Furanaspermeroterpenes A and B, two unusual meroterpenoids with a unique 6/6/6/5/5 pentacyclic skeleton from the Marine-derived fungus Aspergillus terreus GZU-31-1

Furanaspermeroterpenes A (1) and B (2), with a unique 6/6/6/5/5 pentacyclic skeleton, and five new congeners aspermeroterpenes D-H (3-7) were co-isolated from the marine-derived fungus Aspergillus terreus GZU-31-1. Among them, compounds 1 and 2 with rare five-membered D/E coupling rings were the first example of DMOA-derived meroterpenoids. Moreover, compound 3 was the first reported 6/6/6/6/5 pentacyclic meroterpenoid featuring an unusual...