Chemical Constituents of the Fruits of Cornus officinalis and Evaluation of Their Neuroprotective Activity

The phytochemical investigation of the fruits of Cornus officinalis yielded a new phenolic acid derivative, neophenolic acid A (1), and a novel flavonoid glycoside, (2R)‐naringenin‐7‐O‐β‐(6″‐galloyl‐glucopyranoside) (2a), along with six known flavonoid glycosides (2b – 7). Their structures were determined by 1D, 2D NMR and HRESIMS data. The absolute configuration of 1 was established by ECD analysis. Compounds 1 – 7 were evaluated for their neuroprotective activities against corticosterone (CORT)‐induced injury in PC‐12 cells. Compounds 1, 2a, 2b, 5, and 6 exhibited neuroprotective activities against CORT‐induced neurotoxicity in PC‐12 cells. The underlying mechanism study suggested that compounds 1, 2a, 2b, 5, and 6 were able to attenuate CORT‐induced apoptosis and damage, increase the levels of MMP and decrease Ca2+ inward flow in PC‐12 cells.