In the title compound, C21H28O4·H2O, the cyclo­hexa­dienone ring is planar (r.m.s. deviation 0.0186 Å), whereas the two cyclo­hexane rings and the cyclo­hexa­none ring adopt chair conformations. The crystal structure is stabilized by O—H⋯O and C—H⋯O hydrogen bonds.

The title compound C23H26O7, was prepared by esterification of 2-ethyl-7-hydr­oxy-8-methoxy­methyl-4H-chromen-4-one with (S)-(−)-camphanic chloride. The two rings of the chromone system are coplanar, making a dihedral angle of 1.99 (19)°, and the camphanoyl unit substituted at 7-O retains the original bicyclo­[2.2.1]heptane conformation of the starting reagent.