Special Issue

Masatomo Hamana's Special Issues, Vol. 33, No. 1, 1992

58 data found. 31 - 58 listedFirst Previous
Communication | Special issue | Vol 33, No. 1, 1992, pp. 157 - 160
Published online:
DOI: 10.3987/COM-91-S64
A Novel syntjesis of 4-Methyl-, 4-Oxo-, and 4-Amino-3-(3-methyl-5-isoxazolyl)pyridine Derivatives via N-Silyl-1-aza-allyl-Anion

Takeo Konakahara,* Naoki Sugama, and Kenji Sato

*Department of Industrial and Engineering Chemistry, Faculty of Science and Technology, Science University of Tokyo, 2641 Yamazaki, Noda, Chiba 278-8510, Japan

Abstract

An N -silyl-1-aza-ally1 anion (1) reacted with alkoxyalkenes (3a) - (3e) to afford the corresponding 4-methylpyridines (4a) and (4b), 4-pyridones (5c) and (5d), and 4-aminopyridine (4e) , possessing a 3-methyl-5-isoxazolyl group on C-3 atom, in 91, 90, 62, 27, and 68% yields, respectively, whereas alkoxyalkenes (3f ) and (3g) gave the corresponding N-adduct intermediates (6f ) and (6g) in 46 and 60% yields.

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Paper | Special issue | Vol 33, No. 1, 1992, pp. 161 - 171
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DOI: 10.3987/COM-91-S69
Synthetic Approaches to Phorbols via the Intramolevular Nitrile Oxide Cycloaddition: Stereocontrol of the B-C Ring Junction

Kazuhiko Shigeno, Kazuhiko Ohne, Tetsuo Yamaguchi, Hiroaki Sasai, and Masakatsu Sibasaki*

*Faculty of Pharmaceutical Sciences, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan

Abstract

The intramolecular cycloaddition of the nitrile oxide, synthesized from (+)-3-carene via 9 , provided the tetracyclic isoxazoline (10) stereospecifically. The isoxazoline (10) was converted to the carbotetracycle (17) via 15 utilizing the intramolecular McMurry coupling as a key step.

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Paper | Special issue | Vol 33, No. 1, 1992, pp. 173 - 177
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DOI: 10.3987/COM-91-S76
1-(2-Oxazolinyl)indoles

Yohko Takeda, Hironobu Nishiyama, Minoru Ishikawa, Kazuyuki Kamata, and Masanao Terashima*

*Faculty of Pharmaceutical Scicences, Higashinihonngakuen University, 1757 Kanazawa, Toubetu-cho, Ishikari-gun, Hokkaodo 061-0212, Japan

Abstract

Utilization of 1-(2-oxazolinyl)indoles, prepared from 1-cyano compounds, to the synthesis of 2-substituted indoles was investigated.

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Paper | Special issue | Vol 33, No. 1, 1992, pp. 179 - 188
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DOI: 10.3987/COM-91-S3
Reaction of Aromatic N-Oxides with Dipolarophiles. XVII. Cycloaddition Behavior of Allenes toward Pyridine N-Oxides and Formation of Azetidine-type Cycloadduct

Toshikazu Matsuoka, Tomoaki Hasegawa, Kazunobu Harao, and Takuzo Hisano*

*Faculty of Pharmaceutical Sciences, Kumamoto University, 5-1 Oe-hon-machi, Kumamoto 862-0973, Japan

Abstract

3,5-Dimethylpyridine N-oxide was allowed to react with phenylsulfonylpropadiene in CHCl3 at room temperature to give a mixture of the 1:1 [1,5] sigmatropic rearrangement product and the 1:2 azetidine-type cycloadduct. The structure of the azetidine-type cycloadduct was determined by single crystal X-ray analysis. The reaction behavior and the regioselectivity are discussed in terms of the frontier molecular orbital considerations.

