Lycodine-type alkaloids from Lycopodium casuarinoides

Two new lycodine-type alkaloids, huperzinine N-oxide (1) and 8,15-dihydrohuperzinine (2) as well as five known compounds, huperzinine (3), huperzine B (4), huperzine D (5), N-demethylhuperzinine (6), and beta-obscurine (7), were isolated from the club moss Lycopodium casuarinoides. The structures of I and 2 were elucidated by spectroscopic methods and chemical transformation. The absolute configuration of I was established by chemical correlation with 3, and that of 2 was determined by its CD spectrum.