Delitschiapyrone A, a Pyrone–Naphthalenone Adduct Bearing a New Pentacyclic Ring System from the Leaf-Associated Fungus <i>Delitschia</i> sp. FL1581 Jian-Guang Luo Xiao-Bing Wang Ya-Ming Xu Jana M. U’Ren A. Elizabeth Arnold Ling-Yi Kong A. A. Leslie Gunatilaka 10.1021/ol502973c.s001 https://acs.figshare.com/articles/journal_contribution/Delitschiapyrone_A_a_Pyrone_Naphthalenone_Adduct_Bearing_a_New_Pentacyclic_Ring_System_from_the_Leaf_Associated_Fungus_i_Delitschia_i_sp_FL1581/2044269 Delitschiapyrone A (<b>1</b>), an α-pyrone–naphthalenone adduct with an unprecedented pentacyclic ring system, was isolated from a solid culture of the leaf-associated fungus <i>Delitschia</i> sp. FL1581. The structure of <b>1</b> was elucidated by spectroscopic analysis and X-ray crystallography, and its absolute configuration was defined by experimental and calculated ECD. Biosynthetically, the unique 6/6/5/7/6 pentacyclic core of <b>1</b> may be formed by an intermolecular Diels–Alder-type addition of the precursors derived from (1′<i>R</i>)-2′,3′-dihydropyrenocine C (<b>2</b>) and 6-ethyl-2,7-dimethoxyjuglone (<b>3</b>) found to co-occur with <b>1</b> in this fungus. 2015-12-17 05:57:20 adduct spectroscopic analysis culture pentacyclic ring system crystallography ethyl Biosynthetically FL 1581. core Diel Bearing fungus ECD Pyrone configuration Adduct precursor FL 1581Delitschiapyrone Fungu New Pentacyclic Ring System