Papers - YAMAMURA Hatsuo
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Amphiphilic cyclodextrin derivatives with antibacterial activity: chemical mutation and structure-activity relationship Reviewed
Hatsuo Yamamura, Ayame Kato, Eri Yamada, Hisato Kato, Takashi Katsu, Kazufumi Masuda, Kayo Osawa, and Atsushi Miyagawa
New Journal of Chemistry 48 12355 - 12361 2024.07
Authorship：Lead author, Corresponding author Language：English Publishing type：Research paper (scientific journal)
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安全で抗菌性に優れた新規オリゴ糖誘導体—防腐効果のある化粧品原料の開発— Reviewed
小見宏幸，髙田健太，竹内彩乃，村上栞菜，宮川 淳，山村初雄
日本香粧品学会誌 48 ( 2 ) 82 - 88 2024.06
Authorship：Last author, Corresponding author Language：Japanese Publishing type：Research paper (scientific journal)
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One-step synthesis of sugar nucleotides under optimized conditions Reviewed
Kota Fujihara, Hatsuo Yamamura and Atsushi Miyagawa
Synthetic communications 54 ( 15 ) 1245 - 1251 2024.05
Language：English Publishing type：Research paper (scientific journal)
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Facile synthesis of β-1,3-glucan disaccharides using acyl protected glycosyl donors and acceptors prepared from 1,2:5,6-di-O-isopropylidene-α-D-glucofuranose Invited Reviewed
Atsushi Miyagawa, Ryusuke Tomita, Hatsuo Yamamura
24 ( 10 ) 69 - 78 2024.05
Authorship：Last author Language：English
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Atsushi Miyagawa, Nami Yamamoto, Ayane Ohno, Hatsuo Yamamura
International Journal of Biological Macromolecules 264 130546 2024.03
Authorship：Last author Language：English Publishing type：Research paper (scientific journal)
Other Link： https://www.sciencedirect.com/science/article/abs/pii/S0141813024013497
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Synthesis of cyclodextrin dimers via Diels–Alder reaction Reviewed
A. Miyagawa , T. Hasegawa, H. Yamamura
Synthetic Ccmmunications 53 ( 22 ) 1878 - 1885 2023.10
Authorship：Last author Language：English Publishing type：Research paper (scientific journal)
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Anti-bacterial ß-cyclodextrin derivatives inspired by the anti-microbial peptide polymyxin in order to better understand the role of single hydrophobic chain tail in selective anti-bacterial activity Reviewed
New Journal of Chemistry 47 10921 - 10929 2023.04
Authorship：Lead author, Corresponding author Language：English Publishing type：Research paper (scientific journal)
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Identification of a tomato UDP-arabinosyltransferase for airborne volatile reception Reviewed
K. Sugimoto, E. Ono, T. Inaba, T. Tsukahara, K. Matsui, M. Horikawa, H. Toyonaga, K. Fujikawa, T. Osawa, S. Homma, Y. Kiriiwa, Ippei Ohmura, Atsushi Miyagawa, Hatsuo Yamamura, M. Fujii, R. Ozawa, B.Watanabe, K. Miura, H. Ezura, T. Ohnishi, J. Takabayashi
Nature Communications 14 677 2023.02
Language：English Publishing type：Research paper (scientific journal)
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Synthesis of antimicrobial polymers with mannose residues for binding to the FimH adhesin of Escherichia coli Reviewed
Atsushi Miyagawa, Shinya Ohno, Hatsuo Yamamura
Journal of Polymer Science 2022.12
Authorship：Last author Language：English
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UDP glucose, cereblon dependent proinsulin degrader Reviewed
Cho, J.; Miyagawa, A.; Yamaguchi, K.; Abe, W.; Tsugawa, Y.; Yamamura, H.; Imai, T.
Scientific Reports 11 24516 2022.08
Language：English Publishing type：Research paper (scientific journal)
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UDP-glucose: A cereblon-dependent glucokinase Protein Degrader Reviewed
Cho, J.; Miyagawa, A.; Yamaguchi, K.; Abe, W.; Tsugawa, Y.; Yamamura, H.; Imai, T.
Int. J. Mol. Sci. 23 9094 2022.04
Language：English Publishing type：Research paper (scientific journal)
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Antimicrobial activities of amphiphilic cationic polymers and their efficacy of combination with novobiocin Reviewed
Miyagawa, A., Ohno, S., Hattori, T., Yamamura, H.
Journal of Biomaterials Science, Polymer Edition 22 299 - 312 2022.02
Authorship：Last author Publishing type：Research paper (scientific journal)
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Antibacterial Activity of Membrane-Permeabilizing Bactericidal Cyclodextrin Derivatives Reviewed
Hatsuo Yamamura, Tatsuya Hagiwara, Yuma Hayashi, Kayo Osawa, Hisato Kato, Takashi Katsu, Kazufumi Masuda, Ayumi Sumino, Hayato Yamashita, Ryo Jinno, Masayuki Abe, Atsushi Miyagawa
ACS Omega 6 ( 47 ) 31831 - 31842 2021.11
Publishing type：Research paper (scientific journal) Publisher：American Chemical Society (ACS)
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Antibacterial Activity of Membrane-permeabilizing Bactericidal Cyclodextrin Derivatives Reviewed International journal
Hatsuo Yamamura, Tatsuya Hagiwara, Yuma Hayashi, Kayo Osawa, Hisato Kato, Takashi Katsu, Kazufumi Masuda, Ayumi Sumino, Hayato Yamashita, Ryo Jinno, Masayuki Abe, Atsushi Miyagawa
ACS Omega 2021.11
Authorship：Lead author Language：English Publishing type：Research paper (scientific journal)
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Antimicrobial activities of amphiphilic cationic polymers and their efficacy of combination with novobiocin Reviewed International journal
Miyagawa, A., Ohno, S., Hattori, T., Yamamura, H
Journal of Biomaterials Science, Polymer Edition 2021.10
Language：English Publishing type：Research paper (scientific journal)
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N, N-Bis (hexyl α-d-acetylmannosyl) Acrylamide Reviewed International journal
Atsushi Miyagawa, Shinya Ohno, Hatsuo Yamamura
Molbank 2021 ( 3 ) M1255 2021.07
Language：English Publishing type：Research paper (scientific journal)
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One-Step Synthesis of Sugar Nucleotides Reviewed International journal
Atsushi Miyagawa, Sanami Toyama, Ippei Ohmura, Shun Miyazaki, Takeru Kamiya, Hatsuo Yamamura
J. Org. Chem. 85 15645 - 15651 2020.11
Language：English Publishing type：Research paper (scientific journal)
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Synthesis of β-1,3-glucan mimics by β-1,3-glucan trisaccharyl monomer polymerization Reviewed International journal
Atsushi Miyagawa, Hatsuo Yamamura
Carbohydrate Polymers 227 115105 2020.01
Language：English Publishing type：Research paper (scientific journal) Publisher：Elsevier Ltd
β-1,3-Glucans are important as immunostimulating agents in living organisms. The multivalent binding of β-1,3-glucans to dectin-1, a cell surface receptor, activates immunological defenses. To study artificial immunostimulating agents, glycopolymers carrying β-1,3-glucan trisaccharides as artificial ligands were synthesized. The β-1,3-glucan trisaccharide, defined as an active unit of β-1,3-glucan, was constructed from D-glucose by glycosylation. A norbornene group was introduced as a polymerizable group into the trisaccharide derivative at the aglycone. The prepared endo/exo norbornene stereoisomers of the monomers were separated by silica gel chromatography and identified by NMR spectroscopy and mass spectrometry. The synthesized glycosyl monomers were polymerized and copolymerized with norbornene using 2nd generation Hoveyda-Grubbs catalyst, deprotected, and purified by gel filtration to prepare water-soluble glycopolymers of varied compositions and high molecular weights. These polymers will have the potential for multivalent binding to dectin-1 to activate immune response and facilitate studies to understand the binding mechanisms of β-1,3-glucans with dectin-1.
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Gramicidin S-inspired antimicrobial cyclodextrin to disrupt gram-negative and gram-positive bacterial membranes. Reviewed International journal
Hatsuo Yamamura, Kana Isshiki, Yusuke Fujita, Hisato Kato, Takashi Katsu, Kazufumi Masuda, Kayo Osawa, Atsushi Miyagawa
MedChemComm 10 ( 10 ) 1432 - 1437 2019.08
Authorship：Lead author Language：English Publishing type：Research paper (scientific journal)
A membrane-active antimicrobial peptide gramicidin S-like amphiphilic structure was prepared from cyclodextrin. The mimic was a cyclic oligomer composed of 6-amino-modified glucose 2,3-di-O-propanoates and it exhibited antimicrobial activity against Gram-positive and Gram-negative bacteria, together with no resistance development and low haemolytic activity against red blood cells.
DOI： 10.1039/C9MD00229D
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Development of New Antimicrobial Agents from Cationic PG-surfactants containing oligo-Lys peptides Reviewed
Kimura Ryosuke, Shibata Masahide, Koeda Shuhei, Miyagawa Atsushi, Yamamura Hatsuo, Mizuno Toshihisa
Bioconjugate Chemistry 2018.12
Language：English Publishing type：Research paper (scientific journal)
Peptide gemini-surfactant (PG-surfactant), a kind of lipopeptide, is composed of a short linker peptide (X) between two alkyl-chain-modified Cys residues, and peripheral peptides at the N-terminal (Y) and the C-terminal (Z) sides, respectively, of the alkylated <br />
Cys residues. In this study, we developed and examined a series of PG-surfactants containing two C12 saturated alkanes and oligo-Lys, arranged at the X-, Y-, or Z-positions. To arrange oligo-Lys at the Y- or Z-positions, a repeat sequence of -Asp-Lys-Asp-Lys- <br />
was used at the X-position. All of the PG-surfactants exhibited high antimicrobial activity against both gram-positive and negative bacteria. In addition to high antimicrobial activity, a low hemolysis activity is prerequisite for efficient intravenous administration. <br />
Among the synthesized PG-surfactants, those having -(Lys)3- at the Y- or Z-positions, i.e. K3-DKDKC12 and DKDKC12-K3, showed reasonably low hemolytic activities. This combination of high antimicrobial activity along with low hemolytic activity is an <br />
essential and unique property, and has not been previously reported for the synthesized lipopeptides. Further, using scanning electron microscope (SEM) an -
Transglycosylation Activity of Catalytic Domain Mutant of Endo-1,3-β-glucanase from Cellulosimicrobium Cellulans Reviewed International journal
Y. Hantani, S. Motoki, A. Miyagawa, H. Yamamura, M.Oda
Protein & Peptide Letters 25 1 - 5 2018.07
Language：English Publishing type：Research paper (scientific journal)
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Membrane-Active Antimicrobial Poly(Amino-Modified Alkyl) beta-Cyclodextrins Synthesized via Click Reactions Reviewed International journal
Hatsuo Yamamura, Miho Nonaka, Shingo Okuno, Ryogo Mitsuhashi, Hisato Kato, Takashi Katsu, Kazufumi Masuda, Koichi Tanimoto,Haruyoshi Tomita, Atsushi Miyagawa
MedChemComm 9 509 - 518 2018.03
Authorship：Lead author Language：English Publishing type：Research paper (scientific journal)
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Membrane-active antimicrobial poly(amino-modified alkyl) β-cyclodextrins synthesized: Via click reactions Reviewed
Hatsuo Yamamura, Miho Nonaka, Shingo Okuno, Ryogo Mitsuhashi, Hisato Kato, Takashi Katsu, Kazufumi Masuda, Koichi Tanimoto, Haruyoshi Tomita, Atsushi Miyagawa
MedChemComm 9 ( 3 ) 509 - 518 2018
Language：English Publishing type：Research paper (scientific journal) Publisher：Royal Society of Chemistry
The emergence of drug-resistant bacteria has led to the high demand for new antibiotics. In this report, we investigated membrane-active antimicrobial β-cyclodextrins. These contain seven amino-modified alkyl groups on a molecule, which act as functional moieties to permeabilize bacterial cell membranes. The polyfunctionalization of cyclodextrins was achieved through a click reaction assisted by microwave irradiation. A survey using derivatives with systematically varied functionalities clarified the unique correlation of the antimicrobial activity of these compounds with their molecular structure and hydrophobicity/hydrophilicity balances. The optimum hydrophobicity for the compounds being membrane-active was specific to bacterial strains and animal cells
this led to specific compounds having selective toxicity against bacteria including multidrug-resistant pathogens. The results demonstrate that cyclodextrin is a versatile molecular scaffold for rationally designed structures and can be used for the development of new antibiotics.DOI： 10.1039/c7md00592j
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Syntheses and structure-membrane active antimicrobial activity relationship of alkylamino-modified glucose, maltooligosaccharide, and amylose Reviewed International journal
Hatsuo Yamamura, Takahiro Mabuchi, Tomoki Ishida, Atsushi Miyagawa
CHEMICAL BIOLOGY & DRUG DESIGN 90 ( 5 ) 1012 - 1018 2017.11
Authorship：Lead author Language：English Publishing type：Research paper (scientific journal) Publisher：WILEY
Antimicrobial alkylamine-modified sugars were prepared. Microwave-assisted click reaction efficiently achieved poly-functionalization of oligo- and polysaccharides. The sugars exhibited a unique relationship of their bacterial membrane permeabilization and antimicrobial activity with the number of functional groups and the structure of the molecular scaffold. It shows that the assembly of the functional groups is necessary for being antimicrobial. The amylose derivatives also exhibited synergy to minimize the necessary dose of conventional antibiotics and increase their antimicrobial potency.
