Phellilane L, Sesquiterpene Metabolite of <i>Phellinus linteus</i>: Isolation, Structure Elucidation, and Asymmetric Total Synthesis

A new cyclopropane-containing sesquiterpenoid, phellilane L (<b>1</b>), was isolated from the medicinal mushroom <i>Phellinus linteus</i> (“Meshimakobu” in Japanese), a member of the Hymenochaetaceae family and a well-known fungus that is widely used in East Asia. The planar structure of <b>1</b> was determined on the basis of spectroscopic analysis. The authors achieved the first total synthesis of <b>1</b>. Our protecting group-free synthesis features a highly stereoselective one-pot synthesis involving an intermolecular alkylation/cyclization/lactonization strategy for construction of the key cyclopropane-γ-lactone intermediate. Additionally, our synthesis determined the absolute configuration of phellilane L (<b>1</b>)