Asperterpenols A and B, New Sesterterpenoids Isolated from a Mangrove Endophytic Fungus <i>Aspergillus</i> sp. 085242

Asperterpenol A (<b>1</b>) and asperterpenol B (<b>2</b>), two novel sesterterpenoids with an unusual 5/8/6/6 tetracyclic ring skeleton, were isolated from a mangrove endophytic fungus <i>Aspergillus</i> sp. 085242. The structures were elucidated on the basis of spectroscopic methods and the absolute configurations determined by single-crystal X-ray diffraction analysis. Compounds <b>1</b> and <b>2</b> inhibit acetylcholinesterase with IC₅₀ values of 2.3 and 3.0 μM, respectively