Total Synthesis of (−)‐Isoschizogamine |
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| Authors: | Dr Akihiro Takada Hiroaki Fujiwara Dr Kenji Sugimoto Dr Hirofumi Ueda Prof?Dr Hidetoshi Tokuyama |
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| Affiliation: | Graduate School of Pharmaceutical Sciences, Tohoku University, Aoba 6‐3, Aramaki, Aoba‐ku, Sendai 980‐8578 (Japan), Fax: (+81)?22‐795‐6877 |
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| Abstract: | The total synthesis of (?)‐isoschizogamine was accomplished, featuring the construction of the quaternary carbon center by the modified Johnson–Claisen rearrangement in basic media and the facile assembly of the key tetracyclic quinolone intermediate through a cascade cyclization. The characteristic cyclic aminal was constructed by late‐stage C?H functionalization at the position adjacent to the lactam nitrogen using a combination of CrO3 and nBu4NIO4 and subsequent Bi(OTf)3‐mediated cyclization. |
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| Keywords: | alkaloids aminal cascade reaction C H functionalization total synthesis |
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