Lycojaponicumins D and E: Two New Alkaloids from <i>Lycopodium japonicum</i>

Abstract

Two new alkaloids, lycojaponicumins D (<b>1</b>) and E (<b>2</b>), were isolated from the club moss <i>Lycopodium japonicum</i>. Their structures were elucidated by spectroscopic methods, calculated ECD, CD experiments and X-ray diffraction analysis. Lycojaponicumin D (<b>1</b>) possesses an unprecedented 5/7/6/6 tetracyclic skeleton formed by an unusual C3–C13 linkage, which is first reported in <i>Lycopodium</i> alkaloids. The plausible biogenetic pathway of <b>1</b> is proposed