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Paper | Special issue | Vol 33, No. 1, 1992, pp. 189 - 194
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DOI: 10.3987/COM-91-S5
Oxidation of Amines with 4a-FIEt-OOH: An Enzyme Model of FAD-Containing Monooxygenase

Shigeru Oae,* Kaoru Ogawa Asada, Toshiaki Yoshimura,and Ken Fujimori

*Department of Chemistry, University of Tsukuba, 1-1-1 Ten-nodai, Tsukuba-shi, Ibaraki, 305-8571, Japan

Abstract

Unlike the real enzyme, FAD-containing monooxygenase, 4a-FlEt-OOH, oxidizes most of common primary, secondary and tertiary water-soluble amines, such as N -methylmorpholine and n-octylamine. Both kinetic rates and products of the oxidation were obtained. The plots of the rates vs. pKa values gave three different correlations lines depending upon the types of amines.

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Paper | Special issue | Vol 33, No. 1, 1992, pp. 195 - 202
Published online:
DOI: 10.3987/COM-91-S7
A Synthesis of a New Type Heterocyclic Compound Using Deils-Alder Cycloaddition of 2-Methylene-1,2-dihydropyridines

Hiroto Nakano, Hiroshi Tomisawa, and Hiroshi Hongo*

*Tohoku Pharmaceutical University, 4-4-1 Komatsushima, Aoba-ku, Sendai 981-8558, Japan

Abstract

Diels-Alder cycloaddition of 2-methylene-1,2-dihydropyridines having an active methylene group at the 1-position with N-phenylmaleimide gave isoquinuclidines, and cyclization of the adducts obtained afforded a new type of heterocyclic ring system, 2-azatricyclo[5.2.2.02,6]undecanes.

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Paper | Special issue | Vol 33, No. 1, 1992, pp. 203 - 210
Published online:
DOI: 10.3987/COM-91-S11
Triazolopyridines. Part 12: A New Synthesis of Indolizines from Triazolopyridine Ylides

Belen Abarca, Rafael Ballesteros, Mohamed R. Metni, and Gurnos Jones*

*Department of Chemistry, University of Keele, Keele, staffordshire, ST5 5BG, U.K.

Abstract

Treatment of 2-acylmethyl-1,2,3-triazolo[1,5-a]pyridinium ylides (1) with methyl propiolate in non-polar solvent gives good yiedes of 1,2,3-trisubstituted indolizines (5). A mechanism for the transformation is suggested.

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Paper | Special issue | Vol 33, No. 1, 1992, pp. 211 - 218
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DOI: 10.3987/COM-91-S12
Preparation of Heteroarenecarbonitriles by Reaction of Heteroarene N-Oxides with Trimethylsilyl Cyanide in the Presence of DBU

Akira Miyashita,* Touru Kawashima, Chihoko Iijima, and Takeo Higashino

*Schol of Pharmaceutical Sciences, University of Shizuoka, 52-1 Yada, Shizuoka 422-8526, Japan

Abstract

Several heteroarenecarbonitriles were prepared from the corresponding heteroarene N-oxides by treatment with trimethylsilyl cyanide (TMSCN) in the presence of a base in tetrahydrofuran (THF). 1,8-Diazabicyclo[5.4.0]-7-undecene (DBU) was found to be an effective base for the cyanation.

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Paper | Special issue | Vol 33, No. 1, 1992, pp. 219 - 228
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DOI: 10.3987/COM-91-S13
A Synthetic Approache to (±)-O-Methylclavizepine: An Alternative Synthesis of C-Norcularine

Hiroshi Hara, Masanori Kishigami, Masaki Endoh, Ken-ichi Kaneko, and Osamu Hoshino*

*Faculty of Pharmaceutical Sciences, Science University of Tokyo, 12, Ichigaya Funagawara-machi, Shinjuku-ku, Tokyo 162-0826, Japan

Abstract

C-Norcularine (2) was synthesized stepwise via the xanthone (3) or by intramolecular Pictet-Spengler reaction directly from the amino aldehyde (10).

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Paper | Special issue | Vol 33, No. 1, 1992, pp. 229 - 233
Published online:
DOI: 10.3987/COM-91-S21
Two Complex Flavonoids in the Farinose Exudate of Pityrogramma calomelanos

Fujio Asai, Munekazu Iinuma,* Toshiyuki Tanaka, and Mizuo Mizuno

*Department of Pharmacognosy, Gifu Pharmaceutical University, 6-1 Mitahora-higashi 5-chome, Gifu 502-8585, Japan

Abstract

From the farinose exudate of Pityrogramma calomelanos, two new complex flavonoids named calomelanols D and E were isolated. Their structures were determined by spectroscopic analysis.

