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Volume 65, Issue 9
Displaying 1-9 of 9 articles from this issue
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Takamitsu Hosoya2007 Volume 65 Issue 9 Pages 842-851
Published: September 01, 2007
Released on J-STAGE: October 20, 2010
JOURNAL FREE ACCESSWe have designed and synthesized an azido-functionalized photoaffinity probe, [125I] GIF-0082, based on the structural modification of dantrolene. This compound specifically suppresses physiological Ca2+ release from sarcoplasmic reticulum (SR) of skeletal muscle without affecting Ca2+-induced Ca2+ release (CICR). Learning from the experience of handling the radioisotope (RI) labeled probe, we have developed a novel method of RI-free photoaffinity labeling in order to realize direct analysis of photolabeled proteins. This method utilizes a compact bifunctional probe consist of a photoreactive group and an aliphatic azido group that survives photolysis. By using this probe, a target protein is photo-cross-linked (Step 1), and then a detectable group is introduced by Staudinger-Bertozzi ligation using an alkyl azido moiety (Step 2). The utility of the method has been demonstrated by specific labeling of the catalytic portion of human HMG-CoA reductase using a diazido-functionalized cerivastatin derivative, photovastatin CAA 1, and a triarylphosphine derivative, GIF-0373, equipped with a fluorescein structure. The protocol has been also applied to the photolabeling of target proteins for a diazido-functionalized dantrolene derivative, GIF-0430.View full abstractDownload PDF (1956K) -
Takanori Fukushima, Wusong Jin, Takuzo Aida2007 Volume 65 Issue 9 Pages 852-861
Published: September 01, 2007
Released on J-STAGE: October 20, 2010
JOURNAL FREE ACCESSThis review article describes graphitic nanotubular objects formed by programmed self-assembly of Gemini-shaped hexa-peri-hexabenzocoronene (HBC) derivatives. The nanotubes are characterized by an aspect ratio greater than 1000 and have a uniform diameter of 20 nm, which is an order of magnitude larger than those of carbon nanotubes. The wall of the nanotubes consists of a helical array of the π-stacked graphene molecules. The inner and outer surfaces of the nanotubes are covered by hydrophilic triethylene glycol chains. Upon oxidation, the graphitic nanotubes become electroconductive. Modifications of the chemically accessible surface result in the formation of nanotubes with various properties.View full abstractDownload PDF (2742K) -
Ken Tanaka, Goushi Nishida, Takeshi Suda2007 Volume 65 Issue 9 Pages 862-873
Published: September 01, 2007
Released on J-STAGE: October 20, 2010
JOURNAL FREE ACCESSOur research group first demonstrated that cationic rhodium (I) complexes with BINAP-type bisphosphine ligands are versatile new catalysts for highly chemo-, regio-, and enantioselective [2+2+2] cycloadditions. Highly efficient catalytic synthesis of substituted benzenes, cyclophanes, and nitrogen heterocycles was achieved with high chemo- and regioselectivity using these catalysts. Enantioselective variants of these cycloadditions were also developed, which realized efficient catalytic constructions of axial, planar, and central chirality.View full abstractDownload PDF (1909K) -
Kazuyuki Miyashita, Masahiro Ikejiri, Tomoyuki Tsunemi, Ayumi Matsumot ...2007 Volume 65 Issue 9 Pages 874-887
Published: September 01, 2007
Released on J-STAGE: October 20, 2010
JOURNAL FREE ACCESSFostriecin (CI-920), isolated from Streptomyces pulveraceus, shows in vitro antitumor activity against leukemia, lung breast and ovarian cancer, and in vivo against L 1210 and P 388 leukemia. Its analogous compounds, such as leustroducsins, phoslactomycins and cytostatin, are also known to show a variety of biological activities. One of the most characteristic biochemical features is a specific inhibitory activity against Ser/Thr protein phosphatase 2 A. Not only because of their interesting biological activities, but also in order to prove utility of new reactions and/or new synthetic methodologies, fostriecin and its analogs attract much attention as a synthetic target, and a number of synthetic studies on these compounds have been conducted, particularly since the stereostructure of fostriecin was revealed by Boger's group in 1997. In this review, we focus on the studies reported after Shibasaki's review in 2005. Recent synthetic studies on the analogous natural products, leustroducsins, phoslactomycins and cytostatin are also included.View full abstractDownload PDF (1940K) -
Takeshi Kawase2007 Volume 65 Issue 9 Pages 888-896
Published: September 01, 2007
Released on J-STAGE: October 20, 2010
JOURNAL FREE ACCESSThe π-π interaction between curved conjugated systems is important for the formation and properties of new carbon materials such as carbon nanotubes, bucky onions and fullerene peapods. However, the nature has been little understood so far. Recently we have designed and synthesized cyclic [n] paraphenyleneacetylenes ([n] CPPAs) and the related compounds. They have smooth belt-shaped structures similar to a cut piece of carbon nanotubes, and thus may be termed “carbon nanorings”. The carbon nanorings having an appropriate cavity size form stable inclusion complexes with fullerenes in solution as well as in the solid state. The high affinity suggests that the considerably strong attractive interactions are operative between the curved conjugated systems. This review provides an insight into the noncovalent interaction between the concave and convex π surfaces.View full abstractDownload PDF (1509K) -
Naoki Asao, Kenichiro Sato2007 Volume 65 Issue 9 Pages 897-904
Published: September 01, 2007
Released on J-STAGE: October 20, 2010
JOURNAL FREE ACCESSGold-catalyzed formal [4+2] benzannulation between enynal or enynone units, including ortho-alkynyl (oxo) benzenes, and 2π-systems, such as alkynes and carbonyl compounds (enol forms), produces aromatic ketones in good to high yields. By simply changing the catalyst from gold to copper-Bronsted acid system, decarbonylated aromatic compounds can be prepared in the reactions using alkynes as the 2π-system. An efficient synthetic approach to angucyclinone antibiotics, (+) -ochromycinone and (+) -rubiginone B2, is developed by applying the present benzannulation to an intramolecular version. The reaction proceeds most probably through the formation of the benzo [c] pyrylium ate complex via the intramolecular nucleophilic addition of the carbonyl oxygen atom to the alkyne part of enynal or enynone units, which is induced by carbophilic gold catalyst.View full abstractDownload PDF (1262K) -
Kennosuke Itoh2007 Volume 65 Issue 9 Pages 905-906
Published: September 01, 2007
Released on J-STAGE: October 20, 2010
JOURNAL FREE ACCESSA biosynthetic pathway sometimes breathes new life into organic chemistry with its elegant mechanistic insight. Thiamine diphosphate (ThDP) is known as a coenzyme of transketolase and catalyze acyl anion transfer reactions in vivo by exploiting the concept of polarity reversal. The active catalyst for this biological transformation is N-heterocyclic carbene (NHC) generated from ThDP. Stetter reaction is one of the useful carbon-carbon bond forming reaction, which is induced by NHC. In this review, the enantioselective version of NHC catalyzed reactions, specialized in the intramolecular Stetter reaction and its related reactions are mentioned.View full abstractDownload PDF (345K) -
Mitsuhisa Yamano2007 Volume 65 Issue 9 Pages 907-913
Published: September 01, 2007
Released on J-STAGE: October 20, 2010
JOURNAL FREE ACCESSDownload PDF (1135K) -
[in Japanese], [in Japanese], [in Japanese], [in Japanese]2007 Volume 65 Issue 9 Pages 914
Published: September 01, 2007
Released on J-STAGE: October 20, 2010
JOURNAL FREE ACCESSDownload PDF (209K)
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