Vicinal Diol Sesquiterpenes from Cinnamomum migao with Neuroprotective Effects in PC12 Cells.

In the ongoing search for new vicinal diol natural products, four new (Migaones A-D, 1 - 4 ) and four known ( 5 - 8 ) vicinal diol sesquiterpenoids were isolated from the branches and leaves of Cinnamomum migao . Their structures were unequivocally determined by comprehensive spectroscopic analyses (HRESIMS, 1D, and 2D NMR), single-crystal X-ray diffraction, electronic circular dichroism calculations, and comparison with existing literature data. All compounds isolated from C. migao possess vicinal diol structural units except compound 2 . The newly isolated compounds ( 1 - 4 ) were evaluated for their neuroprotective activity using the PC12 cell injury model induced by N -methyl-daspartate acid (NMDA) and compounds 1 - 2 showing moderate neuroprotective activity against NMDA-induced neurotoxicity. Furthermore, molecular docking studies indicated that the most active compound 2 binds to the active site of the NMDA receptor via hydrogen bonds and hydrophobic interactions.