Antineuroinflammatory constituents from the root extract of Paris verticillata

Two new cyclopropanoic fatty acid glycosides, named parisveroside A (1) and parisveroside B (2), were isolated from a MeOH extract of the roots of Paris verticillata (Liliaceae) together with three other known compounds, salicin (3), 3-(-d-glucopyranosyloxymethyl)-2-(4-hydroxy-3-methoxyphenyl)-5-(3- hydroxypropyl)-7-methoxy-(2R,3S)-dihydrobenzofuran (4), and allantoin (5). Their structures were elucidated on the basis of spectroscopic data, including 1D and 2D NMR, HR-FAB-MS, and chemical evidence. To investigate the antineuroinflammatory effects of the isolated compounds (1-5), nitric oxide (NO) production was evaluated in the lipopolysaccharide-activated microglia cell line, BV-2. Compounds 2 and 4 significantly inhibited NO production with IC ₅₀ values of 74.8 and 60.5 mol/L, respectively.