A re-examination of the oxidation of hydroxyeremophilone has disclosed that the product of the oxidation formerly regarded as having the composition C₁₂H₁₈O₃ is really a compound C₁₆H₂₂O₄. The structure advanced for this substance is in full accord with and constitutes additional evidence in support of the "unnatural" (non-isoprenoid) skeleton for hydroxyeremophilone.