Résumé : C30H32O10, monoclinic, P21/c, a = 12.932(5), b = 9.670(6), c = 23.276(13)Å, β = 103.87(4), ν = 2825.9(25)Å3, Mr = 552.58, Z = 4, Dx = 1.30 mg cm−3. The structure was solved by direct methods (MULTAN 80) and refined (SHELX 76) to a final R value of 0.056 for 2344 observed reflections. The dioxane ring has a chair conformation. On this ring, two substituents, the phenyl and the methylenedioxyphenyl groups, are in equatorial positions while the substituted ethyl fragment is axial. Copyright © 1984 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim