Chiral resolution and neuroprotective activities of enantiomeric 8-O-4' neolignans from the fruits of Crataegus pinnatifida Bge.
Fitoterapia. 2019 May 6. Epub 2019 May 6. PMID: 31071436
Five pairs of enantiomeric 8-O-4' neolignans (1a/1b-5a/5b), including seven new compounds (1a/1b, 2a, 3a, 4a/4b and 5b), were obtained from the fruits of Crataegus pinnatifida Bge. Their structures were determined by comprehensive spectroscopic analyses. The absolute configurations of the enantiomers were determined by comparison of the experimental ECD with the calculated data. Additionally, all the enantiomeric neolignans were evaluated for their neuroprotective activity against HO-induced cell injury in human neuroblastoma SH-SY5Y cells, and most of them showed potent selective neuroprotective activity. Especially, 3b (72.98%) showed the best protective effect, better than 3a (63.49%) and trolox (62.86%) at 25 μM.