InChI=1S/C18H20O6/c1-21-11-7-15(22-2)12-9-17(23-3)18(24-16(12)8-11)10-4-5-13(19)14(20)6-10/h4-8,17-20H,9H2,1-3H3/t17-,18-/m1/s1