3β-Acet­oxy-8β,10β-dihy­droxy-6β-meth­oxy­eremophil-7(11)-en-8,12-olide

The title compound, C(18)H(26)O(7), is an eremophilenolide which has been isolated from the plant Ligularia duciformis for the first time. The present study confirms the atomic connectivity assigned on the basis of (1)H and (13)C NMR spectroscopy. The mol­ecule contains three fused rings, two six-membered rings in chair confomations and a five-membered ring in a flattened envelope conformation. Two hy­droxy groups are involved in formation of intra- and inter­molecular O—H⋯O hydrogen bonds. The latter ones link mol­ecules into chains propagating in [010].