論文 - 山村 初雄
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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 査読あり
M KAWAI, Y OMORI, H YAMAMURA, Y BUTSUGAN, T TAGA, Y MIWA
BIOPOLYMERS 33 ( 8 ) 1207 - 1212 1993年08月
記述言語:英語 掲載種別:研究論文(学術雑誌) 出版者・発行元: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. 査読あり
Hatsuo YAMAMURA, Yoshitaka KAWASE, Masao KAWAI, Yasuo BUTSUGAN
Bull. Chem. Soc. Jpn. 66 ( 2 ) 585 - 588 1993年04月
記述言語:英語 掲載種別:研究論文(学術雑誌) 出版者・発行元: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年04月
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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. 査読あり
Hatsuo YAMAMURA, Hideki NAGAOKA, Kazuki SAITO, Masao KAWAI, Yasuo BUTSUGAN
J. Org. Chem. 58 2936 - 2937 1993年04月
掲載種別:研究論文(学術雑誌)
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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 査読あり
Masao KAWAI, Toshihisa OMORI, Hatsuo YAMAMURA, Yasuo BUTSUGAN, Tooru TAGA, Yoshihisa MIWA
Biopolymers 33 1207 - 1212 1993年04月
掲載種別:研究論文(学術雑誌)
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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 査読あり
Hatsuo Yamamura, Hideki Nagaoka, Kazuki Saito, Masao Kawai, Yasuo Butsugan, Terumi Nakajima, Kahee Fujita
Journal of Organic Chemistry 58 ( 11 ) 2936 - 2937 1993年
記述言語:英語 掲載種別:研究論文(学術雑誌)
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 査読あり
Kahee FUJITA, Kazuko OHTA, Kozo MASUNARI, Ken-ichi OBE, Hatsuo YAMAMURA
Tetrahedron Lett. 33 5519 - 5520 1992年04月
掲載種別:研究論文(学術雑誌)
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Physalins N and O from Physalis Alkekengi. 査読あり
Masao KAWAI, Toichi OGURA, Bunsho MAKINO, Akihide MATSUMOTO, Hatsuo YAMAMURA, Yasuo BUTSUGAN, Mitsuo HAYASHI
Phytochemistry 31 4299 - 4302 1992年04月
掲載種別:研究論文(学術雑誌)
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Optical Resolution of N-Carbobenzoxy-alpha-methoxyglycine. 査読あり
Masao KAWAI, Yoshimasa OMORI, Hatsuo YAMAMURA, Yasuo BUTSUGAN
Tetrahedron: Asymmetry 8 1019 - 1020 1992年04月
掲載種別:研究論文(学術雑誌)
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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年04月
掲載種別:研究論文(学術雑誌)
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A Complete Set of 6A-Azido-6A-deoxy-6X-O-sulfonyl- beta-cyclodextrins. 査読あり
Kahee FUJITA, Hatsuo YAMAMURA, Yoshimitsu EGASHIRA, Taiji IMOTO
Tetrahedron Lett. 33 3511 - 3514 1992年04月
掲載種別:研究論文(学術雑誌)
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Activated charcoal-mediated hydroxylation under very mild conditions: Conversion of physalin B into 25-hydroxyphysalin B 査読あり
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年
記述言語:英語 掲載種別:研究論文(学術雑誌)
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 査読あり
Masao Kawai, Toichi Ogura, Bunsho Makino, Akihide Matsumoto, Hatsuo Yamamura, Yasuo Butsugan, Mitsuo Hayashi
Phytochemistry 31 ( 12 ) 4299 - 4302 1992年
記述言語:英語 掲載種別:研究論文(学術雑誌)
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 査読あり
Masao Kawai, Yoshimasa Omori, Hatsuo Yamamura, Yasuo Butsugan
Tetrahedron: Asymmetry 3 ( 8 ) 1019 - 1020 1992年
記述言語:英語 掲載種別:研究論文(学術雑誌)
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 査読あり
Kahee FUJITA, Hatsuo YAMAMURA, Taiji IMOTO
Tetrahedron Lett. 32 6737 - 6740 1991年04月
掲載種別:研究論文(学術雑誌)
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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 査読あり
Hatsuo YAMAMURA, Kahee FUJITA
Chem. Pharm. Bull. 39 2505 - 2508 1991年04月
掲載種別:研究論文(学術雑誌)
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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 査読あり
Hatsuo Yamamura, Kahee Fujita'
Chemical and Pharmaceutical Bulletin 39 ( 10 ) 2505 - 2508 1991年
記述言語:英語 掲載種別:研究論文(学術雑誌)
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. 査読あり
Kahee FUJITA, Tsutomu TAHARA, Hatsuo YAMAMURA, Taiji IMOTO, Toshitaka KOGA, Toshihiro FUJIOKA, Kunihide MIHASHI
J. Org. Chem. 55 877 - 8808 1990年04月
掲載種別:研究論文(学術雑誌)
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Specific Preparation and Structure Determination of 3A,3C,3E-Tri-O-sulfonyl-β-cyclodextrin 査読あり
Kahee Fuiita1, Tsutomu Tahara, Toshitaka Koga, Hatsuo Yamamura, Taiii Imoto, Toshihiro Fujioka, Kunihide Mihashi
Journal of Organic Chemistry 55 ( 3 ) 877 - 880 1990年
記述言語:英語 掲載種別:研究論文(学術雑誌)
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 査読あり
K FUJITA, A MATSUNAGA, H YAMAMURA, T IMOTO
CHEMISTRY LETTERS ( 12 ) 1947 - 1950 1988年12月