The title compound, C15H22O3·H2O, is a natural producr isolated from Chloranthus japonicus, which is a eudesmane sesquiterpenoid. The two trans-fused six-membered rings have chair confomations. In the crystal, O-H⋯O hydrogen bonds link the components into corrugated layers parallel to the bc plane. There are C-H⋯O inter-actions present within and between the layers.
Keywords: Chloranthus japonicus; crystal structure; eudesmane sesquiterpenoid; hydrogen bonds.