Seven new neuroprotective sesquineolignans isolated from the seeds of Crataegus pinnatifida

Abstract The investigation of the ethanol extract of the seeds of Crataegus pinnatifida led to the isolation of seven new 8- O -4′ type sesquineolignans crasesquineolignan A–G ( 1 – 7 ), along with a reported analogue, leptolepisol B ( 8 ). The chemical structures of these compounds were elucidated based on complex analysis of their MS, 1D and 2D NMR data. All the isolated compounds were tested for their neuroprotective effects against the damage of human neuroblastoma SH-SY5Y cells induced by H 2 O 2 , and most of them showed significant neuroprotective activity. Among them, compound 4 (77.58%) showed the best protective effect, even better than the positive control (69.26%) at 25 μM.