InChI=1S/C18H14O8/c19-2-1-7-13-11(26-18(7)25)5-9-14(17(13)24)16(23)12-8(15(9)22)3-6(20)4-10(12)21/h3-5,7,18-21,24-25H,1-2H2/p-1/t7-,18-/m0/s1