DOI： 10.1111/cbdd.12989
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Chemical Synthesis and Isolation of UDP-2-Deoxy Glucose and Galactose Reviewed International journal
Atsushi Miyagawa, Shunya Takeuchi, Shinji Itoda, Sanami Toyama, Kenta Kurimoto, Hatsuo Yamamura,Yukishige Ito
Synthetic Communication 46 1790 - 1795 2016.08
Language：English Publishing type：Research paper (scientific journal)
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Aglycone Specificity of Endo-ß- 1,3-Glucanase Reviewed International journal
Atsushi Miyagawa, Takahiro Yamaguchi, Yoichi Tanabe, Masayuki Oda, Hatsuo Yamamura
JSM Chem 4 ( 2 ) 1026 2016.06
Language：English Publishing type：Research paper (scientific journal)
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2II-VII, 3I-VII, 6I-VII-Icosa-O-acetyl-2I-deoxy-cyclomaltoheptaose Reviewed International journal
Atsushi Miyagawa, Kazuki Kano, Aya Yoshida, Hatsuo Yamamura
Molbank ( 2 ) M900 2016.03
Language：English Publishing type：Research paper (scientific journal)
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Sialylation with systematically protected allyl galactoside acceptors using sialyl phosphate donors Reviewed International journal
Kenta Kurimoto, Hatsuo Yamamura, Atsushi Miyagawa
Tetrahedron Letters 57 1442 - 1445 2016.03
Language：English Publishing type：Research paper (scientific journal)
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Rule of Hydrophobicity/Hydrophilicity Balance in Membrane-Disrupting Antimicrobial Activity of Polyalkylamino Cyclodextrins Synthesized via Click Chemistry Reviewed International journal
Hatsuo Yamamura, Atsushi Miyagawa, Hiroki Sugiyama, Kensuke Murata, Takahiro Mabuti, Ryogo Mitsuhashi, Tatsuya Hagiwara, Miho Nonaka, Koichi Tanimoto, Haruyoshi Tomita
CHEMISTRYSELECT 1 ( 3 ) 469 - 472 2016.03
Language：English Publishing type：Research paper (scientific journal) Publisher：WILEY-V C H VERLAG GMBH
Emergence of drug-resistant bacterial pathogens and the concurrent demand for new antibiotics has led to membrane-active antimicrobial cyclodextrin (CD) development. CDs contain polyalkylamino groups; molecule polyfunctionalization was achieved via a click reaction. A survey using CDs with systematically varied functionalities clarified the unique correlation of their antimicrobial activity with the molecules' hydrophobicity/hydrophilicity balance. The optimum hydrophobicity of the membrane-active molecule was specific to bacterial strains and animal cells, leading to selective toxicity against bacteria including multidrug-resistant bacteria such as methicillin-resistant Staphylococcus aureus. The results demonstrate that CDs have a good molecular scaffold to pursue rationally designed structures with a desired activity for new antibiotic development.
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Sialylation with systematically protected allyl galactoside acceptors using sialyl phosphate donors Reviewed
Kenta Kurimoto, Hatsuo Yamamura, Atsushi Miyagawa
TETRAHEDRON LETTERS 57 ( 13 ) 1442 - 1445 2016.03
Language：English Publishing type：Research paper (scientific journal) Publisher：PERGAMON-ELSEVIER SCIENCE LTD
Various N-protected sialyl donors were synthesized and utilized in sialylation to investigate the reactivity and stereoselectivity of sialyl phosphate donors. Furthermore, in order to understand the effects of protecting groups and hydroxyl group positions on galactosyl acceptors, the sialylation efficiencies of all of the hydroxy groups on galactoses, which were protected with benzyl or benzoyl groups, were investigated. Consequently, the sialylation of N-acetyl-5-N,4-O-oxazolidinone-protected sialyl phosphate donors with allyl galactosides was accomplished and gave the GM4 regioisomers. (C) 2016 Elsevier Ltd. All rights reserved.
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Selective Deprotection of Trityl Group on Carbohydrate by Microflow Reaction Inhibiting Migration of Acetyl Group Reviewed International journal
Atsushi Miyagawa, Ryusuke Tomita, Kenta Kurimoto, Hatsuo Yamamura
Synthetic Communication 46 556 - 562 2016.02
Language：English Publishing type：Research paper (scientific journal)
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Functionalization of Aglycones on Sialoside Derivatives to Generate Precursors for Biological Applications Reviewed International journal
Kenta Kurimoto, Hatsuo Yamamura, Atsushi Miyagawa
CHEMISTRY LETTERS 45 ( 2 ) 128 - 130 2016.02
Language：English Publishing type：Research paper (scientific journal) Publisher：CHEMICAL SOC JAPAN
Sialic acid-containing glycans play numerous roles in various biological events. Fluorescent labeling and functional group transformation into versatile moieties are performed on synthesized galactose, sialyl galactose, and sialyl lactose derivatives to investigate carbohydrate-mediated biological functions. In this study, precursors for fluorescent labeling and viable substrates for investigations regarding carbohydrate mediated biological process were developed. Specifically, allyl galactosides and allyl sialosides were functionalized to produce functional precursors for biological applications.
DOI： 10.1246/cl.151003
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Selective deprotection of trityl group on carbohydrate by microflow reaction inhibiting migration of acetyl group Reviewed
Atsushi Miyagawa, Ryusuke Tomita, Kenta Kurimoto, Hatsuo Yamamura
SYNTHETIC COMMUNICATIONS 46 ( 6 ) 556 - 562 2016
Language：English Publishing type：Research paper (scientific journal) Publisher：TAYLOR & FRANCIS INC
The trityl group is an important and useful protecting group for primary hydroxy groups on carbohydrates. However, during deprotection, neighboring acetyl groups can easily migrate to the deprotected hydroxy groups. Hence, deprotection of trityl groups was optimized using a microreactor with regard to flow rate, reagent concentration, reaction time, and substrate concentration. The optimized microflow reaction conditions inhibited migration and could be applied to large-scale reactions and other substrates.
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Chemical synthesis and isolation of UDP-2-deoxy glucose and galactose Reviewed
Atsushi Miyagawa, Shunya Takeuchi, Shinji Itoda, Sanami Toyama, Kenta Kurimoto, Hatsuo Yamamura, Yukishige Ito
SYNTHETIC COMMUNICATIONS 46 ( 22 ) 1790 - 1795 2016
Language：English Publishing type：Research paper (scientific journal) Publisher：TAYLOR & FRANCIS INC
2-Deoxy sugars are attractive compounds in synthetic chemistry with regard to reactivity and stereoselectivity. Moreover, their ability to inhibit enzymes and metabolism is significant in biology. In this study, uridine-5-diphosphate (UDP)-2-deoxy glucose (11) and galactose (12) were synthesized chemically. These sugar donors for glycosyltransferases were obtained -selectively via phosphorylation using thioglycosides, coupling reaction with uridine-5-monophosphate (UMP)-morpholidate, and moderate deacetylation. Isolation was carried out by sequential silica-gel chromatography using two kinds of developing solvents in a refrigerator. The structures were elucidated from the NMR results. Investigation of stability showed that the synthesized UDP-2-deoxy sugars were hydrolyzed much faster in buffer (pH 4) than the natural UDP sugars.
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Synthesis of Branched Tetrasaccharide Derivatives of Schizophyllan-like β-Glucan Reviewed International journal
Atsushi Miyagawa, Tomoka Matsuda, Hatsuo Yamamura
Journal of Carbohydrate Chemistry 34 ( 5 ) 215 - 246 2015.07
Language：English Publishing type：Research paper (scientific journal) Publisher：Taylor and Francis Inc.
Branched tetrasaccharide derivatives as the repeating units of schizophyllan were synthesized using a common intermediate that had different protecting groups on the hydroxyl groups. Accordingly, β-1,3-disaccharide acceptors were efficiently glycosylated in a stepwise manner using monosaccharide donors to construct the branched tetrasaccharides. As a result, oligosaccharides with an internal branch rather than a branch on the terminal residue suitable for the synthesis of branched β-glucan were obtained.
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Polysulfonylated cyclodextrins. Part 14. Structural validation of tris- and pentakis(6-O-mesitylsulfony)cyclomaltooctaose isomers by 1H-NMR spectrometry Reviewed International journal
Hatsuo Yamamura, Mutsumi Watanabe, Sho Kawahara, Atsushi Miyagawa, and Masao Kawai
Magnetic Resonance in Chemistry 53 237 - 243 2015.03
Language：English Publishing type：Research paper (scientific journal)
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Polysulfonylated cyclodextrins. Part 14. Structural validation of tris-and pentakis(6-O-mesitylsulfony)cyclomaltooctaose isomers by H-1-NMR spectrometry Reviewed
Hatsuo Yamamura, Mutsumi Watanabe, Sho Kawahara, Atsushi Miyagawa, Masao Kawai
MAGNETIC RESONANCE IN CHEMISTRY 53 ( 3 ) 237 - 243 2015.03
Language：English Publishing type：Research paper (scientific journal) Publisher：WILEY-BLACKWELL
DOI： 10.1002/mrc.4165
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Chemical approach for the syntheses of GM4 isomers with sialic acid to non-natural linkage positions on galactose Reviewed International journal
Kenta Kurimoto, Hatsuo Yamamura, Atsushi Miyagawa
Carbohydrate Research 401 39 - 50 2015.01
Language：English Publishing type：Research paper (scientific journal)
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Chemical approach for the syntheses of GM4 isomers with sialic acid to non-natural linkage positions on galactose Reviewed
Kenta Kurimoto, Hatsuo Yamamura, Atsushi Miyagawa
CARBOHYDRATE RESEARCH 401 39 - 50 2015.01
Language：English Publishing type：Research paper (scientific journal) Publisher：ELSEVIER SCI LTD
Cell-surface glycans containing sialic acid are involved in various biological phenomena. However, the syntheses of GM4 derivatives with (2 >2) and (2 >4) linkages have not been investigated to date. In this study, sialylation of all of the hydroxyl groups on galactose were investigated for the syntheses of GM4 isomers. Regioselective sialylation was achieved via protection of galactosyl acceptors using electron-rich benzyl groups. These synthetic sialylated glycans will prove to be useful tools for studying unidentified carbohydrate-mediated biological roles. (C) 2014 Elsevier Ltd. All rights reserved.
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Synthesis of Antimicrobial Cyclodextrins Bearing Polyarylamino and Polyalkylamino Groups via Click Chemistry for Bacterial Membrane Disruption Reviewed
Hatsuo Yamamura他
Chem. Commun. 50 ( 41 ) 5444 - 5446 2014.05
Authorship：Lead author Language：English Publishing type：Research paper (scientific journal)
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Synthesis of antimicrobial cyclodextrins bearing polyarylamino and polyalkylamino groups via click chemistry for bacterial membrane disruption Reviewed
Hatsuo Yamamura, Yuuki Sugiyama, Kensuke Murata, Takanori Yokoi, Ryuji Kurata, Atsushi Miyagawa, Kenji Sakamoto, Keiko Komagoe, Tsuyoshi Inoue, Takashi Katsu
CHEMICAL COMMUNICATIONS 50 ( 41 ) 5444 - 5446 2014
Language：English Publishing type：Research paper (scientific journal) Publisher：ROYAL SOC CHEMISTRY
Cyclodextrin derivatives are synthesized as membrane-disrupting agents via a microwave-assisted Huisgen reaction. Their ability to permeabilize bacterial membranes depends on the amino substituents and an appropriate balance of hydrophobicity and hydrophilicity, thus enabling the preparation of derivatives with selective toxicity against bacteria.
DOI： 10.1039/c3cc49543d
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Unique, Fast, and All-or-none Click Reaction on Cyclodextrin and Amylose Reviewed
Yamamura Hatsuo, Miyagawa Atsushi
Chemistry Letters ( 6 ) 643 - 645 2013.06
Authorship：Lead author Language：English Publishing type：Research paper (scientific journal)
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Unique, Fast, and All-or-none Click Reaction on Cyclodextrin and Amylose Reviewed
Hatsuo Yamamura, Kyohei Shimohara, Ryuji Kurata, Yusuke Fujita, Kensuke Murata, Takaaki Hayashi, Atsushi Miyagawa
CHEMISTRY LETTERS 42 ( 6 ) 643 - 645 2013.06
Language：English Publishing type：Research paper (scientific journal) Publisher：CHEMICAL SOC JAPAN
The chemical polymodification of cyclodextrins and amyloses proceeded quickly with use of the microwave-assisted Huisgen reaction in an all-or-none fashion without the formation of less-modified by-products.
DOI： 10.1246/cl.130095
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Mimicking an antimicrobial peptide polymyxin B by use of cyclodextrin Reviewed
Hatsuo Yamamura, Ken Suzuki, Kazuma Uchibori, Atsushi Miyagawa, Masao Kawai, Chie Ohmizo, Takashi Katsu
CHEMICAL COMMUNICATIONS 48 ( 6 ) 892 - 894 2012.01
Language：English Publishing type：Research paper (scientific journal) Publisher：ROYAL SOC CHEMISTRY
Cyclodextrin derivatives prepared to mimic a membrane active antibacterial peptide polymyxin B strongly permeabilized bacterial membrane and inhibited bacterial proliferation.
