著者

原 修 中尾 一成 棚田 喜久 西尾 東 松原 淳 横川 文明 濱田 康正 塩入 孝之

出版者

天然有機化合物討論会

雑誌

天然有機化合物討論会講演要旨集

巻号頁・発行日

no.32, pp.617-624, 1990-09-25

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Calyculins having high cytotoxicity were isolated from the marine sponge Discordermia calyx in the Gulf of Sagami. Calyculin A (1), the major cytotoxic constituent, has 15 chiral centers, a spiroketal bearing phosphate, an oxazole ring, and a nitrile conjugated with all (E)-tetraene. However, its absolute stereostructure has remained uncovered. Interestingly, calyculin A (1) exhibits antitumor activity against Ehrlich and P-388 leukemia in mice. Its unique complex structure as well as its intriguing biological activity led us to investigate the total synthesis of 1, which will determine the absolute configuration of 1 as well. Retrosynthetic analysis has revealed that 1 would be constructed from four fragments A, B, C, and D, shown in Chart 1. Fragments A and B could be prepared by stereoselective reduction of tetronic acid derivatives 11 and 24, respectively. Fragments C and D were prepared from amino acids utilizing the methodology developed by us earlier.

著者

横川 文明 塩入 孝之

出版者

The Society of Synthetic Organic Chemistry, Japan

雑誌

有機合成化学協会誌 (ISSN:00379980)

巻号頁・発行日

vol.58, no.7, pp.634-641, 2000-07-01

被引用文献数

4

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Antillatoxin is an ichthyotoxic cyclic lipopeptide isolated by Gerwick and co-workers from the marine cyanobacterium <I>Lyngbya majuscula</I> collected in Curacao. Although we have finished the stereoselective total synthesis of antillatoxin having the proposed structure with (4<I>S</I>, 5<I>R</I>) -configuration, we have found that the synthetic sample was not identical with the natural one and the proposed structure should be revised. Further our synthetic efforts have culminated in the first total synthesis of antillatoxin in its natural form, proving that the natural one has (4<I>R</I>, 5<I>R</I>) -configuration. In this account, our total synthesis and synthetic studies by other groups will be discussed.

著者

横川 文明 塩入 孝之

出版者

社団法人 有機合成化学協会

雑誌

有機合成化学協会誌 (ISSN:00379980)

巻号頁・発行日

vol.58, no.7, pp.634-641, 2000-07-01 (Released:2009-11-13)

参考文献数

29

被引用文献数

2 4

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Antillatoxin is an ichthyotoxic cyclic lipopeptide isolated by Gerwick and co-workers from the marine cyanobacterium Lyngbya majuscula collected in Curacao. Although we have finished the stereoselective total synthesis of antillatoxin having the proposed structure with (4S, 5R) -configuration, we have found that the synthetic sample was not identical with the natural one and the proposed structure should be revised. Further our synthetic efforts have culminated in the first total synthesis of antillatoxin in its natural form, proving that the natural one has (4R, 5R) -configuration. In this account, our total synthesis and synthetic studies by other groups will be discussed.