Anti-neuroinflammatory sesquiterpenoids from .

Hupelactones A () and B (), two new eudesmanolide-type enantiomers of the corresponding compounds, along with four mono- (-) and nine dimeric- (-) known sesquiterpenoids were isolated from the whole plant of var. . The new structures including the absolute configurations were determined by comparison with previously reported enantiomers, extensive spectroscopic methods in combination with electronic circular dichroism (ECD) calculations. All the isolates were evaluated for their inhibitory activities against the lipopolysaccharide (LPS)-induced nitric oxide (NO) production in murine BV-2 microglial cells. Among them, the dimeric lindenane sesquiterpenoids shizukaols F () and G () exhibited the most potent activities, with IC values of 2.65 and 4.60 μM, respectively.