InChI=1S/C21H20O11/c1-29-13-4-8(2-3-10(13)23)19-20(32-21-18(28)16(26)12(25)7-30-21)17(27)15-11(24)5-9(22)6-14(15)31-19/h2-6,12,16,18,21-26,28H,7H2,1H3/t12-,16+,18-,21+/m1/s1