Guaiane Type Sesquiterpenoids from the Roots of Daphne genkwa and Evaluation of Their Neuroprotective Effects.
Chromatographic purification of the roots of Daphne genkwa led to 11 new guaiane type sesquiterpenoids (1 11) named genkwanoids A K, and six known analogues (12 17) A comprehensive set of spectroscopic methods including IR, UV, HRESIMS, and 1D/2D NMR were used to elucidate the structures and relative configurations of 1 11. The absolute configurations were determined by the optical rotation calculations and the modified Mosher's method. The possible biosynthetic pathways for 1 11 are proposed. Furthermore, the neuroprotective effects of 1 17 on H2O2 induced damage in human neuroblastoma SH SY5Y cells were screened using an MTT assay. Compounds 9, 10, and 16 exhibited moderate neuroprotective effects, with survival rates of 79.34% 79.94% and 75.64% after treatment with 12.5 mM, values that were comparable to the positive control, Trolox (78.65% Furthermore, annexin V FITC/PI staining of cells treated with 9, 10, and 16 showed that the neuroprotective effects of these compounds may arise from inhibiting cell apoptosis.
Journal of natural products