Abstract
The title compound, C29H32O13, is a potent antitumor drug. Its crystal belongs to space group P21 with cell dimensions a = 11.527(4), b = 6.215(2), c = 21.670(7)Å, and β = 100.60(3)°. The final R value is 0.099. The characteristic four-ring system of the aglycone moiety takes a slightly curved structure with the dihedral angle between the two five-membered rings at both ends being 12(1)°. Both the pyranose and 1,3-dioxane rings take chair conformations.
