10.1021/acs.jnatprod.5b00969.s002 Jinyu Zhang Jinyu Zhang Ling Liu Ling Liu Bo Wang Bo Wang Yang Zhang Yang Zhang Lili Wang Lili Wang Xingzhong Liu Xingzhong Liu Yongsheng Che Yongsheng Che Phomanolides A and B from the Fungus <i>Phoma</i> sp.: Meroterpenoids Derived from a Putative Tropolonic Sesquiterpene via Hetero-Diels–Alder Reactions American Chemical Society 2015 culture Compound 4 NMR spectroscopic data eupenifeldin crystallography dichroism calculations phomanoxide Derived ReactionsPhomanolide biosynthetic precursor antiproliferative effects IC 50 values compounds 1 Putative Tropolonic Sesquiterpene monotropolonic sesquiterpene fungus Biogenetically pentacyclic Phomanolide substrate Meroterpenoid tetracyclic skeletons Phoma Fungu meroterpenoid glioma cell lines 2015-12-24 00:00:00 Dataset https://acs.figshare.com/articles/dataset/Phomanolides_A_and_B_from_the_Fungus_i_Phoma_i_sp_Meroterpenoids_Derived_from_a_Putative_Tropolonic_Sesquiterpene_via_Hetero_Diels_Alder_Reactions/2095045 Phomanolides A (<b>1</b>) and B (<b>2</b>), unique meroterpenoids with new pentacyclic and tetracyclic skeletons, respectively, and phomanoxide (<b>3</b>), the double-epoxidation product of a putative biosynthetic precursor of <b>1</b> and <b>2</b>, were isolated from the solid substrate fermentation cultures of the fungus <i>Phoma</i> sp., along with the known compound eupenifeldin (<b>4</b>). The structures of <b>1</b>–<b>3</b> were elucidated based on NMR spectroscopic data and electronic circular dichroism calculations and further secured by X-ray crystallography. Biogenetically, compounds <b>1</b> and <b>2</b> could be derived from a hypothetical monotropolonic sesquiterpene intermediate via hetero-Diels–Alder reactions. Compound <b>4</b> showed potent antiproliferative effects against three human glioma cell lines, with IC<sub>50</sub> values of 0.08–0.13 μM.