Penijanacoranes A—F, Acorane‐Type Sesquiterpenes from a Deep Sea‐Derived Fungus Penicillium janthinellumSH0301

Abstract

Comprehensive SummarySix new acorane‐type sesquiterpenes, named penijanacoranes A—F (1—6), as well as one known eudesmane sesquiterpenoid 1α,6β,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 IC50 value of 6.23 μM, which was more potent than that of positive control dexamethasone (IC50 = 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.