InChI=1S/C21H20O10/c22-8-17-18(26)19(27)20(28)21(31-17)29-10-2-3-11-13(24)7-15(30-16(11)6-10)9-1-4-12(23)14(25)5-9/h1-7,17-23,25-28H,8H2/t17-,18-,19+,20-,21-/m1/s1