferring distinct target sequences. Zinc-finger libraries with different DNA-binding specificities based on a one-finger-three-nucleotide code have been developed successfully. On the other hand, DNA bending is also important regulators of biological process. Sequence-specific DNA bending ligands are designed to bind two noncontiguous sites in the major groove and induce a bent in the DNA. Molecules that specifically bind and bent any predetermined DNA sequence in the human genome would be useful tools in molecular biology and potentially in human medicine.抄録全体を表示PDF形式でダウンロード (1020K) -
梶本 哲也, 伊田 喜光1997 年 55 巻 5 号 p. 393-401
発行日: 1997/05/01
公開日: 2009/11/16
ジャーナル フリーCarbohydrates on cell surfaces play important roles in various cell adhesion processes such as bacterial and viral infection, neurtrophile recruitment, cell differentiation and so on by binding proteins like lectins, antibodies, and glycoenzymes (glycosidases and glycosyltransferases). Carbohydrate analogues which inhibit the interaction between carbohydrates and proteins are promising molecules to clarify and control biological functions of oligosaccharides, and some of the analoges were prepared by using aldolase catalyzed reactions without any tedious procedures. For example, a mimetic of sialyl Lewis X which is an ligand of E-selectin was synthesized by using L-threonine aldolase catalyzed reaction as a key step. In addition, synthetic approach to KDO and 4-azaiduronic acid by using kynureninase and the L-threonine aldolase, respectively, is almost achieved.
This review article shows solid phase synthesis and combinatorial synthesis of carbohydrates and treats the details about the utility of aldolases on making carbohydrate mimetics as one of the chemical approaches of glycotechnology.抄録全体を表示PDF形式でダウンロード (996K) -
宮川 博夫, 北村 一泰1997 年 55 巻 5 号 p. 402-409
発行日: 1997/05/01
公開日: 2009/11/16
ジャーナル フリーIt has been received that molecular dynamics simulation is a powerful tool to elucidate molecular behavior and physical property based on atomic level through many applications since Alder's first trial for the phase transition for a hard sphere system in 1957. Today, the use of this method is more increasing with the progress of computer hardware and of simulation software. Here, molecular dynamics simulation is reviewed in both technical and application aspects.抄録全体を表示PDF形式でダウンロード (1471K) -
西原 寛1997 年 55 巻 5 号 p. 410-416
発行日: 1997/05/01
公開日: 2010/01/28
ジャーナル フリーThe history of organic electronic conductors for half century is shortly reviewed and some recent topics on the synthesis of conducting polymers are presented. Organic conductors can be roughly divided into two categories, crystalline and polymeric materials, of which chemistry and physics have advanced markedly and a variety of examples have appeared. The crystalline materials involve superconducting low-dimensional charge-transfer salts and M3C60 (M is an alkali metal), and the polymeric conductors are mostly made of linearly π-conjugated organic polymers. One of the recent topics given is synthesis of poly (phenylene vinylene) that is one of the most fascinating materials of its high EL ability. Other topics described are synthesis of new class of conducting polymers, π-conjugated donor-acceptor copolymers and π-conjugated polymers involving transition metal complexes. The history clearly indicates that the role of synthetic chemists is still important for finding a breakthrough to open a new era of organic conducting materials.抄録全体を表示PDF形式でダウンロード (900K) -
岩村 秀, 井上 克也, 古賀 登1997 年 55 巻 5 号 p. 417-426
発行日: 1997/05/01
公開日: 2009/11/16
ジャーナル フリーDesign and construction of magnets based on free radicals are subjects of academic and technological importance in these decades. One of the most successful design strategies lies in using high-spin oligo- (aminoxyl) radical as bridging ligands for magnetic metal ions and assembling the former with the aid of the latter serving as templates. When the chains thus obtained in crystals are isotactic, the interchain interaction is limited. When they are syndiotactic, they develop into 2D networks and 3D crossed parallel structures. The ferromagnetically coupled 2p spins of the free radicals couple with 3d spins of the metal ions. While 1D complexes remain to be metamagnets with a magnetic transition temperature of 5.5-11 K, 2D and 3D complexes become ferri/ferromagnets with phase transition temperatures in the range 3.4-46 K. Whereas 1D complexes of Mn (hfac) 2 and Cu (hfac) 2 with diazodi (4-pyridyl) methane were dilute paramagnets, ferri- and ferromagnetic chains were established by photolysis, respectively, forming protoypes for the novel photomagnetic recording devices.抄録全体を表示PDF形式でダウンロード (1248K) -
