InChI=1S/C21H20O9/c22-7-14-17(26)18(27)19(28)21(30-14)15-13(24)6-5-11-16(25)12(8-29-20(11)15)9-1-3-10(23)4-2-9/h1-6,8,14,17-19,21-24,26-28H,7H2