Lycopodium Alkaloids from Huperzia serrata

Three new lycopodium alkaloids, huperserramines A-C (1-3, resp.), along with 15 known ones, lycopodine-6,11-diol (4), lycoposerramine H (5), lycoposerramine I (6), lycopodine-6-ol (7), lycoposerramine M (8), diphaladine A (9), lycoposerramine K (10), lycoposerramine W (11), huperzine M (12), luciduline (13), phlegmariuine N (14), huperzine A (15), huperzine B (16), lycodine (17), and lycoposerramine R (18), were isolated from the whole plant of Huperzia serrata. Their structures were established by spectroscopic methods, including 2D-NMR and MS analyses. All the isolates were evaluated for their inhibitory effects on acetylcholinesterase (AChE) and -glucosidase. As a result, lycopodine-6,11-diol (4) exhibited more potent -glucosidase inhibitory activity (IC50 148 +/- 5.5M) than the positive control acarbose (IC50 376.3 +/- 2.7M).