丸山 厚, 赤池 敏宏1997 年 55 巻 5 号 p. 427-435
発行日: 1997/05/01
公開日: 2009/11/16
ジャーナル フリーInnovation in life science including medical science is essential to improve the quality of life in coming 21st century, in which human being must face serious problems due to the aging society, environmental issue, the food problem and so on. Highly functional and intelligent biomedical polymers is crucial for the innovation of medical cares. In this review, the authors make an effort to emphasize the importance of designing biomedical polymers which are capable of cooperating and harmonizing with living systems, because the living systems maintained their homeostasis by synchronizing complex and miscellaneous components. Biomedical materials which exhibit their functions in a cooperative and harmonizing manner with biomolecules, bio-assemblies and cells can open a new standard of gentle and truly affectionate medical cares. A lot of unique biomedical materials have been developed by designing and preparing new polymeric materials. A basic concept for designing of blood compatible materials, materials for cellular/tissue engineering and drug delivery systems will be focused.抄録全体を表示PDF形式でダウンロード (1543K) -
雨宮 成, 梅澤 喜夫1997 年 55 巻 5 号 p. 436-443
発行日: 1997/05/01
公開日: 2009/11/16
ジャーナル フリーThe signal transduction/amplification based on the change of membrane potential or permeability can be modulated by molecular recognition of analytes with artificial receptors at the membrane surfaces, making it a very interesting approach to chemical sensing. Membrane potential was changed with the following modes of molecular recognition at the liquid membrane surfaces. (i) Multitopic hydrogen bonding of nucleobases or inorganic anions by receptors with cytosine residue or with two urea (thiourea) groups, respectively. (ii) Inclusion of nonpolar moieties of amine analytes by a calix [6] arene hexaester or a β-cyclodextrin derivative. The principles of ion-channel sensors based on chemically switchable membrane permeability changes are demonstrated by intermolecular as well as intramolecular channels using monolayers formed with hydrogen bonding receptors and the β-cyclodextrin derivative. Finally, examples of fluorescence mediated sensing of guanosine derivatives based on multitopic hydrogen bonding and orthophosphate ion sensors based on a quartz crystal microbalance are also presented.抄録全体を表示PDF形式でダウンロード (1163K) -
村上 正浩, 伊藤 嘉彦1997 年 55 巻 5 号 p. 444-451
発行日: 1997/05/01
公開日: 2009/11/16
ジャーナル フリーBreaking of inert chemical bonds by transition metals under homogeneous conditions has recently made rapid progress. In this review is described an overview of this field, especially the feature related to organic synthesis. The first part deals with breaking of carbon-hydrogen bonds. Ruthenium complexes catalyze the direct addition of ortho carbon-hydrogen bonds in aromatic ketones to olefins with high efficiencies and selectivities. A variety of analogous synthetic reactions involving breaking of Csp2-H bonds have been developed. The latter part features a recent aspect on the activation of C-C bonds through a process of oxidative addition to a soluble transition metal complex. Selective breaking of the C-C bonds α to the carbonyl group of cyclobutanones is achieved by a rhodium (I) complex.抄録全体を表示PDF形式でダウンロード (920K) -
平竹 潤, 小田 順一1997 年 55 巻 5 号 p. 452-459
発行日: 1997/05/01
公開日: 2009/11/16
