InChI=1S/C18H20O10/c1-2-3-4-9-8-5-7(19)6-10(11(8)17(25)26-9)27-18-14(22)12(20)13(21)15(28-18)16(23)24/h4-6,12-15,18-22H,2-3H2,1H3,(H,23,24)/b9-4+