InChI=1S/C18H13NO7/c20-12-4-11(18(23)19-7-16(21)22)3-10-6-14(26-17(10)12)9-1-2-13-15(5-9)25-8-24-13/h1-6,20H,7-8H2,(H,19,23)(H,21,22)