ジャーナル フリーOne of the major goals of catalytic antibodies is to provide tailor-made catalysts for use in practical organic synthesis. Reflecting the increasing demand for enantio- and regioselective catalysts in organic synthesis, the scope of antibody catalysis now encompasses a broad array of synthetically important reactions such as highly enantio- and regioselective C-C bond formations and programmable control of disfavored reaction pathways. The advances in antibody catalysis have now reached the stage where it is actually applied to preparative scale synthesis of optically active compounds. In this review, we focus on how antibody catalysis is designed and adopted to organic synthesis and describe (1) the antibody-catalyzed Diels-Alder reactions and aldol condensations as examples of highly enantio- and regioselective C-C bond formations, (2) the control of reaction pathways and selectivities by antibodies, (3) the catalytic antibodies with broad substrate specificity, (4) the applications of antibody catalysis to preparative organic synthesis, and (5) the antibody catalysis in organic solvents and the antibody immobilization.抄録全体を表示PDF形式でダウンロード (1138K) -
大谷 文章1997 年 55 巻 5 号 p. 460-465
発行日: 1997/05/01
公開日: 2009/11/16
ジャーナル フリーPrinciple and recent development of photochemical reactions which are applicable to organic syntheses are interpreted. Special emphasis is placed on the new types of heterogeneous photoinduced reactions, e.g., semiconductor photocatalytic reactions, photoreactions of solid, and those of incorporated or intercalation compounds. Some industrialized photoreactions, e.g. photonitrosation of cyclohexane, or photochlorination of pyridines are also reviewed in order to see the perspective for application of photoreactions.抄録全体を表示PDF形式でダウンロード (867K) -
過去, 現在, 未来菅原 徹, David G. CORK1997 年 55 巻 5 号 p. 466-473
発行日: 1997/05/01
公開日: 2009/11/16
ジャーナル フリーOrganic synthetic chemistry utilises scientific technology from various fields but compared to the great advances seen in the automation of analytical instruments over the last 20 years, the synthesis of organic compounds has been relatively slow to move from a largely manual process. Automation of synthesis is not only important for increasing efficiency, precision and safety but also decreasing labor and exploring new synthetic methodologies. In this review of automated synthesis apparatus we broadly divide them into two categories;those using robotic transfer of a reagent, reactant, product or vessel, and others that only use flow-lines for transfers between fixed reactors. These categories are then sub-divided into systems and workstations according to the extent of the operations and functions. We highlight some of the representative past and present automated synthesis apparatus and look at what the future may hold in the way of miniaturized and high-throughput automated synthesis.抄録全体を表示PDF形式でダウンロード (1661K) -
深瀬 浩一1997 年 55 巻 5 号 p. 474-479
発行日: 1997/05/01
公開日: 2009/11/16
ジャーナル フリーA review on recent advances of combinatorial chemistry is described. Following topics are discussed : 1) molecular diversity, 2) split synthesis vs. parallel synthesis, mixture vs. discrete, 3) solid phase synthesis vs. solution synthesis, 4) universal library vs. focused library.抄録全体を表示PDF形式でダウンロード (827K) -
古賀 伸明1997 年 55 巻 5 号 p. 480-486
発行日: 1997/05/01
公開日: 2009/11/16
ジャーナル フリーRecent progress in theoretical methods for the calculations of organic reactions, specially density functional theory (DFT) and integrated MO+MM (IMOMM) method, will be reviewed. DFT calculations have been performed in literature more frequently than before, in order to study organic reactions, because the DFT methods recently proposed, the hybrid methods such as B3LYP, have given accurate results comparable to expensive ab initio methods. In the IMOMM calculations, an active part of the system is handled by the MO method, the remainder is treated by the molecular mechanics force field, and the geometry is optimized fully using the sum of MO and MM energies. Thus, a large molecular system with bulky substituents could be studied theoretically. Its application to the oxidative addition of H2 to Pt (PR3) 2 will be discussed.抄録全体を表示PDF形式でダウンロード (893K) -
杉浦 幸雄, 岩村 秀, 梅澤 喜夫, 村上 正浩1997 年 55 巻 5 号 p. 487
発行日: 1997/05/01
公開日: 2009/11/16
ジャーナル フリーPDF形式でダウンロード (167K)
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