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Paper | Special issue | Vol 33, No. 1, 1992, pp. 235 - 255
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DOI: 10.3987/COM-91-S23
Synthesis of 2-Indolyl-1,4-benzodiazepin-5-ones Utilizing a mannich Type Cyclization

Nobuyuki Matsunaga, Hiroshi Harada, Toyohiko Aoyama, and Takayuki Shioiri*

*Faculty of Pharmaceutical Sciences, Nagoya City University, Tanabe-dori, Mizuho-ku, Nagoya 467-8603, Japan

Abstract

2-Indolyl-1,4-benzodiazepin-5-ones (3) have been efficiently synthesized from Boc-α-amino acids (4), 3-hydroxyanthranilic acid (8), and indole; the key step is a Mannich type cyclization accompanied with introduction of indole.

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Paper | Special issue | Vol 33, No. 1, 1992, pp. 257 - 272
Published online:
DOI: 10.3987/COM-91-S29
Palladium-catalyzed Cross-coupling Ractions of Chloropyrazines with Aromatic Heterocycles

Yutaka Aoyagi, Akira Inoue, Isamu Koizumi, Rie Hashimoto, Kazuko Tokunaga, Kaori Gohma, Junko Komatsu, Kumiko Sekine, Ayako Miyafuji, Jun Kunoh, Rieko Honma, (the late) Yasuo Akita, and Akihiro Ohta*

*Tokyo College of Pharmacy, 1432-1 Horinouchi, Hachioji, Tokyo 192-0392, Japan

Abstract

In the presence of tetrakis(triphenylphosphine)palladium, chloropyrazines were treated with aromatic heterocycles such as furan, thiophene, pyrrole, N-substituted pyrroles, benzo[b]furan, benzo[b]thiophene, oxazole, thiazole, N-methylimidazoles, benz[b]oxazole and benzo[b]thiazole. The corresponding coupling products were obtained in moderate to good yields. The structures of the coupling products were determined.

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Paper | Special issue | Vol 33, No. 1, 1992, pp. 273 - 279
Published online:
DOI: 10.3987/COM-91-S31
Formation of 2,5-Dihydro-3H-pyrazolo[4,3-c]quinolin-3-ones from Ethyl 3-Amilino-2-(2-tert-butyl-2H-tetrazol-5-yl)acrylates

Sumiro Isoda* and Hideyuki Kanno

*Tokyo R&D Center, Daiichi Pharmaceutical Co., Ltd., 16-13, Kitakasai 1-chome, Edsogawa-ku, Tokyo 134, Japan

Abstract

Thermal cyclization of ethyl 2-(2-tert -butyl-2H-tetrazol-5-yl)-3-(4-chloroanilino)acrylate (5) did not afford the intended 4-quinolinone derivative (6) , but yielded 2,5-dihydro-3H-pyrazolo[4,3-c]quinolin-3-one (7) . The reaction mechanism is thought to have been double cyclization of the nitrile imine intermediate (C).

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Paper | Special issue | Vol 33, No. 1, 1992, pp. 281 - 290
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DOI: 10.3987/COM-91-S32
Syntheses and Absolute Configurations of Optically Pure 4-Isopropyl-N-tosyl-1,3-oxazolidines

Hiroshi Takahashi,* Takeshi Tubuki, and Kimio Higashiyama

*Faculty of Pharmaceutical Sciences, Hoshi University, 2-4-41 Ebara, Shinagawa-ku, Tokyo 142-8501, Japan

Abstract

(2S,4S)-4-Isopropyl-N-tosyl-1,3-oxazolidines (3a-e)having methyl, cyclohexyl, phenyl, o-bromophenyl, or o-formylphenyl group at the 2-position of the ring were synthesized, and these products were confirmed to consist of one isomer by 1H-nmr spectral analyses in spite of a newly created asymmetric center at the 2-position. The absolute configurations of 3a-e were determined by difference nuclear Overhauser effect studies.

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Paper | Special issue | Vol 33, No. 1, 1992, pp. 291 - 294
Published online:
DOI: 10.3987/COM-91-S34
Synthesis of a Naturally Occurring Benzocyclobutene, Muscomosin

Toshio Honda* and Tetsuya Toya

*Institute of Medicinal Chemistry, Hoshi University, 2-4-41 Ebara, Shinagawa-ku, Tokyo 142-8501, Japan

Abstract

A naturally occuning benzocyclobutene, muscomosin (2) was synthesized from 1-cyanobenzocyclobutene derivative.

