Neuroprotective xanthone glycosides from Swertia punicea.

Two new dimeric xanthone O-glycosides, puniceasides A (1) and B (2), a new trimeric O-glycoside, puniceaside C (3), and two new trimeric C-glycosides, puniceasides D (4) and E (5), together with 12 known xanthones were isolated from the entire plant of Swertia punicea. The structures of 1-5 were determined by HRESIMS and NMR spectroscopic methods. Compounds 2, 6, and 7 exhibited potent neuroprotective activity against H(2)O(2)-induced PC12 cell damage.