InChI=1S/C18H12O7/c19-6-3-8-12(10(20)4-6)16(23)14-9(15(8)22)5-11(21)13-7-1-2-24-18(7)25-17(13)14/h3-5,7,18-21H,1-2H2/t7-,18+/m1/s1