6β-Acet­oxy-1α,7β,11β,15β-tetra­hydr­oxy-7α,20-ep­oxy-ent-kaur-16-ene

The title compound, C22H32O7, a natural ent-kaurane diterpenoid also referred to as Maoyecrystal F, was obtained from the medicinal plant Isodon nervosa. There are four rings with the expected cis and trans junctions. Cyclohexane ring A adopts a chair conformation, rings B and C adopt boat conformations, while the five-membered ring has an envelope conformation. The mol­ecules stack along the a axis in the crystal and are linked together by inter­molecular O—H⋯O hydrogen bonds.