Methyl 2-(4a,8-Dimethyl-7-oxodeca­hydro­naphthalen-2-yl)acrylate

The title compound, C₁₆H₂₄O₃, was isolated from the aerial part of Inula Viscosa­ (L) Aiton [or Dittrichia Viscosa­ (L) Greuter]. The mol­ecule contains two fused (trans) six-membered rings which both exibit a chair conformation. In the crystal, mol­ecules are linked into chains along [100] by weak C—H...O hydrogen bonds involving the methyl and carbonyl groups.