Anti-inflammatory Sesquiterpenoids from a Sponge-Derived Fungus Acremonium sp.

In the course of our search for bioactive metabolites from a sponge-derived fungus Acremonium sp., new sesquiterpenoids (1−4) were isolated along with known derivatives by bioactivity-guided fractionation. The unique cyclic skeleton of compounds 2 and 3 is unprecedented. The absolute configurations were determined by modified Mosher’s method and CD spectroscopy, along with comparison of 1H and 13C NMR spectroscopic data and specific optical rotation values with those reported. The anti-inflammatory activity of the isolated compounds (1, 5, 7−13) was evaluated by measuring their inhibitory effects on the production of pro-inflammatory mediators (NO, IL-6, and TNF-α) in RAW 264.7 murine macrophage cells. Among the compounds tested, compounds 7 and 9 significantly inhibited the production of NO and TNF-α at the concentration of 100 μM, while compounds 11 and 12 showed selective inhibition of NO production at the same concentration.