Neolignans from Aristolochia fordiana Prevent Oxidative Stress-Induced Neuronal Death through Maintaining the Nrf2/HO-1 Pathway in HT22 Cells

Bioassay-guided fractionation of the ethanolic extract of the stems of Aristolochia fordiana led to the isolation of six new dihydrobenzofuran neolignans (1–3 and 7–9), three new 2-aryldihydrobenzofurans (4–6), a new 8-O-4′ neolignan (10), and 14 known analogues (11–24). The structures of compounds 1–10 were established by spectroscopic methods, and their absolute configurations were determined by analyses of the specific rotation and electronic...