DOI： 10.1039/c1cc16369h
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Mimicking an Antimicrobial Peptide Polymyxin B by Use of Cyclodextrin Reviewed
Hatsuo Yamamura, Atsushi Miyagawa,他
Chem. Commun. 48 ( 6 ) 892 - 894 2012
Authorship：Lead author Language：English Publishing type：Research paper (scientific journal)
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gamma-Cyclodextrins possessing an azido group and a triisopropylbenzenesulfonyl group as useful synthetic and authentic intermediates for unsymmetrically functionalized derivatives Reviewed
Yoshihide Himeno, Atsushi Miyagawa, Masao Kawai, Hatsuo Yamamura
TETRAHEDRON 65 ( 45 ) 9474 - 9480 2009.11
Language：English Publishing type：Research paper (scientific journal) Publisher：PERGAMON-ELSEVIER SCIENCE LTD
Seven isomers of cyclomaltooctaose (gamma-cyclodextrin) whose C6s were unsymmetrically disubstituted with both an azido group and an arenesulfonyloxy group were prepared and each of them was isolated by reversed phase chromatography. The assignment of the modified positions in each regioisomers was unambiguously performed by chemical correlation with the authentic compounds and chemical conversion to the 3,6-anhydro derivatives followed by high-resolution 2D-(1)H NMR (COSY, TOCSY, and HO-HAHA) analyses. The compounds are versatile synthetic and authentic intermediates to prepare sophisticated derivatives with two different functionalities at desired positions on the molecule for supramolecular chemistry. (C) 2009 Elsevier Ltd. All rights reserved.
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Preparation of a cyclodextrin dimer linked with a bis(picolinyl)cystine moiety and its intra- and intermolecular inclusion behavior Reviewed
Hatsuo Yamamura, Kousuke Satake, Rieko Hirasawa, Shinichi Yamada, Masao Kawai
JOURNAL OF INCLUSION PHENOMENA AND MACROCYCLIC CHEMISTRY 57 ( 1-4 ) 261 - 264 2007.04
Language：English Publishing type：Research paper (scientific journal) Publisher：SPRINGER
A novel cyclodextrin (CD) dimer linked with a bis(picolinyl)cystine (Cys) moiety was prepared by the coupling of Boc-protected Cys with amino-modified CDs, followed by deprotection of the Boc groups and bispicolinylation. The dimer showed less affinity to an organic guest molecule compared to that of a native CD monomer. It was attributed to an intramolecular inclusion of the pyridine moiety into CD cavity. The dimer caused significant increase of its organic guest affinity by an addition of a copper ion. The included pyridine group may come out of a CD cavity to bind the copper ion and the two CDs included cooperatively and intermolecularly a guest molecule with high affinity.
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Complexation and Chiral recognition Thermodynamics of g-Cyclodextrin with N-Acetyl- and N-Carbobenzyloxy-depetides Possessing Two Aromatic Rings Reviewed
Rekharsky, M. V.; Yamamura, H.; Kawai, M.; Inoue, Y.
J. Org. Chem 13 5228 - 5235 2003.04
Publishing type：Research paper (scientific journal)
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Preparation of Hexakis(6-O-mesitylsulfonyl)cyclomaltooctaoses and Structural Validation of the Four Isomers Using Heteronuclear Multiple Bond Correlation Spectroscopy Reviewed
Yamamura, H.; Miyachi, S.; Kano, K.; Araki, S.; Lee, K.; Kawai, M.; Ueyama, N.
Bull. Chem. Soc. Jpn 76 171 - 175 2003.04
Publishing type：Research paper (scientific journal)
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Preparation of b-Cyclodextrin Derivatives Possessing two Trimethylammonio Groups on Their Primary Hydroxy Sides as Chiral Selectors Reviewed
Yamamura , H.; Yamada, Y.; Mitagi, R.; Kano, K.; Araki, S.; Kawai, M.
J. Inclusion Phenom. Macrocyclic Chem 45 211 - 216 2003.04
Publishing type：Research paper (scientific journal)
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Extra Amino Group-containing Gramicidin S analogs PossessingOuter Membrane-permeabilizing Activ Reviewed
Kawai, M.; Tanaka, R.; Yamamura, H.; Yasuda, K.; Narita, S.; Umemoto, H.; Ando, S.; Katsu, T.
Chem. Commun 1264 - 1265 2003.04
Publishing type：Research paper (scientific journal)
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Cytotoxic Activity of Physalins Possessing modified Skeletal Structures against HeLa Cells Reviewed
Makino, B.; Ohya, J.; Yamamura, H.; Araki, S.; Butsugan, Y; Kawai, M.
Pharmazie 58 70 - 71 2003.04
Publishing type：Research paper (scientific journal)
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Preparation of beta-cyclodextrin derivatives possessing two trimethylammonio groups on their primary hydroxy sides as chiral guest selectors Reviewed
H Yamamura, Y Yamada, R Miyagi, K Kano, S Araki, M Kawai
JOURNAL OF INCLUSION PHENOMENA AND MACROCYCLIC CHEMISTRY 45 ( 3-4 ) 211 - 216 2003.04
Language：English Publishing type：Research paper (scientific journal) Publisher：SPRINGER
Three isomers of beta-cyclodextrin derivatives 2a-c possessing two trimethylammonio groups on their C(6) atoms were prepared by reaction of the corresponding regioisomers of diamino compounds with methyl iodide. These derivatives recognize chiral guests through three-point interactions composed of both Coulomb interactions by the two cationic moieties and hydrophobic interaction by the molecular cavity.
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Preparation of β-Cyclodextrin Derivatives Possessing Two Trimethylammonio Groups on Their Primary Hydroxy Sides as Chiral Guest Selectors Reviewed
Hatsuo Yamamura, Yuichi Yamada, Rie Miyagi, Kazuaki Kano, Shuki Araki, Masao Kawai
Journal of Inclusion Phenomena 45 ( 3-4 ) 211 - 216 2003.04
Language：English Publishing type：Research paper (scientific journal)
Three isomers of β-cyclodextrin derivatives 2a-c possessing two trimethylammonio groups on their C(6) atoms were prepared by reaction of the corresponding regioisomers of diamino compounds with methyl iodide. These derivatives recognize chiral guests through three-point interactions composed of both Coulomb interactions by the two cationic moieties and hydrophobic interaction by the molecular cavity.
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Extra amino group-containing gramicidin S analogs possessing outer membrane-permeabilizing activity Reviewed
M Kawai, R Tanaka, H Yamamura, K Yasuda, S Narita, H Umemoto, S Ando, T Katsu
CHEMICAL COMMUNICATIONS ( 11 ) 1264 - 1265 2003
Language：English Publishing type：Research paper (scientific journal) Publisher：ROYAL SOC CHEMISTRY
Novel (2S,4R)- and (2S,4S)-4-aminoproline residue-containing analogs of the cyclic decapeptide antibiotic gramicidin S were synthesized, which exhibited marked permeabilizing activity on the outer membrane of gram-negative bacteria.
DOI： 10.1039/b302351f
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Preparation of hexakis(6-O-mesitylsulfonyl)cyclomaltooctaoses and structural validation of the four isomers using heteronuclear multiple bond correlation spectroscopy Reviewed
Hatsuo Yamamura, Sadaichi Miyachi, Kazuaki Kano, Shuki Araki, Kenichi Lee, Masao Kawai, Norikazu Ueyama
Bulletin of the Chemical Society of Japan 76 ( 1 ) 171 - 175 2003
Language：English Publishing type：Research paper (scientific journal)
Four cyclomaltooctaose derivatives 1a-d, which possess six mesitylsulfonyloxy groups on their C(6) atoms, were prepared. The assignment of the regiosiomers was performed by observing the long-range coupling through a glycoside linkage between H(1′)-C(4) and C(1′)-H(4) using a heteronuclear multiple-bond correlation (HMBC) method.
DOI： 10.1246/bcsj.76.171
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Stereochemistry of Protected Ornithine Side Chains of Gramicidin S Derivatives: X-ray Crystal Structure of the Bis-Boc-tetra-N-methyl Derivative of Gramicidin S Reviewed
Yamada, K.; Unno, M.; Kobayashi, K.; Oku, H.; Yamamura, H.; Araki, S.; Matsumoto, H.; Katakai, R.; Kawai M.
J. Am. Chem. Soc 124 12684 - 12686 2002.04
Publishing type：Research paper (scientific journal)
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Cytotoxic Activity of Physalins and Related Compounds against HeLa Cells Reviewed
Kawai, M.; Makino, B.; Yamamura, H.; Araki, S.; Butsugan, Y.; Ohya, J.
Pharmazie 57 348 - 350 2002.04
Publishing type：Research paper (scientific journal)
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Tautomerism between Exomethylene Type Physalins and Oxymethylene-bridged Physalins Reviewed
Makino, B.; Kawai, M.; Yamamura, H.; Araki, B.; Butsugan, Y.
Pharmazie 57 215 - 216 2002.04
Publishing type：Research paper (scientific journal)
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Cytotoxic activity of physalins and related compounds against HeLa cells Reviewed
M. Kawali, B. Makino, H. Yamamura, S. Araki, Y. Butsugan, J. Ohya
Pharmazie 57 ( 5 ) 348 - 350 2002
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Tautomerism between exomethylene type physalins and oxymethylene-bridged physalins Reviewed
B. Makino, Masao Kawai, H. Yamamura, S. Araki, Y. Butsugan
Pharmazie 57 ( 3 ) 215 - 216 2002
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Shuki ARAKI, Hiromi HATTORI, Koji OGAWA, Masashi KUZUYA, Tomoko INOUE, Hatsuo YAMAMURA, Masao KAWAI
J. Chem. Soc., Perkin Trans.1 2476 - 2482 2001.04
Publishing type：Research paper (scientific journal)
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Critical Difference in Chiral Recognition of N-Cbz-D/L-aspartic and -glutamic Acids by Mono- and Bis(trimethylammonio)-beta-cyclodextrins. Reviewed
Mikhail REKHARSKY, Hatsuo YAMAMURA, Masao KAWAI, Yoshihisa INOUE
J. Am. Chem. Soc. 123 5360 - 5361 2001.04
Publishing type：Research paper (scientific journal)
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Capillary Zone Eelectrophoretic Chiral Discrimination Using Cationic Cyclodextrin Dderivative. Determination of Velocity andAssociation Constants of Each Enantiomer of Amino Acid Derivative with 6-Trimethylammonio-deoxy-beta-cyclodextrin Reviewed
Hatsuo YAMAMURA, Asako AKASAKI, Yuichi YAMADA, Kazuaki KANO, Takao Katsuhara, Shuki ARAKI, Masao KAWAI, Takao TSUDA
Electrophoresis 22 478 - 483 2001.04
Publishing type：Research paper (scientific journal)
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Calorimetric and NMR Studies on the Direct Correlation between Supramolecular Complex Structure and the Thermodynamics ofN-Benzyloxycarbonyl-L-aspartic and -glutamic Acids Inclusion with Mono- and Bis(trimethylammonio)-beta-cyclodextrins Reviewed
Hatsuo YAMAMURA, Mikhail REKHARSKY, Asako AKASAKI, Shuki ARAKI, Masao KAWAI, Yoshihisa INOUE
J. Phys. Org. Chem. 14 416 - 424 2001.04
Publishing type：Research paper (scientific journal)
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Allylindation of Cyclopropenes in Organic and Aqueous Media:Switching the Regio- and Stereoselectivity Based on the Chelation with aHydroxy Group and the Crystal Structure of the Cyclopropylindium Product Reviewed
Shuki ARAKI, Fumio SHIRAKI, Takashi TANAKA, Hiroyuki NAKANO, Kandasamy Subburaj, Tsunehisa HIRASHITA, Hatsuo YAMAMURA, MasaoKAWAI
Chem. Eur. J. 7 ( 13 ) 2784 - 2790 2001.04
Publishing type：Research paper (scientific journal)
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Tsunehisa HIRASHITA, Hatsuo YAMAMURA, Masao KAWAI, Shuki ARAKI
Chem. Commun. 387 - 388 2001.04
Publishing type：Research paper (scientific journal)
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Zinc Bromide-Promoted Tosylation of Alcohols Allows Efficient Temperature-Controlled Primary Hydroxy Sulfonylation Reviewed
Hatsuo YAMAMURA, Jyumpei KAWASAKI, Hirokazu SAITO, Shuki ARAKI, Masao KAWAI
Chem. Lett 706 - 708 2001.04
Publishing type：Research paper (scientific journal)
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The Structure of Physalin T from Physalis Alkekengi var. Francheti. Reviewed
Masao KAWAI, Tatsuo YAMAMMOTO, Bunsho MAKINO, Hatsuo YAMAMURA, Shuki ARAKI, Yasuo BUTSUGAN, Kazuki SAITO
J. Asian Natural Products Research 3 199 - 205 2001.04
Publishing type：Research paper (scientific journal)
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A new cascade for the one-pot synthesis of linear homoallylic alcohols with an allylic diindium reagent Reviewed
T Hirashita, H Yamamura, M Kawai, S Araki
CHEMICAL COMMUNICATIONS ( 4 ) 387 - 388 2001
Language：English Publishing type：Research paper (scientific journal) Publisher：ROYAL SOC CHEMISTRY
A new cascade based on a novel allylic diindium reagent has been developed; the indium reagent prepared from 3-bromo-1-iodopropene successively coupled with carbonyl compounds and then with aryl, alkenyl or allyl halides in the presence of a Pd(0) catalyst to afford a convenient one-pot synthesis of linear homoallylic alcohols.
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Zinc bromide-promoted tosylation of alcohols allows efficient temperature-controlled primary hydroxy sulfonylation Reviewed
Hatsuo Yamamura, Jyumpei Kawasaki, Hirokazu Saito, Shuki Araki, Masao Kawai
Chemistry Letters ( 7 ) 706 - 707 2001
Language：English Publishing type：Research paper (scientific journal) Publisher：Chemical Society of Japan
The combination of zinc bromide with tosyl chloride promoted sulfonylation, allowing temperature-controlled regioselective sulfonylation of carbohydrates which possess both primary and secondary hydroxy groups.
