Aspterpenacids A and B, Two Sesterterpenoids from a Mangrove Endophytic Fungus Aspergillus terreus H010

Two new sesterterpenoids, aspterpenacids A (<b>1</b>) and B (<b>2</b>), with an unusual carbon skeleton of a 5/3/7/6/5 ring system were isolated from the mangrove endophytic fungus Aspergillus terreus H010. Their structures were elucidated on the basis of spectroscopic methods, single-crystal X-ray diffraction analysis, and electronic circular dichroism calculations. A biogenetic pathway for <b>1</b> and <b>2</b> is proposed. Both <b>1</b> and <b>2</b> showed no significant antibacterial activity or cytotoxicity at 50 μM.