Peroneutone A, a new highly oxygenated diterpenoid with diverse biological activities from <i>Peroneutypa scoparia</i>

<jats:p>A chemical investigation of the endophytic fungus Peroneutypa scoparia RJHH-3 led to the isolation of a new highly oxygenated pimarane diterpenoid, peroneutone A (1), together with three known analogues, scopararane C (2), libertellenone A (3), and 9&amp;#x03B1;-hydroxyisopimara-8(14),15-dien-7-one (4). The structure of 1 was established by HRESIMS and extensive NMR analyses, while its stereochemistry was determined by NOESY, NMR calculations, DP4&amp;#x002B; analysis, and ECD calculations. Compounds 1&amp;#x2013;4 showed antifungal and anti-inflammatory activities, and 1 exhibited the strongest inhibition against Candida albicans (MIC &amp;#x003D; 0.6 &amp;#x03BC;M) together with selective cytotoxicity toward A549 cells (IC50 &amp;#x003D; 6.9 &amp;#x03BC;M). These findings expand the chemical and biological diversity of pimarane diterpenoids from P. scoparia.</jats:p>