InChI=1S/C18H14O8/c19-10-4-2-9(7-12(10)21)16-15(18(24)25)14-8(3-6-13(22)23)1-5-11(20)17(14)26-16/h1-7,15-16,19-21H,(H,22,23)(H,24,25)/b6-3-/t15-,16-/m1/s1