Papers - YAMAMURA Hatsuo
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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)
