Eight Breviane‐type Spiroditerpenoids From the Deep‐Sea‐Derived Fungus <i>Penicillium olsonii</i> SCSIO41803

Eight new breviane-type spiroditerpenoids penolsones A-H (1-8) along with a known analogue niveulone (9) were isolated from the deep-sea-derived fungus Penicillium olsonii SCSIO41803. Their structures were determined by extensive spectroscopic analysis, and their absolute configurations were further confirmed by comparisons of experimental electronic circular dichroism (ECD) spectra with the literature or quantum chemical calculations of ECD spectra. In addition, in vitro experiments showed that 3, 5 and 7 could significantly inhibit the production of lipopolysaccharide-induced nitric oxide in RAW264.7 cells without significant cytotoxicity.