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Paper | Special issue | Vol 33, No. 1, 1992, pp. 295 - 302
Published online:
DOI: 10.3987/COM-91-S35
Thermal Reaction of Benzimidazolium N-Allylides

Yoshiro Matsuda,* Makoto Yamashita, Kimitoshi Takahashi, Shizuki Ide, Katsura Torisu, and Kazuki Furuno

*Faculty of Pharmaceutical Sciences, Nagasaki University, 1-14, Bunkyo-machi, Nagasaki 852-8521, Japan

Abstract

The reaction of benzimidazolium salt (3) and polarized olefins (1a,b,d and 2c) with K2CO3 in CHCl3 gave the corresponding benzimidazolium N -allylides (4a-d). Thermolyses of N-allylides (4a,b) in refluxing xylene afforded the 1,5-dipolar
cyclization product, benzopyrroloimidazole (5a), whereas heating of N-allylides (4c,d) resulted in back-donated 1,6-cyclization to give the mesomeric betaines, benzimidazopyridiniumides (7a,b). Treatment of 3 and 2a with K2CO3 in CHCl3 yielded directly benzopyrroloimidazole (5b), while similar treatment of 3 with
1c or 2b gave benzopyrrolopyrazines (6a,b).

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Paper | Special issue | Vol 33, No. 1, 1992, pp. 303 - 311
Published online:
DOI: 10.3987/COM-91-S36
Synthesis and Neuroexcitatory Activity of Some Acromelic Acid Analogs

Katsuhiro Konno, Kimiko Hashimoto, and Haruhisa Shirahama*

*Department of Chemistry, Faculty of Science, Hokkaido University, Sapporo 060-0810, Japan

Abstract

The pyridine derivatives (6~9), analogs of acromelic acid A (1) which were potent excitatory amino acids, were synthesized. In the crayfish neuromuscular junction, depolarizing activity of these derivatives was comparable to those of acromelic acid A and domoic acid. At the isolated rat spinal motoneurons, compounds (6), (7) and (8) were found to be powerful excitants as potent as kainic acid, while 9 was inactive.

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Paper | Special issue | Vol 33, No. 1, 1992, pp. 313 - 326
Published online:
DOI: 10.3987/COM-91-S40
Synthesis and Biological Evalution of Functionalized Epoxides Structurally Related to the Carbapenem Family

Jacqueline Marchand-Brynaert, John Davies, and Léon Ghosez*

*Laboratoire de Chimie Organique de Synthèse, Université Catholique de Louvain, Place Louis Pasteur 1, B-1348 Louvain-la-Neuve, Belgium

Abstract

Epoxides (6) and (7), topologically related to the carbapenem antibiotics,
were designed as potential alkylating inhibitors of the bacterial D,D-peptidases. The
olefinic precursors (8-9) were readily prepared, in three steps, by coupling the Wittig
reagent (13) with the aldehyde synthons (10) or (11) resulting from diastereoselective aldol condensations. Epoxide (7) showed a weak anti-β-lactamase activity.

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Paper | Special issue | Vol 33, No. 1, 1992, pp. 327 - 336
Published online:
DOI: 10.3987/COM-91-S43
Elucidation of the Reaction Path for the Nitrosation of 2- and 4-Methylpyridine 1-Oxides with Alkyl Nitrite in Liquid Ammonia

Yoshinobu Tagawa, Hideo Togashi, and Yoshinobu Goto*

*Faculty of Pharmaceutical Sciences, Fukuoka University, Nakamura, Jonan-ku, Fukuoka, 814-0180, Japan

Abstract

The reaction path for the nitrosation of 2- and 4-methylpyridine 1-oxides with alkyl nitrite in the presence of NaNH2 in liquid NH3 was elucidated experimentally, and theoretically by the use of a semiempirical molecular orbital method (PM3 method). In the case of the nitrosation of 4-methylpyridine 1-oxide at room temperature, only 4-pyridinecarboxamide 1-oxide was obtained, while at -33°C a thermodynamically unstable aldoxime, (Z )-4-pyridinecarbaldehyde 1-oxide oxime, which was easily transformed into E-form by heating, was obtained. On the other hand, the nitrosation of 2-methylpyridine 1-oxide gave only a thermodynamically stable aldoxime, (E)-2-pyridinecarbaldehyde 1-oxide oxime, both at room temperature and at -33°C. These results were reasonably explained by PM3 method.