DOI： 10.1246/cl.2001.706
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The structure of physalin T from Physalis alkekengi var. francheti Reviewed
M Kawai, T Yamamoto, B Makino, H Yamamura, S Araki, Y Butsugan, K Saito
JOURNAL OF ASIAN NATURAL PRODUCTS RESEARCH 3 ( 3 ) 199 - 205 2001
Language：English Publishing type：Research paper (scientific journal) Publisher：HARWOOD ACAD PUBL GMBH
A new steroidal constituent named physalin T (3) was isolated from the aqueous extract of Physalis alkekengi var. francheti. Based on H-1 and C-13 NMR spectral studies the structure was assigned as 2,3-dihydrophysalin D, i.e., 5 alpha ,6 beta -dihydroxy-2,3,5,6-tetrahydrophysa B, which is the first example of a natural physalin possessing a saturated ring A moiety. The structure was confirmed by the chemical transformation from the known physalin D (2) to physalin T.
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The photochemical reactions of nitrogen-rich mesoionic 1,3-diphenyltetrazolium heterocycles and related compounds Reviewed
Shuki Araki, Hiromi Hattori, Koji Ogawa, Masashi Kuzuya, Tomoko Inoue, Hatsuo Yamamura, Masao Kawai
Journal of the Chemical Society. Perkin Transactions 1 1 ( 19 ) 2476 - 2482 2001
Language：English Publishing type：Research paper (scientific journal)
Photochemical reactions of azo and triazo derivatives of mesoionic 1,3-diphenyltetrazolium heterocycles and related compounds were studied. The reaction paths were found to depend markedly on the types of substrate, substituent and reaction solvent giving diverse products. Upon irradiation of the 1,1′3,3′-tetraphenylazoditetrazolium salt 1, the addition of hydrogen and acetone to the N-N bond was observed in methanol and acetone, respectively, whereas the bond was cleaved in diethyl ketone to give the 5-aminotetrazolium salt 10. The corresponding radical cation 11 also gave the reduction product in methanol. On the other hand, the 1,3-diphenyl-5-(phenylazo)tetrazolium salt 12 underwent nitrogen evolution giving the 1,3-diphenyltetrazolium salt 13 via the corresponding tetrazolium radical. Triazene derivatives 14 and 17 underwent an N–N bond cleavage to give tetrazolio-5-amide 4. The mesoionic triazene compounds bearing a tosyl 18 or cyano group 19 gave products 20 and 23. Triphenylphosphinotriazene 24 liberated nitrogen to give phosphinoimide 25 and its hydrolysis product 10. Tetrazolylamide 26 lost a phenyldiazonium group from the 1,3-diphenyltetrazolium ring to give the guanidine derivative 27. © 2001 The Royal Society of Chemistry.
DOI： 10.1039/b009526p
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Capillary zone electrophoretic chiral discrimination using a cationic cyclodextrin derivative: Determination of velocity and association constants of each enantiomer of the amino acid derivative with 6-trimethylammonio-deoxy-β-cyclodextrin Reviewed
Hatsuo Yamamura, Asako Akasaki, Yuichi Yamada, Kazuaki Kano, Takao Katsuhara, Shuki Araki, Masao Kawai, Takao Tsuda
Electrophoresis 22 ( 3 ) 478 - 483 2001
Language：English Publishing type：Research paper (scientific journal)
A positively charged β-cyclodextrin possessing a trimethylammonio group, 6-trimethylammonio-6-deoxy-β-cyclodextrin chloride 1 was prepared by the reaction of an amino derivative 3 with methyl iodide under very mild conditions. The cyclodextrin derivative discriminated between enantiomers of acetylphenylalanine 2 on capillary zone electrophoresis (CZE) analysis, which was possibly due to an electrostatic interaction between the trimethylammonio group of 1 and the carboxylate group of 2, and also due to the inclusion of 2 in a hydrophobic molecular cavity of 1. Double data normalization based on relative electrophoretic velocity of peaks due to indirect response of 1 and also water in an injected sample may be effective for elimination of variation and fluctuation of physical parameters of medium, such as viscosity and ionic strength, in order to determine intrinsic association constants and velocity of the complexes.
DOI： 10.1002/1522-2683(200102)22:3<478::AID-ELPS478>3.0.CO;2-L
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Calorimetric and NMR studies on the direct correlation between supramolecular complex structure and the thermodynamics of N-benzyloxycarbonyl-L-aspartic and -glutamic acid inclusion complexes with mono- and bis(trimethylammonio)-β-cyclodextrins Reviewed
Hatsuo Yamamura, Mikhail Rekharsky, Asako Akasaki, Schuki Araki, Masao Kawai, Yoshihisa Inoue
Journal of Physical Organic Chemistry 14 ( 7 ) 416 - 424 2001
Language：English Publishing type：Research paper (scientific journal)
The stability constants and standard Gibbs energy, enthalpy and entropy changes for the 1:1 inclusion complexation of N-benzyloxycarbonyl-L-aspartic and -glutamic acids with native β-cyclodextrin (β-CD), mono(6-amino-6-deoxy)-β-CD, mono(6-trimethylammonio-6-deoxy)-β-CD and A,B-, A,C- and A,D-bis(6-trimethylammonio-6-deoxy)-β-CDs were determined in aqueous phosphate buffer (pH 6.9) at 298.15 K by titration microcalorimetry. The supramolecular complex structures were elucidated from 1D and 2D NMR spectra, including ROESY, COSY and HOHAHA techniques. Combining the results obtained from the microcalorimetric and NMR studies, we elucidated not only the detailed complex structures and the thermodynamic consequences, but also the mutual dependence between the complex structure and the overall complexation thermodynamics. Copyright © 2001 John Wiley &
Sons, Ltd.DOI： 10.1002/poc.381
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Synthesis of New Tricyclic Mesoionic Amides via Photochemical Conversion of a 5-Azido-1-mesityl-3-phenyltetrazolium Salt Reviewed
Shuki ARAKI, Hiromi HATTORI, Hatsuo YAMAMURA, Masao KAWAI
J. Heterocyclic Chem. 37 1129 - 1134 2000.04
Publishing type：Research paper (scientific journal)
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Keiichi YAMADA, Yu-ichi TAKAHASHI, Hatsuo YAMAMURA, Shuki ARAKI, Masao KAWAI
J. Chem. Soc., Chem. Commun 1315 - 1316 2000.04
Publishing type：Research paper (scientific journal)
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A New Preparative Method for Allylic Indium (III) Reagents by Reductive Transmetalation of p-Allylpalladium (II) with Indium (I) Salts Reviewed
Shuki ARAKI, Toshiya KAMEI, Tsunehisa HIRASHITA, Hatsuo YAMAMURA, Masao KAWAI
Organic Lett 2 847 - 849 2000.04
Publishing type：Research paper (scientific journal)
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A Facile Preparation of Indium Enolates and Their Reformatsky-and Darzens-type Reactions Reviewed
Tsunehisa HIRASHITA, Kenji KINOSHITA, Hatsuo YAMAMURA, Masao KAWAI, Shuki ARAKI
J. Chem. Soc., Perkin Trans 1 825 - 828 2000.04
Publishing type：Research paper (scientific journal)
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A facile preparation of indium enolates and their Reformatsky- and Darzens-type reactions Reviewed
T Hirashita, K Kinoshita, H Yamamura, M Kawai, S Araki
JOURNAL OF THE CHEMICAL SOCIETY-PERKIN TRANSACTIONS 1 ( 5 ) 825 - 828 2000
Language：English Publishing type：Research paper (scientific journal) Publisher：ROYAL SOC CHEMISTRY
Indium enolates were readily prepared by transmetalation of lithium enolates with indium trichloride, and were subsequently reacted with aldehydes to give beta-hydroxy esters in high yields. Indium alpha-bromo enolates were also prepared and reacted with carbonyl compounds to give Darzens-type alpha,beta-epoxy carbonyl products.
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Phosphodiester bond cleavage mediated by a cyclic beta-sheet peptide-based dinuclear zinc(II) complex Reviewed
K Yamada, Y Takahashi, H Yamamura, S Araki, K Saito, M Kawai
CHEMICAL COMMUNICATIONS ( 14 ) 1315 - 1316 2000
Language：English Publishing type：Research paper (scientific journal) Publisher：ROYAL SOC CHEMISTRY
A dinuclear Zn(II) complex of N-2 delta,N-2 delta,N-2'delta,N-2'delta-tetrakis(2-pyridylmethyl) derivative of cyclic peptide gramicidin S markedly accelerated the cleavage of the phosphodiester linkage of the RNA model substrate 2-hydroxypropyl p-nitrophenyl phosphate.
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A facile preparation of indium enolates and their Reformatsky-and Darzens-type reactions Reviewed
Tsunehisa Hirashita, Kenji Kinoshita, Hatsuo Yamamura, Masao Kawai, Shuki Araki
Journal of the Chemical Society, Perkin Transactions 1 ( 5 ) 825 - 828 2000
Language：English Publishing type：Research paper (scientific journal)
Indium enolates were readily prepared by transmetalation of lithium enolates with indium trichloride, and were subsequently reacted with aldehydes to give β-hydroxy esters in high yields. Indium α-bromo enolates were also prepared and reacted with carbonyl compounds to give Darzens-type α,β-epoxy carbonyl products. © The Royal Society of Chemistry 2000.
DOI： 10.1039/a907334e
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Shuki ARAKI, Kaori YAMAMOTO, Tomoko INOUE, Koji FUJIMOTO, Hatsuo YAMAMURA, Masao KAWAI, Yasuo BUTSUGAN, Jinkui ZHOU, Emerich EICHHORN,Anton RIEKER, Martina HUBER
J. Chem. Soc., Perkin Trans. 2 985 - 995 1999.04
Publishing type：Research paper (scientific journal)
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Regioselective Allylation of Electron-deficient Alkenes with Organogallium and Organoindium Reagents Reviewed
Shuki ARAKI, Tomoaki HORIE, Motoshi KATO, Tsunehisa HIRASHITA, Hatsuo YAMAMURA, Masao KAWAI
Tetrahedron Lett. 40 2331 - 2334 1999.04
Publishing type：Research paper (scientific journal)
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Preparation of gamma-Heterosubstituted Allylindium and Diindium Reagents and Their Reactions with Carbonyl Compounds Reviewed
Tsunehisa HIRASHITA, Toshiya KAMEI, Tomoaki HORIE, Hatsuo YAMAMURA, Masao KAWAI, Shuki ARAKI
J. Org. Chem. 64 172 - 177 1999.04
Publishing type：Research paper (scientific journal)
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Preparation and Pproperties of Novel Gramicidin S Analogs Possessing a Tri-, Tetra- or Pentamethylene Bridge between Ornithine SideC.hains Reviewed
K. YAMADA, K. ANDO, Y. TAKAHASHI, Y. H. YAMAMURA, S. ARAKI, K. KOBAYASHI, R. KATAKAI, F. KATO, M. KAWAI
J. Peptide Res. 53 611 - 617 1999.04
Publishing type：Research paper (scientific journal)
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Hatsuo YAMAMURA, Shinichi YAMADA, Keiko KOHNO, Nozomi OKUDA, Shuki ARAKI, Kyoko KOBAYASHI, Ryoichi KATAKAI, Kazuaki KANO, MasaoKAWAI
J. Chem. Soc., Perkin Trans. 1 2943 - 2948 1999.04
Publishing type：Research paper (scientific journal)
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Hatsuo YAMAMURA, Daisuke Iida, Shuki ARAKI, Kyoko KOBAYASHI, Ryoichi KATAKAI, Kazuaki KANO, Masao KAWAI
J. Chem. Soc., Perkin Trans. 1 3111 - 3115 1999.04
Publishing type：Research paper (scientific journal)
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Photochemistry of Mesoionic Compounds. Photochemical Conversion of 5-Azido-1,3-diaryltetrazolium Aalts to Novel TricyclicMesoions with a Tetrazolo[1,5-a]benzimidazole Skelton Reviewed
Shuki ARAKI, Hiromi HATTORI, Noriyuki SHIMIZU, Koji OGAWA, Hatsuo YAMAMURA, Masao KAWAI
J. Heterocyclic Chem. 36 863 - 867 1999.04
Publishing type：Research paper (scientific journal)
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Optical Resolution and Absolute Configuration of N-Benzyloxycarbonyl-alpha-alkoxyglycines Reviewed
Masao KAWAI, Keiichi YAMADA, Kouji HOSODA, Yasuhiro OMORI, Shuji KATO, Nobuhiro NAGAYAMA, Seigo MASUI, Masao KAMIYA, HastuoYAMAMURA, Shuki ARAKI, Yasuo BUTSUGAN
Chirality 11 561 - 568 1999.04
Publishing type：Research paper (scientific journal)
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Convenient Preparation of [OrnTTfa]2- and [Orn(Boc)2,Orn(Tfa)2'] gramicidin S, Versatile Unsymmetrically Protected Derivatives ofGramicidin S Reviewed
K. YAMADA, K. ANDO, Y. TAKAHASHI, H. YAMAMURA, S. ARAKI, M. KAWAI
J. Peptide Res. 54 168 - 173 1999.04
Publishing type：Research paper (scientific journal)
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Chelation-controlled Regio- and Stereoselective Allylindation of Norbornenols Reviewed
Shuki ARAKI, Toshiya KAMEI, Yukimitsu IGARASHI, Tsunehisa HIRASHITA, Hatsuo YAMAMURA, Masao KAWAI
Tetrahedron Lett 40 7999 - 8002 1999.04
Publishing type：Research paper (scientific journal)
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Convenient preparation of [Orn(Tfa)2]- and [Orn(Boc)2, Orn(Tfa)2']gramicidin S, versatile unsymmetrically protected derivatives of gramicidin S Reviewed
K. Yamada, K. Ando, Y. Takahashi, H. Yamamura, S. Araki, M. Kawai
Journal of Peptide Research 54 ( 2 ) 168 - 173 1999
Language：English Publishing type：Research paper (scientific journal)
Treatment of gramicidin S (GS) with trifluoroacetic anhydride afforded a derivative in which only one of the two Orn side chains was trifluoroacetylated in 72% yield, furnishing the first efficient method for the preparation of a monoprotected derivative of GS. The mono(Tfa) derivative [Orn(Tfa)2]GS was treated with di-tert-butyl dicarbonate to yield dually protected derivative [Orn(Boc)2, Orn(Tfa)2']GS from which another monoprotected derivative [Orn(Boc)2]GS was prepared in high yield. These unsymmetrically protected GS derivatives are versatile starting materials for the preparation of various other GS derivatives. As an example of application of the unsymmetrically protected derivatives, a dimeric GS derivative was prepared via a singly p-nitrobenzenesulfonyl(NBS)-activated derivative [Orn(Boc)2,Orn(NBS)2']GS.
