InChI=1S/C21H20O11/c22-7-15-18(27)19(28)20(29)21(32-15)31-12-3-1-2-9(24)17(12)14-6-11(26)16-10(25)4-8(23)5-13(16)30-14/h1-6,15,18-25,27-29H,7H2/t15-,18-,19+,20-,21-/m1/s1