Sarcotrine G, a New Derivative Isolated from a Marine Sponge Sarcotragus Species

Four sesterterpenoids were isolated from AMPK activity-guided fraction of marine sponge Sarcotragus species. Their planar structures were determined from combination of extensive 1D and 2D NMR experiments and MS data, and the configuration at the chiral centers were assigned by comparison with the and chemical shifts of the known compounds. Among four compounds, compound 2 was found to be a new sarcotrine derivative. Though not strong, compounds 1-4 moderately showed AMPK activation effect on L6 myoblast cell through Western Blot analysis.