InChI=1S/C21H20O11/c1-29-15-3-8(2-12(24)17(15)26)20-16(32-21-19(28)18(27)13(25)7-30-21)6-10-11(23)4-9(22)5-14(10)31-20/h2-6,13,18-19,21,25,27-28H,7H2,1H3,(H3-,22,23,24,26)/p+1/t13-,18+,19-,21-/m1/s1