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Synthesis, electrochemical investigation and EPR spectroscopy of a reversible four-stage redox system based on mesoionic 5,5'-azinobis(1,3-diphenyltetrazole) and related mesoionic compounds Reviewed
Shuki Araki, Kaori Yamamoto, Tomoko Inoue, Koji Fujimoto, Hatsuo Yamamura, Masao Kawai, Yasuo Butsugan, Jinkui Zhou, Emerich Eichhorn, Anton Rieker, Martina Huber
Journal of the Chemical Society. Perkin Transactions 2 ( 5 ) 985 - 995 1999
Language：English Publishing type：Research paper (scientific journal) Publisher：Royal Society of Chemistry
Mesoionic 5,5'-azinobis(1,3-diphenyltetrazole) 1 was prepared, and its chemical oxidation gave stable crystals of the corresponding radical cation 1.+ and dication 12+, which reversibly gave back azine 1 on reduction with zinc. Electrochemical investigations of 1 using cyclovoltammetry and differential pulse voltammetry in pyridine (Py) or dichloromethane (DCM) also revealed the two reversible successive one-electron oxidations leading to dication 12+ via radical cation 1.+, both of which can be reduced to the neutral state 1. In the cathodic process, 1 was reduced by two consecutive one-electron transfers at only slightly different potentials up to the corresponding diamon 12- which could be re-oxidized to the neutral state
thus constituting a reversible four-stage redox system. Radical cation 1.+ and anion 1.- were characterized by EPR spectroscopy. In order to get more insights into the spin-density distribution of 1.+, the bis- and tetra-15N-labelled species 1a.+, 1b.+ and 1c.+ were synthesized and investigated by EPR and 15N as well as 14N ENDOR spectroscopy, revealing that the largest N hyperfine coupling constants are due to the nitrogen atoms of the central bridge. According to 1H ENDOR there seems to be a small coupling with the protons of both phenyl rings which cannot be resolved in the EPR spectrum. The electrochemical properties of the related mesoionic compounds 5-10 were also investigated in Py or DCM solutions. In the cathodic process, a reduction peak of 9 and 10 was observed due to their reversible one-electron reduction to the corresponding radical anions. The radical obtained on reduction of 10 was characterized by EPR spectroscopy. On the other hand, 5-8 can be reduced by a formal two-electron transfer up to the corresponding dianions which are re-oxidizable to the neutral state. In the anodic process, 9/10 undergo irreversible one-electron oxidations whereas 5/6 (in DCM) and 7/8 (in Py) experience reversible or irreversible step by step two-electron oxidations leading to the dications. In Py the oxidation products of 5/6 react to further species revealing two more oxidation and several rereduction peaks. On the other hand, the oxidation products of 7/8 are instable in DCM (one main oxidation and rereduction peak). The electrochemical data are discussed in terms of delocalization in the cations and conjugation in the dications.DOI： 10.1039/a809386e
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Preparation and properties of novel gramicidin S analogs possessing a tri-, tetra- or pentamethylene bridge between ornithine side chains Reviewed
K. Yamada, K. Ando, Y. Takahashi, Y. Oda, H. Yamamura, S. Araki, K. Kobayashi, R. Katakai, F. Kato, Masao Kawai
Journal of Peptide Research 53 ( 6 ) 611 - 617 1999
Language：English Publishing type：Research paper (scientific journal)
Gramicidin S (GS) analogs in which the N(δ) atoms of the two Orn side chains are linked by an oligomethylene bridge [-(CH2)(n)-
n=3-5] were prepared via the bis(p-nitrobenzenesulfonyl) derivative [Orn(NBS)(2,2')]GS. For comparison the nonbridged secondary amino group-containing analog [Orn(ME)(2,2')]GS was also prepared. 1H NMR and CD spectral analysis indicated that these analogs adopt the same β-sheet conformation as GS. The antimicrobial activities of these analogs were very similar, but were slightly dependent on the bridge chain length, the trimethylene-bridge analog being the most potent. -
Preparation and properties of novel gramicidin S analogs possessing a polymethylene bridge between ornithine side chains Reviewed
K Yamada, K Ando, Y Takahashi, H Yamamura, S Araki, M Kawai
PEPTIDE SCIENCE - PRESENT AND FUTURE 775 - 776 1999
Language：English Publishing type：Research paper (international conference proceedings) Publisher：SPRINGER
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Preparation and guest binding of novel β-cyclodextrin dimers linked with various sulfur-containing linker moieties t Reviewed
Hatsuo Yamamura, Shinichi Yamada, Keiko Kohno, Nozomi Okuda, Shuki Araki, Kyoko Kobayashi, Ryoichi Katakai, Kazuaki Kano, Masao Kawai
Journal of the Chemical Society - Perkin Transactions 1 ( 20 ) 2943 - 2948 1999
Language：English Publishing type：Research paper (scientific journal) Publisher：Royal Society of Chemistry
Novel cyclodextrin dimers (1, 2, 3 and 4) whose cyclodextrins were linked with sulfur-containing linkers, namely a thiodipropanamide, a dithiodipropanamide, a thiodiethanamide, or a dithiodiethanamide linker, were synthesized by a reaction of 6-amino-6-deoxycycIoheptaose 7 with the corresponding dicarboxylic acids. For their preparation, dicyclohexylcarbodiimide, l-(3-dimethylaminopropyl)-3-ethylcarbodiimideand(benzotriazol-l-yloxy) tripyrroIidinophosphonium hexafluorophosphate were examined as coupling reagents. 'H NMR studies of the dimers suggested an intramolecular inclusion of the linker moiety to the cyclodextrin cavity, which affected the complexation of guest molecules. Dimer 4 was converted to another type of dimer 5 by reductive cleavage of the disulfide bond to generate thiol group-containing mononieric species followed by a substitution reaction with 6-O-tosyl derivative 6. © The Royal Society of Chemistry 1999.
DOI： 10.1039/a905067a
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Polysulfonylated cyclodextrins. Part II.1 Preparation and structural validation of three isomeric pentakis(6-0-mesitylsulfonyl)cyclomaltoheptaoses f Reviewed
Hatsuo Yamamura, Daisuke Lida, Shuki Araki, Kyoko Kobayashi, Ryoichi Katakai
Journal of the Chemical Society - Perkin Transactions 1 ( 21 ) 3111 - 3115 1999
Language：English Publishing type：Research paper (scientific journal) Publisher：Royal Society of Chemistry
Three isomers of cyclomaltoheptaose derivatives, la-c, which possess five mesitylenesulfonyloxy groups on their C-6 atoms, were prepared. Assignment of the regiosiomers was performed by their conversion into compounds containing five 3,6-anhydroglucose units followed by 'H NMR analyses. The structures of the pentakis(3,6-anhydro) derivatives were also confirmed by their derivation from the known bis(TBDMS) derivatives. ©The Royal Society of Chemistry 1999.
DOI： 10.1039/a906436b
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Photochemistry of mesoionic compounds. Photochemical conversion of 5-azido-1,3-diaryltetrazolium salts to novel tricyclic mesoions with a tetrazolo[1,5-a]benzimidazole skeleton Reviewed
Shuki Araki, Hiromi Hattori, Noriyuki Shimizu, Koji Ogawa, Hatsuo Yamamura, Masao Kawai
Journal of Heterocyclic Chemistry 36 ( 4 ) 863 - 867 1999
Language：English Publishing type：Research paper (scientific journal) Publisher：HeteroCorporation
A new type of tetrazolium-5-amide mesoions 2 with a tricyclic tetrazolo[1,5-a]benzimidazole skeleton has been synthesized via photolysis of 5-azido-1,3-diaryltetrazolium salts 1.
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Optical resolution and absolute configuration of N-benzyloxycarbonyl-alpha-alkoxyglycines Reviewed
M Kawai, K Yamada, K Hosoda, Y Omori, S Kato, N Nagayama, S Masui, M Kamiya, H Yamamura, S Araki, Y Butsugan
CHIRALITY 11 ( 7 ) 561 - 568 1999
Language：English Publishing type：Research paper (scientific journal) Publisher：WILEY-LISS
Optical resolution of racemic N-benzyloxycarbonyl-protected alpha-alkoxy-glycines, (+/-)-Cbz-Gly(OR)-OH (R = Et and Pr-2), was achieved by means of fractional crystallization of diastereomeric salts with (+)-(1S,2S)-2-amino-1-phenyl-1,3-propanediol or diastereomeric esters of (+)- or (-)-menthol. The D- and L-configurations were assigned to the (+)- and (-)-Cbz-Gly(OR)-OH, respectively, based on L-enantioselective enzymatic hydrolysis of (+/-)-Cbz-Gly(OR)-OR' (R = Me, Et, and Pr-i; R' = CH2CF3 and Me) using porcine pancreatic lipase and papain. Chiroptical properties and HPLC retention times of D- and L-Gly(OR)-residue (R = Me and Pr-i)-containing peptides were compared in relation to their configurational assignments. (C) 1999 Wiley-Liss, Inc.
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Stereodivergent Allylindation of Cyclopropenes. Remarkable Stereodirection and Aaceleration by Neighbouring Carboxyl and HydroxylGroups Reviewed
Shuki ARAKI, Hiroyuki NAKANO, Kandasamy SUBBURAJ, Syunehisa HIRASHITA, Kensuke SHIBUTANI, Hastuo YAMAMURA, Masao KAWAI, YasuoBUTSUGAN
Tetrahedron Lett 39 6327 - 6330 1998.04
Publishing type：Research paper (scientific journal)
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Stereochemistry of Protected Ornithine Side Chains in Gramicidin D Derivatives and Their Resistance to N-Methylation Reviewed
Masao KAWAI, Tatsuo YAMAMOTO, Keiichi YAMADA, Masashi YAMAGUCHI, Shigehiro KUROBE, Hastuo YAMAMURA, Shuki ARAKI, Yasuo BUTSUGAN,Kyoko KOBAYASHI, Ryoichi KATAKAI, Kazuki SAITO, Terumi NAKAJIMA
Lett. Pept. Sci. 5 5 - 12 1998.04
Publishing type：Research paper (scientific journal)
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Hastuo YAMAMURA, Tadahiro YOTSUYA, Satoshi USAMI, Akihito IWASA, Shoji ONO, Yoshihisa TANABE, Daisuke IIDA, Takao KATSUHARA, KazuakiKANO, Testuo UCHIDA, Shuki ARAKI, Masao KAWAI
J. Chem. Soc., Perkin Trans. 1 1299 - 1303 1998.04
Publishing type：Research paper (scientific journal)
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Keiichi YAMADA, Hirotaka OZAKI, Naoki KANDAa, Hastuo YAMAMURA, Shuki Araki, Masao KAWAI
J. Chem. Soc., Perkin Trans. 1 3999 - 4004 1998.04
Publishing type：Research paper (scientific journal)
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Nitrogen-rich Mesoionic Compounds from 5-Chloro-1,3-diaryltetraazolium Salts and Nitrogen Nucleophiles. Synthesisand Properties of 5-Azido-1,3-diaryltetrazolium Salts Reviewed
Shuki ARAKI, Kaori YAMAMOTO, Misako YAGI, Tomoko INOUE, Hiroyo FUKUNAGA, Hiromi HATTORI, Hastuo YAMAMURA, Masao KAWAI, YasuoBUTSUGAN
Eur. J. Org. Chem. 121 - 127 1998.04
Publishing type：Research paper (scientific journal)
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Primary hydroxy-modified cyclomaltoheptaose derivatives with two kinds of substituents. Preparation of 6(I)-(benzyloxycarbonylamino)-, 6(I)-(tert-butoxycarbonylamino)- and 6(I)-azido-6(I)-deoxy-6(II),6(III),6(IV),6(V),6(VI),6(VII)-hexa-O-tosylcyclomaltoheptaose and their conversion to the hexakis-(3,6-anyhdro) derivatives Reviewed
H Yamamura, T Yotsuya, S Usami, A Iwasa, S Ono, Y Tanabe, D Iida, T Katsuhara, K Kano, T Uchida, S Araki, M Kawai
JOURNAL OF THE CHEMICAL SOCIETY-PERKIN TRANSACTIONS 1 ( 7 ) 1299 - 1303 1998.04
Language：English Publishing type：Research paper (scientific journal) Publisher：ROYAL SOC CHEMISTRY
Three cyclomaltoheptaoses (1, 2 and 3) which possess a benzyloxycarbonylamino group, a tert-butoxycarbonylamino group or an azido group, and six tosyloxy groups, on their C-6 atoms have been prepared. These can be versatile intermediates for the synthesis of derivatives possessing an amino group as well as other functional groups. As an example of their derivatization, their conversion to compounds containing 3,6-anhydroglucoses, which possess cation-binding abilities, is also reported.
