Two new monoterpenoids from the roots of Paeonia lactiflora and their neuroprotective activities

Seven monoterpenoids were isolated and elucidated from the roots of Paeonia lactiflora, including two new derivatives (1 and 2), along with five known compounds (3-7). The structures of the new compounds (1 and 2) were determined by HR-ESI-MS, UV, and NMR spectroscopic data analyses. Moreover, all isolates were tested for their neuroprotective activities against H2O2-induced injury in PC12 cells. As a result, compound 5 displayed moderate neuroprotective activity and increased PC12 cell viability from 50 ± 2.52 % to 73 ± 1.54 % at 100 μM.