Rearranged Terpenoids from the Marine Sponge Darwinella cf. oxeata and Its Predator, the Nudibranch Felimida grahami.
Maria Camila A RamirezDavid E WilliamsJuliana R GubianiLizbeth L L ParraMario F C SantosDaiane D FerreiraJuliana T MesquitaAndre G TemponeAntonio G FerreiraVinícius PadulaEduardo HajduRaymond J AndersenRoberto G S BerlinckPublished in: Journal of natural products (2017)
Marine sponges are a rich source of terpenoids with rearranged spongian carbon skeletons. Investigation of extracts from the sponge Darwinella cf. oxeata yielded four new rearranged diterpenoids, oxeatine (2) and oxeatamides H-J (3-5), as well as the known metabolites oxeatamide A (6), oxeatamide A methyl ester (7), and membranolide (1). Oxeatine (2) has a new heterocyclic skeleton, while oxeatamide J (5) has an N-methyl urea group included in a γ-lactam moiety. UPLC-QTOF analysis of the extract obtained from the mantle of the nudibranch Felimida grahami indicated the presence of 1 and 4.