著者

木梨 陽康 染野 衣美 坂口 健二 東島 勉 宮沢 辰雄

出版者

天然有機化合物討論会実行委員会

雑誌

天然有機化合物討論会講演要旨集

巻号頁・発行日

vol.24, pp.183-190, 1981

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Concanamycins A (1a), B (1b), and C (1c) were found as inhibitors of the proliferation of the mouse splenic lymphocytes stimulated by concanavalin A. For the structure determination of the main component, concanamycin A (1a), several chemical transformations were performed. Treatment of (1a) with 0.03N NaOH in methanol afforded an anhydroagly-cone P1 (2a) and a sugar S1 (3a), and their structures were determined by 270MHz PMR analysis. In order to elucidate the mode of binding of these components, ozonolysis of (1a) was performed. Of the three degradation products, Oz3 (5) proved to be the key compound containing S1 and a fragment of P1. Extensive PMR analysis of (5) and (1a) itself revealed the full structure of (1a). Thus, concanamycin A (1a) is a novel 18-membered macrolide antibiotic consisting of an α,β,γ,δ-unsaturated lactone ring, a long side chain which forms an intramolecular hemiketal ring, and 4-O-carbamyl-2-deoxy-D-rhamnose. The structures of concanamycin B (1b) and C (1c) were also determined by chemical trans-formations and spectroscopic methods.