Studies of the Selective O-Alkylation and Dealkylation of Flavonoids. XX. A Convenient Method for Synthesizing 5,6,7-Trihydroxyisoflavones and 5,6-Dihydroxy-7-methoxyisoflavones
スポンサーリンク
概要
- 論文の詳細を見る
3', 6'-Bis(benzyloxy)-2', 4'-dimethoxychalcones, which were derived from dibenzyl ether of 3,6-dihydroxy-2,4-dimethoxyacetophenone, were oxidatively rearranged with thallium(III) nitrate (TTN) in methanol to give 2-aryl-1-[3,6-bis(benzyloxy)-2,4-dimethoxyphenyl]-3,3-dimethoxypropan-1-ones; these products were converted into 6-hydroxy-5,7-dimethoxyisoflavones by hydrogenolysis followed by cyclization. The 5-methoxy group in the acetates of the isoflavones was selectively cleaved with 5% (w/v) anhydrous aluminum bromide in acetonitrile to give quantitatively the corresponding 5-hydroxyisoflavones, which were hydrolyzed to 5,6-dihydroxy-7-methoxy-isoflavones. The acetates were also demethylated to 5,6,7-trihydroxyisoflavones with 30% (w/v) anhydrous aluminum chloride in acetonitrile at 70℃ for 36-48 h. The spectral properties of these isoflanones were examined and some natural isoflavones were identified.
- 公益社団法人日本薬学会の論文
- 1996-03-15
著者
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Yamashita Kazumi
Faculty Of Pharmaceutical Sciences Okayama University
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KAWAMURA Yasuhiko
Department of Chemical Science and Technology, Faculty of Engineering, The University of Tokushima
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YAMASHITA Kazuyo
Department of Chemical Science and Technology, Faculty of Engineering, The University of Tokushima
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Yamashita K
Department Of Chemical Science And Technology Faculty Of Engineering The University Of Tokushima
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Horie Tokunaru
Department of Applied Chemistry, Faculty of Engineering, Tokushima University
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HORIE Tokunaru
Midori Kagaku Co., Ltd.,
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SASAGAWA Masahiro
Department of Chemical Science and Technology, Faculty of Engineering, The University of Tokushima
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TORII Fumihito
Department of Chemical Science and Technology, Faculty of Engineering, The University of Tokushima
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Horie T
Midori Kagaku Co. Ltd.
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Torii Fumihito
Department Of Chemical Science And Technology Faculty Of Engineering The University Of Tokushima
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Sasagawa Masahiro
Department Of Chemical Science And Technology Faculty Of Engineering The University Of Tokushima
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Kawamura Y
Department Of Chemical Science And Technology Faculty Of Engineering The University Of Tokushima
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Kawamura Yasuhiko
Department Of Chemical Science And Technology Faculty Of Engineering The University Of Tokushima
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Sasagawa Masahiro
Department of Applied Chemistry, Faculty of Science and Technology, Keio University
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Kawamura Yasuhiko
Department of Applied Chemistry, Faculty of Engineering, Tokushima University
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