Arthpyrones A–C, Pyridone Alkaloids from aSponge-Derived Fungus Arthrinium arundinisZSDS1-F3.

Threenew 4-hydroxy-2-pyridone alkaloids, arthpyrones A–C(1–3), were isolated from the sponge-derivedfungus Arthrinium arundinisZSDS1-F3. Their structureswere elucidated on the basis of spectroscopic analysis, CD spectra,quantum chemical calculation, and X-ray single-crystal diffractionanalysis. Compounds 1and 2possessed a2-pyridone core featured with a decalin moiety linked via a carboxidebridge bearing a novel oxabicyclo[3.3.1]nonane ring system rarelydiscovered in nature. A possible biosynthetic pathway for them wasproposed. [ABSTRACT FROM AUTHOR]