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Stereochemistry of protected ornithine side chains in gramicidin S derivatives and their resistance to N-methylation Reviewed
Masao Kawai, Tatsuo Yamamoto, Keiichi Yamada, Masashi Yamaguchi, Shigehiro Kurobe, Hatsuo Yamamura, Shuki Araki, Yasuo Butsugan, Kyoko Kobayashi, Ryoichi Katakai, Kazuki Saito, Terumi Nakajima
Letters in Peptide Science 5 ( 1 ) 5 - 12 1998
Language：English Publishing type：Research paper (scientific journal) Publisher：Springer Netherlands
Derivatives of gramicidin S (GS) and its mono- and di-D-cyclohexylalanine (D-Cha) analogs possessing various protecting groups on Orn side chains were prepared. 1H NMR spectra of the unsymmetrically protected analogs [Orn(X)2,Orn(X′)2′,D-Cha4]GS were similar to the composites of the spectra of the symmetrical derivatives [Orn(X)2,2′,D-Cha4,4′]GS and [Orn(X′)2,2′]GS, revealing the proximity of the protecting groups of NδH of Orn residues at the 2 and 2′ positions to the side chains of D-Phe (or D-Cha) residues at the 4 and 4′ positions, respectively. The results indicated the presence of H-bonds between the NδH of Orn and the carbonyl of D-Phe residues in the i → i + 2 sense and not in i → i - 3, which was also supported by the ROESY analysis. The substantially strong H-bonds can explain the observed resistance of the urethane NH of the Orn side chains in the GS derivatives to the N-methylation with CH3I-Ag2O in DMF.
DOI： 10.1007/BF02443534
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Selective Reduction of Organic Functional Groups with Indium Hydride Reagents Reviewed
Masafumi YAMADA, Koji TANAKA, Yasuo BUTSUGAN, Masao KAWAI, Hastuo YAMAMURA, Shuki ARAKI
Main Group Metal Chemistry 20 ( 4 ) 241 - 246 1997.04
Language：English Publishing type：Research paper (scientific journal) Publisher：FREUND PUBLISHING HOUSE
New indium hydride reagents LiPhnInHe4-n (n = 0-2) were prepared and their reactivity and selectivity for various organic compounds containing representative functional groups were studied. It was shown that the reactivity can be controlled by changing the substituents and their number on the central indium atom. Their stereoselectivities were comparable to those of sodium borohydride and lithium aluminium hydride.
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High gamma-Selectivity in the Coupling of Penta-2,4-dienyl- and Pent-2-en-4-ynylindium Reagents with Aldehy Reviewed
Tsunehisa HIRASHITA, Shi'ichiro INOUE, Hastuo YAMAMURA, Masao KAWAI, Shuki ARAKI
J. Organometalic Chemistry 549 305 - 309 1997.04
Publishing type：Research paper (scientific journal)
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Diastereoselective Reduction of Acyclic Hydroxyketones and Diketones with an Indium Hydride Reagent Reviewed
Masafumi YAMADA, Tomoaki Horie, Masao KAWAI, Hastuo YAMAMURA, Shuki ARAKI
Tetrahedron 53 15685 - 15690 1997.04
Publishing type：Research paper (scientific journal)
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Convenient Enantioselective Preparation of Salsolinol-1-carboxylic Acid Reviewed
Masao KAWAI, Yulin Deng, Ikuko KIMURA, Hatsuo YAMAMURA, Shuki ARAKI, Makoto NAOI
Tetrahedron: Asymmetry 8 1487 - 1490 1997.04
Publishing type：Research paper (scientific journal)
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Assay for the (R)- and (S)-Enantiomers of Salsolinols in Biological Samples and Foods with Ion-pair High-performance liquidChromatography using beta-Cyclodextrin as a Chiral mobile Phase Additive Reviewed
Yulin Deng, Wakako MARUYAMA, Masao KAWAI, Philippe Dostert, Hatsuo YAMAMURA, Tsutomu TAKAHASHI, Makoto NAOI
J. Chromatography B. 689 313 - 320 1997.04
Publishing type：Research paper (scientific journal)
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Assay for the (R)- and (S)-Enantiomers of Salsolinols in Biological Samples and Foods with Ion-pair High-performance liquidChromatography using beta-Cyclodextrin as a Chiral mobile Phase Additive Reviewed
J. Chromatography B. 689 313 - 320 1997.04
Publishing type：Research paper (scientific journal)
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Selective reduction of organic functional groups with indium hydride reagents Reviewed
Masafumi Yamada, Koji Tanaka, Yasuo Butsugan, Masao Kawai, Hatsuo Yamamura, Shuki Araki
Main Group Metal Chemistry 20 ( 4 ) 241 - 246 1997
Language：English Publishing type：Research paper (scientific journal) Publisher：Walter de Gruyter GmbH
New indium hydride reagents LiPhnInH4-n (n = 0-2) were prepared and their reactivity and selectivity for various organic compounds containing representative functional groups were studied. It was shown that the reactivity can be controlled by changing the substituents and their number on the central indium atom. Their stereoselectivities were comparable to those of sodium borohydride and lithium aluminium hydride.
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Mechanism of enantioseparation of salsolinols, endogenous neurotoxins in human brain, with ion-pair chromatography using beta-cyclodextrin as a mobile phase additive Reviewed
YL Deng, W Maruyama, H Yamamura, M Kawai, P Dostert, M Naoi
ANALYTICAL CHEMISTRY 68 ( 17 ) 2826 - 2831 1996.09
Language：English Publishing type：Research paper (scientific journal) Publisher：AMER CHEMICAL SOC
A novel method for direct separation of the enantiomers of salsolinol and N-methylsalsolinol was devised, The enantiomers were completely separated with ion-pair chromatography on a reversed-phase column with beta-cyclodextrin as a chiral mobile phase additive and sodium 1-heptanesulfonate as a counterion. The mechanism for enantioseparation with this ion-pair system containing a-cyclodextrin was discussed, The effects of beta-cyclodextrin, counterions, pH, ionic strength, and organic solvent on retention were investigated, and a retention model was proposed and proved to be consistent with the experimental data. A preliminary study of the enantiomeric composition of salsolinol and N-methylsalsolinol in banana and in human brain was made as an example of the application of this assay.
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Structural Revision of Physalin H Isolated from Physalis anguluta Reviewed
Bunsho MAKINO, Masao KAWAI, Toichi OGURA, Masaki NAKANISHI, Hatsuo YAMAMURA, Yasuo BUSTUGAN
J. Natural Products 58 1668 - 74 1996.04
Publishing type：Research paper (scientific journal)
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Preparation of Protected alpha-Alkoxyglycines. Reviewed
Masao KAWAI, Kouji HOSODA, Yoshimasa Omori, Keiichi YAMADA, Shiko HAYAKAWA, Hatsuo YAMAMURA, Yasuo BUSTUGAN
Synthetic Communications 26 1545 - 1554 1996.04
Publishing type：Research paper (scientific journal)
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Mechanism of Enantioseparation of Salsolinols, Endogenous Neurotoxins in Human Brain, with Ion-Pair Chromatography Usingbeta-Cyclodextrin as a Mobile Phase Additive. Reviewed
Yulin Deng, Wakako MARUYAMA, Hatsuo YAMAMURA, Masao KAWAI, Philippe Dostert, Makoto NAOI
Anal. Chem. 68 2826 - 2831 1996.04
Publishing type：Research paper (scientific journal)
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Indium-mediated Reaction of 1,3-Dichloro- and 1,3-Dibromopropens with Carbonyl Compounds. Generation of Novel 3,3-Diindiopropene. Reviewed
Shuki ARAKI, Tsunehisa HIRASHITA, Hidetaka SHIMIZU, Hatsuo YAMAMURA, Masao KAWAI, Yasuo BUTSUGAN
Tetrahedron Lett. 37 8417 - 8420 1996.04
Publishing type：Research paper (scientific journal)
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Dependence of Guest-binding Ability on Cavity Shape of Deformed Cyclodextrins. Reviewed
Kahee FUJITA, Yuji OKABE, Kazuko OHTA, Hatsuo YAMAMURA, Tsutomu TAHARA, Yasuyoshi NOGAMI, Toshitaka KOGA
Tetrahedron Lett. 37 1825 - 1828 1996.04
Publishing type：Research paper (scientific journal)
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A Cyclodextrin Derivative with Cation Carrying Ability: Heptakis(3,6-anhydro)-beta-cyclodextrin 2-O-p-Phenylazobenzoate. Reviewed
Hatsuo YAMAMURA, Hirotake KAWAI, Tadahiro YOTSUYA, Tamotsu HIGUCHI, Yasuo BUTSUGAN, Shuki ARAKI, Masao KAWAI, Kahee FUJITA
Chem. Lett. 799 - 780 1996.04
Publishing type：Research paper (scientific journal)
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Hatsuo YAMAMURA, Hideki MASUDA, Yoshitaka KAWASE, Masao KAWAI, Yasuo BUTSUGAN, Hisahiko EINAGA
J. Chem. Soc., Chem. Commun. 1069 - 1079 1996.04
Publishing type：Research paper (scientific journal)
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Upon 'Physalin L' Isolated from Physalis minima Reviewed
Masao KAWAI, Bunsho MAKINO, Hatsuo YAMAMURA, Yasuo BUTSUGAN
Phytochemistry 43 661 - 663 1996.04
Publishing type：Research paper (scientific journal)
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A cyclodextrin derivative with cation carrying ability: Heptakis(3,6-anhydro)-beta-cyclodextrin 2-O-p-phenylazobenzoate Reviewed
H Yamamura, H Kawai, T Yotsuya, T Higuchi, Y Butsugan, S Araki, M Kawai, K Fujita
CHEMISTRY LETTERS ( 9 ) 799 - 800 1996
Language：English Publishing type：Research paper (scientific journal) Publisher：CHEMICAL SOC JAPAN
A cation-complexing host, heptakis(3,6-anhydro)-beta-cyclodextrin, was converted to a mono-p-phenylazobenzoyl derivative, which exhibited alkali metal-carrying ability in CH2Cl2-H2O system.
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X-Ray crystallographic study of octakis(3,6-anhydro)-γ-cyclodextrin with a highly specific cation binding ability Reviewed
Hatsuo Yamamura, Hideki Masuda, Yoshitaka Kawase, Masao Kawai, Yasuo Butsugan, Hisahiko Einaga
Chemical Communications ( 9 ) 1069 - 1070 1996
Language：English Publishing type：Research paper (scientific journal) Publisher：Royal Society of Chemistry
Octakis(3,6-anhydro)-γ-cyclodextrin, which is composed of eight 3,6-anhydroglucoses, is analysed by X-ray crystallography to determine its unique structure which contains a hydrophilic cavity enabling specific binding to Cs+.
DOI： 10.1039/CC9960001069
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Upon 'physalin L' isolated from Physalis minima Reviewed
Masao Kawai, Bunsho Makino, Hatsuo Yamamura, Yasuo Butsugan
Phytochemistry 43 ( 3 ) 661 - 663 1996
Language：English Publishing type：Research paper (scientific journal) Publisher：Elsevier Ltd
5α-Ethoxy-6β-hydroxy- and 6β-ethoxy-5α-hydroxy-5,6-dihydrophysalin B were derived from the corresponding 5β,6β- and 5α,6α-epoxides, respectively, by acid treatment in ethanol. The 5α-ethoxy derivative was isolated as an artefact from Physalis alkekengi, while other workers isolated the 6β-ethoxy compound as a constituent of P. minima and mistakenly named it as physalin L, which had already been assigned to (25S)-3,4-didehydro- 2,3,25,27-tetrahydrophysalin A. The 1H NMR spectrum of the 6β-ethoxy derivative prepared by us, however, did not agree with the reported data.
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Studies on the construction of allosteric model peptides carrying beta-cyclodextrin and picolylamino or picolynylamino group Reviewed
H Yamamura, M Kawai, R Hirasawa, K Yamada, Y Butsugan
PEPTIDE CHEMISTRY 1995 533 - 536 1996
Language：English Publishing type：Research paper (international conference proceedings) Publisher：PROTEIN RESEARCH FOUNDATION
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Preparation of protected alpha-alkoxyglycines Reviewed
M Kawai, K Hosoda, Y Omori, K Yamada, S Hayakawa, H Yamamura, Y Butsugan
SYNTHETIC COMMUNICATIONS 26 ( 8 ) 1545 - 1554 1996
Language：English Publishing type：Research paper (scientific journal) Publisher：MARCEL DEKKER INC
N-Carbobenzoxy-alpha-alkoxyglycine esters were synthesized by H2SO4-catalyzed O-alkylation of N-carbobenzoxy-alpha-hydroxyglycine and also by base treatment of N-carbobenzoxy-N-chloroglycine methyl ester in the corresponding alcohol. Saponification of the protected alpha-alkoxyglycines gave free acids which can be used for the synthesis of alpha-alkoxyglycine residue-containing peptides.
