Laggeric Acid, a Novel Seco-eudesmane Sesquiterpenoid from Laggera Crispata

Laggeric acid (1), a novel 4,5-seco-eudesmane sesquiterpene acid, along with 19 known compounds, was isolated from the MeOH extract of the whole plant of Laggera crispata. The structure of 1 was elucidated to be (4S,5S*,7R*,10R*)-4,5-seco-4,5-dihydroxy-11(13)-eudesmen-12-oic acid on the basis of spectroscopic analysis and a convenient Mosher's method.