InChI=1S/C21H20O9/c1-30-11-4-2-3-8-14(11)20(28)16-15(17(8)25)18(26)9-5-21(29,12(24)7-22)6-10(23)13(9)19(16)27/h2-4,10,12,22-24,26-27,29H,5-7H2,1H3/t10-,12?,21-/m0/s1