Sordarin Diterpene Glycosides with an Unusual 1,3-Dioxolan-4-one Ring from the Zoanthid-Derived Fungus TA26-15.

Six new sordarin tetracyclic diterpene glycosides, moriniafungins B-G (-), and a new sordaricin tetracyclic diterpene, sordaricin B (), together with two known analogues, moriniafungin () and sordaricin (), were isolated from the zoanthid-derived fungus TA26-15. The structures of the new compounds were elucidated by comprehensive analyses of spectroscopic data, including 1D and 2D NMR and MS data. Compounds - represent the first case of sordarins from marine-derived fungi possessing a sordarose with a spiro 1,3-dioxolan-4-one ring, which is rare in the nature. Compound showed antifungal activity against ATCC10231 with an MIC value of 2.9 μM.