Total Synthesis of Lyconesidine B, a Lycopodium Alkaloid with an Oxygenated, Amine-Type Fawcettimine Core.


Kurose T(1), Tsukano C(2), Nanjo T(1), Takemoto Y(1).
Author information:
(1)Graduate School of Pharmaceutical Sciences, Kyoto University, Yoshida, Sakyo-ku, Kyoto 606-8501, Japan.
(2)Graduate School of Agriculture, Kyoto University, Kitashirakawa oiwake-cho, Sakyo-ku, Kyoto 606-8502, Japan.


This report describes the total synthesis of the complex, oxygenated tetracyclic alkaloid, lyconesidine B. The key synthetic challenge involves diastereoselective generation of a decahydroquinoline ring with a quaternary carbon at the angular position via domino cyclopropanation, ring-opening, and reduction. Another crucial step is the domino ene-yne metathesis involving a quaternary ammonium ion, leading to the construction of a decahydroazaazulen framework.