Ephedplics E-I: three lignans and two benzofuran-type compounds from the roots of Ephedra sinica Stapf and their neuroprotective activity.

Five new compounds Ephedplics E-I were isolated from the roots of Ephedra sinica Stapf, including three lignans (1-3) and two benzofuran-type compounds (4-5). Their structures were elucidated by spectroscopic methods, involving UV, IR, NMR spectra and HRESIMS analyses. The absolute configuration of compounds 1-5 was determined by comparing their experimental and calculated ECD spectra. All compounds were assessed for their neuroprotective activities against damage induced by corticosterone (CORT) in PC-12 cells. Compounds 1 and 2 were capable of significantly ameliorating CORT-induced PC-12 injury.