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Paper | Special issue | Vol 33, No. 1, 1992, pp. 337 - 348
Published online:
DOI: 10.3987/COM-91-S44
Tetracyanoquinodimethanes Fused with 1,2,5-Thiadiazole and Pyrazine Units

Yoshiaki Tsubota, Takanori Suzuki, Yoshiro Yamashita, Toshio Mukai, and Tsutomu Miyashi*

*Department of Chemistry, Faculty of Science, Tohoku University

Abstract

1,2,5-Thiadiazolopyrazino-TCNQs underwent reversible four-stage one-electron reduction and gave conductive CT complexes with some donors. The X-ray structural analysis of the unsubstituted derivative revealed that the coplanar “sheet”- like network was formed by interatomic contacts of S--N≡C and H--N≡C in crystal.

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Paper | Special issue | Vol 33, No. 1, 1992, pp. 349 - 356
Published online:
DOI: 10.3987/COM-91-S45
Synthesis of (±)-Tetrahydropseudodistomin, a Hydrogenation Product of Antineoplastic Alkaloids, Pseudodistomins A and B

Iwao Utsunomiya, Masashi Ogawa, and Mitsutaka Natsume*

*Research Foundation Itsuu Laboratory, 2-28-10 Tamagawa, Setagaya-ku, Tokyo 158, Japan

Abstract

2-Alkyl-1,2,3,6-tetrahydro-3-pyridinols (6, R2 = H) with trans arrangement of the side chains were prepared by sodium cyanoborohydride reduction of the singlet oxygen adducts (5) of 1,2-dihydropyridine derivatives (4) in the presence of tin (II) chloride. Stereoselective synthesis of (±)-tetrahydropseudodistomin (3) was achieved starting from one of such reaction products (10) by way of 12 and 14.

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Paper | Special issue | Vol 33, No. 1, 1992, pp. 357 - 374
Published online:
DOI: 10.3987/COM-91-S47
Synthesis of (+)- and (-)-Mellein Utilkizing an Annelation Reaction of Isoxazoles with Dimethyl 3-Oxoglutarate

Naoki Takeuchi,* Kaori Goto, Yuki sasaki, Takashi Fujita, Kohsuke Okazaki, Kohji Kamata, and Seisho Tobinaga

*Showa College of Pharmaceutical Sciences, 3-3165, Higashi-tamagawagakuen, Machida, Tokyo 194-8543, Japan

Abstract

Naturally occurring dihydroisocoumarins, (+) - and (-) -mellein (2 and 3), metabolites of fungals, Cercospora sp. and Aspergillus sp., etc., were synthesized from the isoxazoles (32) and (33) by the annelation reactions with dimethyl 3-oxoglutarate.

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Paper | Special issue | Vol 33, No. 1, 1992, pp. 375 - 383
Published online:
DOI: 10.3987/COM-91-S50
Reaction of Dehydroellagitannins with L-Cysteine Methyl Ester

Takashi Tanaka, Hiroshi Fujisaki, Gen-ichiro Nonaka,* and Itsuo Nishioka

*Faculty of Pharmaceutical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan

Abstract

Reaction of dehydroellagitannins (e.g . 1 ) with L-cysteine methyl ester (5) at room temperature yielded the condensation products (e.g. 3 and 4), together with a partial hydrolysate (e.g. 2), while heating the mixture at 80ÅãC afforded 4 and the hydrolysate(2) in fairly good yields. In addition, reduction of a dehydrohexahydroxydiphenoyl ester group to a hexahydroxy-diphenoyl group with thiols is also described.

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Paper | Special issue | Vol 33, No. 1, 1992, pp. 385 - 390
Published online:
DOI: 10.3987/COM-91-S67
Ozonolysis of 1-Substituted Imidazoles

Choji Kashima,* Kaori Harada, and Akira Hosomi

*Department of Chemistry, University of Tsukuba, 1-1-1 Ten-nodai, Tsukuba-shi, Ibaraki, 305-8571, Japan

Abstract

1-Substituted imidazoles was ozonolyzed cleanly without any complicated procedures into the corresponding N-acylamides, which were regarded to be much useful derivatives of either amines or acyl compounds.

