Sesquiterpenoids from the roots and rhizomes of Valeriana amurensis and their effects on NGF-induced neurite outgrowth in PC12 cells.

Two new sesquiterpenoids, including a kessane-type sesquiterpenoid (1) and one bisabolane derivative (2), together with fourteen known sesquiterpenoids (3-16), were isolated from the roots and rhizomes of Valeriana amurensis. The structures of new compounds were established on the basis of extensive spectroscopic analysis. All isolates were evaluated for their effects on nerve growth factor (NGF)-mediated neurite outgrowth in pheochromocytoma (PC12) cells. As a results, four compounds including 10-12 and 15 showed potent promoting effects at the concentration of 10 µM on NGF-induced neurite outgrowth in PC12 cells with the differentiation rate of 11.84%, 12.21%, 13.77% and 12.16%, respectively.