巻号一覧
60 巻, 6 号
選択された号の論文の7件中1～7を表示しています
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諸橋 直弥, 壹岐 伸彦, 宮野 壮太郎2002 年 60 巻 6 号 p. 550-562
発行日: 2002/06/01
公開日: 2009/11/13
ジャーナル フリーThiacalixarenes are new members in the calixarene family, which are readily accessible by reacting p-alkylphenols with elemental sulfur using NaOH as a base catalyst. With the progress of work, it has been demonstrated that these sulfur-bridged macrocycles are not the simple substitute for parent calixarenes but have their own inherent properties due to sulfur functionality. This review discloses the syntheses and modifications of thiacalixarenes and development of their intrinsic functions that cannot be attained by the conventional methylene-bridged counterparts.抄録全体を表示PDF形式でダウンロード (2215K) -
入江 一浩, 大東 肇2002 年 60 巻 6 号 p. 563-572
発行日: 2002/06/01
公開日: 2010/01/22
ジャーナル フリーProtein kinase C (PKC) isozymes play a critical role in many signal transduction pathways and are also main targets of tumor-promoting phorbol esters. Conventional and novel PKC isozymes contain two cysteine-rich C 1 domains (C 1 A and C 1 B), both of which are candidates for phorbol ester binding sites. These C 1 domains of about 50-70 amino acids were synthesized by an Fmocsolid phase strategy, and were successfully folded by zinc treatment. We measured the dissociation constants (Kd's) of [3H] phorbol-12, 13-dibutyrate for all PKC C 1 peptides. Most of the C 1 peptides showed strong PDBu binding affinities with Kd's in the nanomolar range (0.45-7.4 nM) comparable to the respective whole PKC isozymes. The resultant C 1 peptide library can be used to screen for new ligands with PKC isozyme and importantly C 1 domain selectivity. We have recently developed a new lactone analogue of benzolactams (6) which shows significant selectivity in the PKCη-C 1 B binding on the basis of the structure-activity relationship of teleocidin-type tumor promoters.抄録全体を表示PDF形式でダウンロード (1842K) -
林 高史2002 年 60 巻 6 号 p. 573-580
発行日: 2002/06/01
公開日: 2009/11/13
ジャーナル フリーMyoglobin, one of the hemoproteins, is a well-known protein which has a protoporphyrin IX iron complex via noncovalent interaction. Therefore, a myoglobin with a synthetic heme is readily available by reconstitutional method. We have recently prepared various heme moieties having modified heme-propionates and incorporated them into an apomyoglobin to obtain a reconstituted protein. The myoglobin has an artificially created interface which acts as the binding domain to form a protein-protein or protein-small substrate complex. As a result, the myoglobin is converted to an electron transfer protein or oxidase. Thus, the present method gives a unique function to the myoglobin surface. Furthermore, it is found that the modification of heme framework is also an attractive approach to improving physiological function of hemoproteins. For example, an iron porphycene as a structural isomer of the heme is a good prosthetic group for the myoglobin to show a high dioxygen affinity. The net results propose that the reconstitutional method of hemo-proteins will serve as a new way in creating a functionalized protein by organic synthetic method.抄録全体を表示PDF形式でダウンロード (1575K) -
宇野 英満, 小野 昇2002 年 60 巻 6 号 p. 581-592
発行日: 2002/06/01
公開日: 2010/01/22
ジャーナル フリーBicyclo-, benzobicyclo-, and naphthobicyclo- [2.2.2] octadiene-fused porphyrins were prepared from ethano-bridged isoindole derivatives via the common methods such as cyclic tetramerization, MacDonald [2+2], and [3+1] porphyrin syntheses. Heating these porphyrins over 200°C caused the retro Diels-Alder reaction leading to quantitative extrusion of ethylene to give the corresponding benzo-, naphtho-, and anthra-fused porphyrins, UV absorption of which showed efficient red-shift compared to those of the starting porphyrins. Upon the thermal treatment, the very bulky bicyclic-ring-fused porphyrins readily soluble in common solvents were converted to the flat, insoluble, conjugation-expanded porphyrins, purification of which often encountered difficulty. This methodology provides not only an easy access to highly conjugated porphyrins and related chromophores in very high quality, but also a significant conversion of soluble dyestuffs to insoluble pigments.抄録全体を表示PDF形式でダウンロード (1815K) -
大須賀 秀次, 田中 和彦2002 年 60 巻 6 号 p. 593-603
発行日: 2002/06/01
公開日: 2009/11/13
ジャーナル フリーHelicenes are a class of ortho-condensed polycyclic helical aromatic compounds, which have high optical rotational values and optical stability. In this report, we wish to describe the synthesis of optically active heterohelicenes and their characteristic structures. Three approaches to the synthesis of optically active helicenes were studied : (1) diastereoselective photocyclization of 1, 2-diarylethylenes, (2) kinetic resolution of racemic helicenediols 9 by lipase-catalyzed enantios-elective transesterification, and (3) diastereoselective biaryl coupling and stereospecific transformation of axial chirality to helicity. The racemic and optically active helicenediols 9 crystallize with ethanol, 1, 2-dichloroethane and testosterone to form clathrates. Single crystal X-ray analyses of the clathrates show that 9 has flexibilty and the dihedral angles between terminal thiophene rings vary from 38.0° to 54.5°, indicating that helicenediol 9 acts as a “molecular spring”. The bridged heterohelicenes 20 and 21 were also synthesized in order to determine the relationship between helical structures and spectral properties.抄録全体を表示PDF形式でダウンロード (1728K) -
望月 隆, 渡辺 由紀子, 蔵方 慎一, 汐崎 正生2002 年 60 巻 6 号 p. 604-614
発行日: 2002/06/01
公開日: 2009/11/13
ジャーナル フリーLPS-antagonists are promising candidates for anti-septicemia drugs. The lipid A molecule, the core component of LPS for its endotoxic activity, was used as a lead compound to search for stable compounds having LPS-antagonistic activity. From our investigation of lipid A-type pyrancarboxylic acid derivatives, the following were revealed : 1) the 1-α-phosphate group of the lipid A molecule was exchangeable to an α-oriented carboxy group without loss of activity; 2) the number of fatty acid chains in the molecule is critical for whether it shows LPS-agonistic or -antagonistic activity; and 3) conversion of the ester bonds to ether bonds in lipid A-type LPS-antagonists did not affect their LPS-antagonistic activity. We also found several LPS-antagonistic pyrancarboxylic acid derivatives composed of monosaccharides.抄録全体を表示PDF形式でダウンロード (1891K) -
宮野 壮太郎, 入江 一浩, 林 高史, 望月 隆2002 年 60 巻 6 号 p. 615
発行日: 2002/06/01
公開日: 2009/11/13
ジャーナル フリーPDF形式でダウンロード (231K)
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