InChI=1S/C21H20O10/c22-8-17-18(26)19(27)20(28)21(31-17)30-16-7-10(23)6-15-11(16)2-4-14(29-15)9-1-3-12(24)13(25)5-9/h1-7,17-22,26-28H,8H2,(H2-,23,24,25)/p+1/t17-,18-,19+,20-,21-/m1/s1