InChI=1S/C18H22O9/c1-2-3-6-9-11-8(17(24)25-9)5-4-7-10(11)26-18-14(21)12(19)13(20)15(27-18)16(22)23/h4-6,10,12-15,18-21H,2-3,7H2,1H3,(H,22,23)/b9-6+