著者

岩田 顕 井貫 晋輔 大石 真也 藤井 信孝 大野 浩章

出版者

日本薬学会化学系薬学部会

雑誌

反応と合成の進歩シンポジウム 発表要旨概要

巻号頁・発行日

vol.37, pp.164, 2011

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The family of ergot alkaloids produced by the fungus <I>Claviceps purpurea</I> is one of the most intriguing classes of natural products because of their broad biological and pharmacological activities. Despite intensive synthetic investigations, most synthetic studies of the ergot alkaloids, particularly (+)-lysergic acid, (+)-lysergol and (+)-isolysergol, have relied on a stepwise linear approach for the construction of the C/D ring system. Recently, we developed a palladium-catalyzed domino cyclization of the racemic allenic amide to provide the tetracyclic core of ergot alkaloids. In this study, we constructed the chiral allenic amide via the two synthetic routes using aldehyde alkynylation/asymmetric hydrogenation or asymmetric epoxidation/regioselective reductive ring-opening reaction. Using the resulting chiral allenic amide , enantioselective total syntheses of (+)-lysergic acid, (+)-lysergol and (+)-isolysergol were accomplished.