Structures and Biological Evaluation of 8,4′-oxyneolignans from the Roots of Platycodon grandifloras

Chemical investigations of Platycodon grandiflorus have resulted in the isolation and identification of seven 8,4'-oxyneolignans, including four undescribed compounds (1-4).The structures of these novel compounds were determined using HR-ESI-MS and NMR (1D and 2D) spectroscopic analyses, combined with ECD calculations.The inhibitory activity of these terpenoids against -glucosidase was also evaluated, and the results revealed that none of the compounds exhibited significant -glucosidase inhibitory activity at a concentration of 50 M.Compared with the positive control, all the compounds displayed weak inhibitory activity, with inhibition rates ranging from 1.06% to 7.31%.