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2 ALTERNATIVE CONFORMATIONAL STATES OF ALPHA,ALPHA-DIALKYLGLYCYL-L-PROLYL SEQUENCES GOVERNED BY PRESENCE ABSENCE OF AN NH GROUP DIRECTLY FOLLOWING THE PROLINE RESIDUE, X-RAY CRYSTAL AND MOLECULAR-STRUCTURES OF BOC-D-IVA-L-PRO-NHBZL AND BOC-L-IVA-PRO-NHBZL Reviewed
M KAWAI, Y OMORI, H YAMAMURA, Y BUTSUGAN, T TAGA, Y MIWA
JOURNAL OF THE CHEMICAL SOCIETY-PERKIN TRANSACTIONS 1 ( 17 ) 2115 - 2122 1995.09
Language：English Publishing type：Research paper (scientific journal) Publisher：ROYAL SOC CHEMISTRY
The crystal structures of the isovaline-containing dipeptides, Boc-D-Iva-L-Pro-NHBzl 4 and Boc-L-Iva-L-Pro-NHBzl 5 were determined by X-ray diffraction. The diastereoisomeric peptides adopt intramolecular hydrogen-bonded beta-turn conformations closely similar to each other (4:phi(Iva) -51 degrees, psi(Iva) -38 degrees, phi(Pro) - 70 degrees and psi(Pro) -17 degrees and 5:phi(Iva) -53 degrees, psi(Iva) -35 degrees, phi(Pro) -72 degrees and psi(Pro) -14 degrees). The Pro ring of each peptide is in CY-exo conformation. These conformations are essentially the same as those in the reported crystal structures of the Aib-L-Pro sequence possessing an NH group directly attached to the carbonyl of the L-Pro, indicating that replacement of either one of the two methyl groups of the Aib moiety with an ethyl group does not cause any significant change in the beta-turn conformation of the Aib-L-Pro sequence in the crystalline state.
CD spectral analysis of the terminal chromophoric group-carrying peptides Dnp-Gly-X-L-Pro-Gly-pNA (X = Aib 6 and D/L-Iva 7/8) has shown that these three tetrapeptides in CHCl3 and THF solutions also adopt a beta-turn-type conformation. CD spectra of glycolic acid residue-containing analogues in place of the fourth Gly residue revealed a lack of beta-turn tendency in these analogues, indicating the importance of intramolecular hydrogen bonding for the beta-turn conformation of the central dipeptide moieties. The results are consistent with the reported unturned crystal structures of Aib-L-Pro and D/L-Iva-L-Pro sequence-containing peptides tacking the NH group which directly follows the Pro residue available for intramolecular hydrogen bonding. -
Masao KAWAI, Yoshimasa OMORI, Hatsuo YAMAMURA, Yasuo BUSTUGAN, Yoshihisa MIWA
J. Chem. Soc. Perkin Trans. 1 2115 - 2122 1995.04
Publishing type：Research paper (scientific journal)
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Synthesis of a 'Head-to-tail' Type Cyclodextrin Dimer Linked by a Disulfide Bridge Reviewed
Yuji OKABE, Hatsuo YAMAMURA, Kei-ichi OBE, Kazuko OHTA, Masao KAWAI, Kahee FUJITA
J. Chem. Soc., Chem. Commun. 581 - 582 1995.04
Publishing type：Research paper (scientific journal)
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Synthesis and Alkali Metal Ion Binding of Poly(3,6-anhydro)-alpha-cyclodextrins Reviewed
Hatsuo YAMAMURA, Hideki NAGAOKA, Masao KAWAI, Yasuo BUTSUGAN, Kahee FUJITA
Tetrahedron Lett. 36 1093 - 1094 1995.04
Publishing type：Research paper (scientific journal)
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Structural Revision of Physalin H Isolated from Physalis anguluta Reviewed
J. Natural Products 58 1668 - 74 1995.04
Publishing type：Research paper (scientific journal)
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Physalins Possessing an Endoperoxy Structure from Physalis Alkekengi var. francheti. Structural Revision of Physalin K. Reviewed
Busho MAKINO, Masao KAWAI, Yasushi IWATA, Hatsuo YAMAMURA, Yasuo BUTSUGAN, Kiyoshi OGAWA, Mitsuo HAYASHI
Bull. Chem. Soc. Jpn. 68 219 - 226 1995.04
Publishing type：Research paper (scientific journal)
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New Physalins Possessing an Additional Carbon-carbon-bond from Physalis alkekengi var. francheti. Reviewed
Bunsho MAKINO, Masao KAWAI, Koji KITO, Hatsuo YAMAMURA, Yasuo BUSTUGAN
Tetrahedron 51 12529 - 12538 1995.04
Publishing type：Research paper (scientific journal)
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PHYSALINS POSSESSING AN ENDOPEROXY STRUCTURE FROM PHYSALIS-ALKEKENGI VAR FRANCHETI - STRUCTURAL REVISION OF PHYSALIN-K Reviewed
B MAKINO, M KAWAI, Y IWATA, H YAMAMURA, Y BUTSUGAN, K OGAWA, M HAYASHI
BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 68 ( 1 ) 219 - 226 1995
Language：English Publishing type：Research paper (scientific journal) Publisher：CHEMICAL SOC JAPAN
Physalin K was isolated from Physalis alkekengi var. francheti. Spectroscopic studies and chemical correlations, however, revealed that the reported structure of physalin K at the AB ring moiety, namely, 4 alpha,5 alpha-epoxy-6 alpha-hydroxy-2-en-1-one, should be revised to 2 alpha,5 alpha-epidioxy-6 beta-hydroxy-3-en-1-one. A new physalin,named physalin Q, was also isolated and identified as the 2 beta,5 beta-epidioxy diastereomer of physalin K.
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Synthesis of a 'head-to-tail' type cyclodextrin dimer linked by a disulfide bridge Reviewed
Yuji Okabe, Hatsuo Yamamura, Ken-Ichi Obe, Kazuko Ohta, Masao Kawai, Kahee Fujita
Journal of the Chemical Society, Chemical Communications ( 5 ) 581 - 582 1995
Language：English Publishing type：Research paper (scientific journal)
A 'head-to-tail' type cyclodextrin dimer, where C-3 of one cyclodextrin and C-6 of the other are linked by a disulfide bond, is synthesized using 2,2′-dipyridyl disulfide, which is widely applicable to the preparation of other dimers.
DOI： 10.1039/C39950000581
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Crystal Structures of 5a,6a-Epoxy and 2,3-Dihydro Derivatives of Physalin B, a 13,14-seco-16,24-Cyclosteroid, and Their 1HNMR SpectralAnalysis Reviewed
Masao KAWAI, Bunsho MAKINO, Tooru TAGA, Yoshihisa MIWA, Tatsuo YAMAMOTO, Tsunehiro FURUTA, Hatsuo YAMAMURA, Yasuo BUTSUGAN, KiyoshiOGAWA, Mitsuo HAYASHI
Bull. Chem. Soc. Jpn. 67 222 - 226 1994.04
Publishing type：Research paper (scientific journal)
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Crystal structures of 5α,6α-epoxy and 2,3-dihydro derivatives of physalin B, a 13,14-seco-16,24-cyclosteroid, and their 1H NMR spectral analysis Reviewed
M. Kawai, B. Makino, T. Taga, Y. Miwa, T. Yamamoto, T. Furuta, H. Yamamura, Y. Butsugan, K. Ogawa, M. Hayashi
Bulletin of the Chemical Society of Japan 67 ( 1 ) 222 - 226 1994
Language：English Publishing type：Research paper (scientific journal) Publisher：Chemical Society of Japan
X-Ray crystallographic analysis of two steroid derivatives, 5α,6α-epoxyphysalin B and 2,3-dihydrophysalin B, have been undertaken, revealing their closely similar crystal structures to each other. Their 1H NMR spectra, as well as that of the parent compound physalin B, a 13,14-seco-16,24-cyclosteroid from Physalis alkekengi, have been analyzed based on the crystal structures of these derivatives.
DOI： 10.1246/bcsj.67.222
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CRYSTAL-STRUCTURES OF BOC-D-PRO-OBZL AND L-IVA-L-PRO-OBZL - UNTURNED CONFORMATION OF AIB-PRO SEQUENCE UNAFFECTED BY REPLACEMENT OF ME WITH ET IN AIB Reviewed
M KAWAI, Y OMORI, H YAMAMURA, Y BUTSUGAN, T TAGA, Y MIWA
BIOPOLYMERS 33 ( 8 ) 1207 - 1212 1993.08
Language：English Publishing type：Research paper (scientific journal) Publisher：JOHN WILEY & SONS INC
The crystal structures of the isovaline (Iva) containing dipeptides, Boc-D-Iva-L-Pro-OBzl and Boc-L-Iva-L-Pro-OBzl, were determined by x-ray diffraction. The diastereomeric peptides were shown to adopt unturned conformations closely similar to each other (phi(Iva) 52-degrees, psi(Iva) 46-degrees, phi(Pro) -65-degrees, and phi(Pro) 143-degrees for D-Iva-L-Pro sequence and phi(Iva) 52-degrees, ps(Iva) 44-degrees, phi(Pro) -63-degrees, and psi(Pro) 148-degrees for L-IVa-L-Pro sequence). The Pro ring of each peptide was in C(gamma)-endo conformation. The unusually large angle C(Iva)-N(Pro)-C(Pro)delta values (131-degrees in both peptides) were observed, that was due to steric repulsion between the delta-methylene of Pro and the alkyl side chain of Iva residue. These conformations were essentially the same as that of the corresponding alpha-aminoisobutyric acid (Aib) -containing peptide Boc-Aib-L-Pro-OBzl. The result has demonstrated that replacement of either one of the two methyl groups of the Aib residue in Boc-Aib-L-Pro-OBzl with an ethyl group does not cause any significant change in the unturned conformation of the dipeptide. (C) 1993 John Wiley & Sons, Inc.
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Preparation of Polytosylated gamma-Cyclodextrins. Reviewed
Hatsuo YAMAMURA, Yoshitaka KAWASE, Masao KAWAI, Yasuo BUTSUGAN
Bull. Chem. Soc. Jpn. 66 ( 2 ) 585 - 588 1993.04
Language：English Publishing type：Research paper (scientific journal) Publisher：The Chemical Society of Japan
Practical preparation of polytosylated <i>γ</i>-cyclodextrins, octakis(6-<i>O</i>-tosyl)-2-<i>O</i>-tosyl-<i>γ</i>-cyclodextrin, octakis(6-<i>O</i>-tosyl)-<i>γ</i>-cyclodextrin, and heptakis(6-<i>O</i>-tosyl)-<i>γ</i>-cyclodextrin, has been established. The procedure involves reaction of <i>γ</i>-cyclodextrin with tosyl chloride in pyridine and column chromatographic separation using silica gel modified with 3-aminopropyl groups.
DOI： 10.1246/bcsj.66.585
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Hatsuo YAMAMURA, Toshishige EZUKA, Yoshitaka KAWASE, Masao KAWAI, Yasuo BUTSUGAN, Kahee FUJITA
J. Chem. Soc., Chem. Commun. ( 7 ) 636 - 637 1993.04
Language：English Publishing type：Research paper (scientific journal) Publisher：ROYAL SOC CHEMISTRY
Octakis(3,6-anhydro)-gamma-cyclodextrin 3 has been prepared by the reaction of octakis(6-O-tosyl)-gamma-cyclodextrin with KOH; 3 shows a specific binding ability to alkali metal ions with larger ionic diameters, owing to its hydrophilic cavity which is similar to the layered crown ethers.
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Determination of the Structures of Tris(6-O-mesitylenesulfonyl)-alpha-cyclodextrin Regioisomers by 1H NMRAnalyses of the Corresponding 3,6-Anhydrocyclodextrin Derivatives. Reviewed
Hatsuo YAMAMURA, Hideki NAGAOKA, Kazuki SAITO, Masao KAWAI, Yasuo BUTSUGAN
J. Org. Chem. 58 2936 - 2937 1993.04
Publishing type：Research paper (scientific journal)
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Crystal Structures of Boc-D- and L-Iva-L-Pro-OBzl: Unturned Conformation of Aib-Pro Sequence Unaffected by Replacement of Me with Et inAib Reviewed
Masao KAWAI, Toshihisa OMORI, Hatsuo YAMAMURA, Yasuo BUTSUGAN, Tooru TAGA, Yoshihisa MIWA
Biopolymers 33 1207 - 1212 1993.04
Publishing type：Research paper (scientific journal)
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Determination of the Structures of Tris(6-O-mesitylenesulfonyl)-α-cyclodextrin Regioisomers by 1H NMR Analyses of the Corresponding 3,6-Anhydrocyclodextrin Derivatives Reviewed
Hatsuo Yamamura, Hideki Nagaoka, Kazuki Saito, Masao Kawai, Yasuo Butsugan, Terumi Nakajima, Kahee Fujita
Journal of Organic Chemistry 58 ( 11 ) 2936 - 2937 1993
Language：English Publishing type：Research paper (scientific journal)
The structures of two regioisomers of tris(6-O-mesitylenesulfonyl)-α-cyclodextrin (6A,6B,6D and 6A,6B,6E) were assigned by conversion of the isomers to tris(3,6-anhydro)-α-cyclodextrins and analyses of the two-dimensional 1H NMR spectra (DQF-COSY, HOHAHA, and ROESY) of the anhydrocyclodextrins. © 1993, American Chemical Society. All rights reserved.
