Abstract
Three new germacrane-type sesquiterpenoids, heishuixiecaoline A-C (compounds 1-3), were isolated along with ten known compounds 4-13 from fraction of Valeriana amurensis roots and rhizomes effective against Alzheimer's disease (AD). The structures of 1-3 were elucidated on the basis of their spectroscopic data. We also investigated the protective effect of compounds 1-13 on the neurotoxicity of PC12 cells induced by amyloid-beta (Aβ(25-25)), respectively. As a result, germacrane-type sesquiterpenoids 1-4 and lignans 5-7 were seen to afford protection against Aβ-induced toxicity in PC 12 cells. This study will contribute to revealing the chemical basis for the therapeutic effect of V. amurensis against AD.