InChI=1S/C21H20O12/c22-9-3-8(1-2-12(24)15-13(25)6-10(23)7-14(15)26)4-11(5-9)32-21-18(29)16(27)17(28)19(33-21)20(30)31/h1-7,16-19,21-23,25-29H,(H,30,31)/b2-1+