A pair of enantiomeric 5-oxabicyclic[4.3.0]lactam derivatives and one new polyketide from the marine-derived fungus <i>Penicillium griseofulvum</i>

<p>A pair of enantiomeric 4-oxabicyclic[4.3.0]lactam derivatives, (+)- and (−)-penicilactam A (<b>1</b>), and one new polyketide derivative penicitrinone F (<b>2</b>) were isolated from the marine-derived fungus <i>Penicillium griseofulvum</i> GT-10. Their structures and absolute configurations were elucidated through extensive spectroscopic analyses combined with the calculated ECD spectra. Penicitrinone F (<b>2</b>) had moderate inhibitory activity towards <i>Bacillus subtilis</i> with a MIC value of 6.3 μM.</p>