DOI： 10.1021/jo00063a005
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Selective Preparation of Hexakis(6-O-arenesulfonyl)-alpha-cyclodextrin Reviewed
Kahee FUJITA, Kazuko OHTA, Kozo MASUNARI, Ken-ichi OBE, Hatsuo YAMAMURA
Tetrahedron Lett. 33 5519 - 5520 1992.04
Publishing type：Research paper (scientific journal)
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Physalins N and O from Physalis Alkekengi. Reviewed
Masao KAWAI, Toichi OGURA, Bunsho MAKINO, Akihide MATSUMOTO, Hatsuo YAMAMURA, Yasuo BUTSUGAN, Mitsuo HAYASHI
Phytochemistry 31 4299 - 4302 1992.04
Publishing type：Research paper (scientific journal)
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Optical Resolution of N-Carbobenzoxy-alpha-methoxyglycine. Reviewed
Masao KAWAI, Yoshimasa OMORI, Hatsuo YAMAMURA, Yasuo BUTSUGAN
Tetrahedron: Asymmetry 8 1019 - 1020 1992.04
Publishing type：Research paper (scientific journal)
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Bunsho MAKINO, Masao KAWAI, Tatsuo YAMAMOTO, Hatsuo YAMAMURA, Yasuo BUTSUGAN, Mitsuo HAYASHI, Kiyoshi OGAWA
J. Chem. Soc., Chem. Commun. 1430 - 1431 1992.04
Publishing type：Research paper (scientific journal)
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A Complete Set of 6A-Azido-6A-deoxy-6X-O-sulfonyl- beta-cyclodextrins. Reviewed
Kahee FUJITA, Hatsuo YAMAMURA, Yoshimitsu EGASHIRA, Taiji IMOTO
Tetrahedron Lett. 33 3511 - 3514 1992.04
Publishing type：Research paper (scientific journal)
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Activated charcoal-mediated hydroxylation under very mild conditions: Conversion of physalin B into 25-hydroxyphysalin B Reviewed
Bunsho Makino, Masao Kawai, Tatsuo Yamamoto, Hatsuo Yamamura, Yasuo Butsugan, Mitsuo Hayashi, Kiyoshi Ogawa
Journal of the Chemical Society, Chemical Communications ( 19 ) 1430 - 1431 1992
Language：English Publishing type：Research paper (scientific journal)
Activated charcoal treatment of physalin B, a 13, 14-seco-16,24- cyclosteroidal constituent of Physalis alkekengi, in MeOH at room temperature yields a product possessing a hydroxy group at the α-position of the δ-lactone carbonyl function, namely 25-hydroxyphysalin B, in high yield.
DOI： 10.1039/C39920001430
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Physalins N and O from Physalis alkekengi Reviewed
Masao Kawai, Toichi Ogura, Bunsho Makino, Akihide Matsumoto, Hatsuo Yamamura, Yasuo Butsugan, Mitsuo Hayashi
Phytochemistry 31 ( 12 ) 4299 - 4302 1992
Language：English Publishing type：Research paper (scientific journal)
The structures of physalins N and O, isolated from Physalis alkekengi var. francheti, were determined as 7α-hydroxyphysalin B and (25S)-25,27-dihydrophysalin A, respectively. © 1992.
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Optical resolution of N-carbobenzoxy-α-methoxyglycine Reviewed
Masao Kawai, Yoshimasa Omori, Hatsuo Yamamura, Yasuo Butsugan
Tetrahedron: Asymmetry 3 ( 8 ) 1019 - 1020 1992
Language：English Publishing type：Research paper (scientific journal)
Optical resolution of racemic N-carbobenzoxy-α-methxyglycine using D/L-phenylalaninol or (1S,2S)-2-amino-1-phenyl-1,3-propanediol afforded (+)- and (-)-enantiomers, to which D-and L-configurations, respectively, were assigned based on the 1H NMR data and biological activity of demorphin N-terminal tetrapeptide analogs. © 1992.
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A Complete Set of beta-Cyclodextrin 6A, 6X-Diactivated by Two Different Sulfonyl Groups Reviewed
Kahee FUJITA, Hatsuo YAMAMURA, Taiji IMOTO
Tetrahedron Lett. 32 6737 - 6740 1991.04
Publishing type：Research paper (scientific journal)
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Preparation of Heptakis(6-O-(p-tosyl))- beta-cyclodextrin and Heptakis(6-O-(p-tosyl))-2-O-(p-tosyl)- beta-cyclodextrin and TheirConversion to Heptakis(3,6-anhydro)- beta-cyclodextrin Reviewed
Hatsuo YAMAMURA, Kahee FUJITA
Chem. Pharm. Bull. 39 2505 - 2508 1991.04
Publishing type：Research paper (scientific journal)
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Preparation of Heptakis(6-0-(/?-tosyl))-/j-cyclodextrin And Heptakis(6-o-(/>-tosyl))-2-0-(/?-tosyl)-/j-cyclodextrin And Their Conversion To Heptakis(3,6-anhydro)-/j-cyclodextrin Reviewed
Hatsuo Yamamura, Kahee Fujita'
Chemical and Pharmaceutical Bulletin 39 ( 10 ) 2505 - 2508 1991
Language：English Publishing type：Research paper (scientific journal)
Heptakis(6-0-(/>
-tosyl))-/?-cyclodextrin and heptakis(6-0-(/Mosyl))-2-O-(/>
-tosyl)-/J-cyclodextrin were prepared by the reaction of /?-cyclodextrin with p-tosyl chloride in pyridine. They were converted to heptakis(3,6-anhydro)-/?-cyclodextrin, constituted from alternative (1C4) glucose units. © 1991, The Pharmaceutical Society of Japan. All rights reserved.DOI： 10.1248/cpb.39.2505
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Specific Preparation and Structure Determination of 3A,3C,3E-Tri-O-sulfonyl- beta-cyclodextrin. Reviewed
Kahee FUJITA, Tsutomu TAHARA, Hatsuo YAMAMURA, Taiji IMOTO, Toshitaka KOGA, Toshihiro FUJIOKA, Kunihide MIHASHI
J. Org. Chem. 55 877 - 8808 1990.04
Publishing type：Research paper (scientific journal)
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Specific Preparation and Structure Determination of 3A,3C,3E-Tri-O-sulfonyl-β-cyclodextrin Reviewed
Kahee Fuiita1, Tsutomu Tahara, Toshitaka Koga, Hatsuo Yamamura, Taiii Imoto, Toshihiro Fujioka, Kunihide Mihashi
Journal of Organic Chemistry 55 ( 3 ) 877 - 880 1990
Language：English Publishing type：Research paper (scientific journal)
A reaction of β-cyclodextrin with β-naphthylsulfonyl chloride in alkaline aqueous acetonitrile gave only one isomer (3A,3c,3E-trisulfonate, 17.8%) of five 3,3,3-tri-O-sulfonyl-β-cyclodextrins. The isomer was converted to 3Af6A:3c,6c:3E,6E-trianhydro-β-cyclodextrin, the structure of which was assigned by comparing its spectral and HPLC data of the trianhydro-β-cyclodextrin with those of all authentic 3,6:3,6:3,6-trianhydro-β-cyclodextrins prepared by the reactions of known 6-tri-O-sulfonylated β-cyclodextrins with aqueous alkali. © 1990, American Chemical Society. All rights reserved.
DOI： 10.1021/jo00290a016
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6-O-TRISUBSTITUTED BETA-CYCLODEXTRINS WHOSE SUBSTITUENTS ARE DIFFERENT FROM ONE ANOTHER Reviewed
K FUJITA, A MATSUNAGA, H YAMAMURA, T IMOTO
CHEMISTRY LETTERS ( 12 ) 1947 - 1950 1988.12
Language：English Publishing type：Research paper (scientific journal) Publisher：CHEMICAL SOC JAPAN
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Complete Sets of Structurally Determined 6A,6X-Unsymmetrically Disubstituted β-Cyclodextrins: 6A-S-Phenyl-6X-O-(β-Naphthylsulfonyl)-6A-Thio-β-Cyclodextrins and 6A-S-(tert-butyl)-6X-O-(β-Naphthylsulfonyl)-6A-thio-β-cyclodextrins Reviewed
Kahee Fujita, Atsuo Matsunaga, Hatsuo Yamamura, Taiji Imoto
Journal of Organic Chemistry 53 ( 19 ) 4520 - 4522 1988.09
Language：English Publishing type：Research paper (scientific journal)
Complete sets of structurally determined 6A,6X-unsymmetrically disubstituted β-cyclodextrins and 6A-S-phenyl-6X-O-(β-naphthylsulfonyl)-6A-thio-β-cyclodextrins and 6A-S-(tert-butyl)-6X-O-(β-naphthylsulfonyl)-6A-thio-β-cyclodextrins, were prepared, and their structures were determined. These constitute complete sets of cyclodextrins having two functional groups that are different from one another. © 1988, American Chemical Society. All rights reserved.
DOI： 10.1021/jo00254a019
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Synthesis of 6A,6X-Di-O-(p-tosyl)-gamma-cyclodextrins and Their Structural Determination through Enzymatic Hydrolysis of3A,6A;3X,6X-Dianhydro-gamma-cyclodextrins Reviewed
Kahee FUJITA, Hatsuo YAMAMURA, Taiji IMOTO, Toshiro FUJIOKA, Kunihide MIHASHI
J. Org. Chem. 53 1943 - 1947 1988.04
Publishing type：Research paper (scientific journal)
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Regiochemical Correlation between 6-O-Sulfonylated Cyclodextrins and 3-O-Sulfonylated Cyclodextrins via 3,6-Anhydrocyclodextrins. Reviewed
Kahee FUJITA, Tsutomu TAHARA, Yoshimitsu EGASHIRA, Hatsuo YAMAMURA, Taiji IMOTO, Toshitaka KOGA, Toshihiro FUJIOKA, Kunihide MIHASHI
Chem. Lett. ( 4 ) 705 - 708 1988.04
Language：English Publishing type：Research paper (scientific journal) Publisher：CHEMICAL SOC JAPAN
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Preparation of 3A,6A-Anhydro-beta-cyclodextrin and Its Taka Amylolysis Reviewed
Kahee FUJITA, Hatsuo YAMAMURA, Taiji IMOTO, Iwao TABUSHI
Chem. Lett. ( 3 ) 543 - 546 1988.04
Language：English Publishing type：Research paper (scientific journal) Publisher：The Chemical Society of Japan
3<SUP>A</SUP>,6<SUP>A</SUP>-Anhydro-β-cyclodextrin was prepared by the reaction of 6-<I>O</I>-(<I>p</I>-tosyl)-β-cyclodextrin with aqueous alkali. This anhydrocyclodextrin was enzymatically hydrolyzed by Taka amylase to give 3″,6″-anhydromaltotetraose exclusively.
DOI： 10.1246/cl.1988.543
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Complete Sets of Structurally Determined 6A,6X-Unsymmetrically Disubstituted beta-Cyclodextrins:6A-S-Phenyl-6X-O-(b-naphthylsulfonyl)-6A-thio-beta-cyclodextrins and 6A-S-(tert-Butyl)-6X-O-(b-naphthylsulfonyl)-6A-thio-beta-cyclodextrins Reviewed
Kahee FUJITA, Atsuo MATSUNAGA, Hatsuo YAMAMURA, Taiji IMOTO
J. Org. Chem. 53 4520 - 4522 1988.04
Publishing type：Research paper (scientific journal)
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6-O-Trisubstituted beta-Cyclodextrins Whose Substituents Are Different from One Another Reviewed
Kahee FUJITA, Atsuo MATSUNAGA, Hatsuo YAMAMURA, Taiji IMOTO
Chem. Lett. 1947 - 1950 1988.04
Publishing type：Research paper (scientific journal)
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SYNTHESIS OF 6A,6X-DI-OMICRON-(PARA-TOSYL)-GAMMA-CYCLODEXTRINS AND THEIR STRUCTURAL DETERMINATION THROUGH ENZYMATIC-HYDROLYSIS OF 3A,6A-PARA3X,6X-DIANHYDRO-GAMMA-CYCLODEXTRINS Reviewed
K FUJITA, H YAMAMURA, T IMOTO, T FUJIOKA, K MIHASHI
JOURNAL OF ORGANIC CHEMISTRY 53 ( 9 ) 1943 - 1947 1988.04
Language：English Publishing type：Research paper (scientific journal) Publisher：AMER CHEMICAL SOC
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Shigehiro KAMITORI, Ken HIROTSU, Taiichi HIGUCHI, Kahee FUJITA, Hatsuo YAMAMURA, Taiji IMOTO, Iwao TABUSHI
J. Chem. Soc. Perkin Trans. 1 7 - 14 1987.04
Publishing type：Research paper (scientific journal)
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6-Polysubstituted a-Cyclodextrins. Application of Korner's Absolute Method of Isomer Determination Reviewed
Kahee FUJITA, Hatsuo YAMAMURA, Atsuo YAMAMURA, Taiji IMOTO, Kunihide MIHASHI, Toshihiro FUJIOKA
J. Am. Chem. Soc. 108 4509 - 4513 1986.04
Publishing type：Research paper (scientific journal)
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Unsymmetrically Disubstituted beta-Cyclodextrins. 6A,6X-Dideoxy-6A-azido-6X [(mesitylsulfonyl)oxy] Derivatives. Reviewed
Kahee FUJITA, Hatsuo YAMAMURA, Taiji IMOTO
J. Org. Chem. 50 4393 - 4395 1985.04
Publishing type：Research paper (scientific journal)
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UNSYMMETRICALLY DISUBSTITUTED BETA-CYCLODEXTRINS - 6A,6X-DIDEOXY-6A-AZIDO-6X-[(MESITYLSULFONYL)OXY] DERIVATIVES Reviewed
K FUJITA, H YAMAMURA, T IMOTO
JOURNAL OF ORGANIC CHEMISTRY 50 ( 22 ) 4393 - 4395 1985
Language：English Publishing type：Research paper (scientific journal) Publisher：AMER CHEMICAL SOC
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