InChI=1S/C18H18O9/c1-6-7(2)12(20)10-8(11(6)19)4-3-5-9(10)26-18-15(23)13(21)14(22)16(27-18)17(24)25/h3-5,13-16,18,21-23H,1-2H3,(H,24,25)