Elodexanthones A—J, Isoprenylated Xanthone Derivatives with Diverse Skeletons and Bioactivities from <i>Hypericum elodeoides</i>
Yanbing Mu, Yaqi Li, Qi‐Ji Li, Wen‐Jun Xu, Yunpeng Sun, Siyuan Wang, Letian Cui, Lingyi Kong, Jun Luo
Abstract
Comprehensive Summary Elodexanthones A—J ( 1 — 10 ), two pairs of rearranged isoprenylated xanthone enantiomers with an unprecedent 6/6/5/6 tetracyclic core ( 1 — 2 ) along with seven new isoprenylated xanthones ( 3 — 9 ) and a pair of phenylpropanoid xanthones ( 10 ), were purified and enantio‐separated from the whole plant of Hypericum elodeoides . Their structures including absolute configurations were characterized by the comprehensive analysis of NMR, HRESIMS, NMR calculations, and ECD calculations. Through Bayer‐Villiger oxidation, Claisen condensation and electrophilic addition, the rearranged skeletons of elodexanthones A—B ( 1 — 2 ) were generated from isoprenylated xanthone precursors. The bioactivities evaluation exhibited that compounds 3 , 5 , 8 — 10 showed anti‐inflammatory activity with the IC 50 values in the range of 9.53—34.39 μmol/L, and compounds 3 — 7 , and 9 showed notable α ‐glucosidase inhibitory activity (IC 50 : 6.02—257.11 μmol/L).