Papers - YAMAMURA Hatsuo
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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.