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Paper | Special issue | Vol 33, No. 1, 1992, pp. 391 - 404
Published online:
DOI: 10.3987/COM-91-S78
A Synthesis and an X-Ray Analysis of 2'-C-, 3'-C- and 5'-C-Methylsangivamycins

Yasushi Murai, Hironori Shiroto, Tatsuya Ishizaki. Takamasa Iimori,* Yoshio Kodama, Yasuo Ohtsuka, and Takeshi Oishi

*Faculty of Engineering, Yokohama National University, Tokiwadai, Hodogaya-ku, Yokohama 240-8501, Japan

Abstract

3’-C, 5’(R)-C - and 5’(S)-C-Methylsangivamycins (3-5) were synthesized by
the trimethylsilyl triflate mediated coupling reaction of the methyl substituted ribose
derivatives (7), (9) and (1 0) with me base moiety (1 1) and the successive functional
group manipulation. 2’-C -Methylsangivamycin (2) was synthesized by the condensation of the sodium salt of 23 with the chlorosugar (28) as me key step. The crystalline structures of C -methyisangivamycins (2-4) were determined by X-ray studies.

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Review | Special issue | Vol 33, No. 1, 1992, pp. 405 - 434
Published online:
DOI: 10.3987/REV-91-SR4
Mass Spectrometry of Prenylated Flavonoids

Mitsuo Takayama, Toshio Fukai, Yoshio Hano, and Taro Nomura*

*Faculty of Pharmaceutical Sciences, Toho University, 2-2-1, Miyama, Funabashi, Chiba 274-8510, Japan

Abstract

The fragmentation patterns originating from the degradation of prenyl group(s) in positive ion electron ionization (EI), fast-atom bombardment (FAB) and chemical ionization (CI) mass spectrometry (MS) of prenylated flavonoids were reviewed. The EI spectra showed the characteristic fragmentation patterns reflecting the location of prenyl group in the flavonoid compounds, whereas the FAB and CI spectra showed relatively monotonous patterns. It was described how the El and FAB fragmentation patterns are useful for the identification of prenylated flavonoids.

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Review | Special issue | Vol 33, No. 1, 1992, pp. 435 - 462
Published online:
DOI: 10.3987/REV-91-SR6
Development of Modified Chiral Dioxolane Bisphosphine Ligands and Their Use in Efficient Asymmetric Synthesis of Naturally Occurring Lignans

Toshiaki Morimoto, Mitsuo Chiba, and Kazuo Achiwa*

*Schol of Pharmaceutical Sciences, University of Shizuoka, 52-1 Yada, Shizuoka 422-8526, Japan

Abstract

This review deals with our recent works on the development of efficient chiral bisphisphine ligands, modified DIOPs, bearing a dioxolane framework and their application to the asymmetric total synthesis of naturally occurring lignans such as (+)-collinusin, (-)-deoxypodophyllotoxin, and (+)-neoisostegane using rhodium(I)-catalyzed asymmetric hydrogenation of itaconic acid derivatives as a key step. Related asymmetric total syntheses of lignans using an equimolar amount of chiral sources are also reviewed.

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Review | Special issue | Vol 33, No. 1, 1992, pp. 463 - 482
Published online:
DOI: 10.3987/REV-91-SR7
Oligomeric Hydrolyzable Tannins — Their 1H NMR Spectra and Partial Degradation

Takashi Yoshida, Tsutomu Hatano, Takako Kuwajima, and Takuo Okuda*

*Faculty of Pharmaceutical Sciences, Okayama University, 1-1-1 Tsushima-naka, Okayama 700-8530, Japan

Abstract

The 1H nmr spectroscopy provides a convenient method of assigning the orientation of the valoneoyl group in the oligomeric hydrolyzable tannins, which is the unit most frequently joining the monomeric constituents in the molecules. The behavior of oligomers upon partial degradation has been found to be dependent on the location of valoneoyl group on the glucose core.

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58 data found. 31 - 58 listedFirst Previous