Penijanacoranes A—F, Acorane‐Type Sesquiterpenes from a Deep Sea‐Derived Fungus <i>Penicillium janthinellum</i><scp>SH0301</scp>

Comprehensive Summary Six new acorane‐type sesquiterpenes, named penijanacoranes A—F ( 1 — 6 ), as well as one known eudesmane sesquiterpenoid 1 α ,6 β ,11‐eudesm‐triol ( 7 ) have been isolated from a deep‐sea‐derived fungus Penicillium janthinellum SH0301. Their structures and absolute configurations were established by the comprehensive spectroscopic analysis, TDDFT‐ECD calculations, and X‐ray diffraction. Penijanacorane A ( 1 ) was identified as a rare acorane‐type sesquiterpene lactone featuring a novel 6/5/6 tricyclic system, while penijanacoranes E and F ( 5 and 6 ) represented undescribed examples of nor‐acorane sesquiterpenes at C‐1. Penijanacorane C ( 3 ) exhibited significant inhibitory activity against LPS‐induced NO production in Raw264.7 macrophages with an IC 50 value of 6.23 μM, which was more potent than that of positive control dexamethasone (IC 50 = 11.49 μM). This study expanded the chemical diversity of acorane‐type sesquiterpenoids and revealed that compound 3 was a potential molecule for anti‐inflammatory agents.