InChI=1S/C17H14O8/c1-24-14-6-9(2-4-11(14)18)7-15(17(22)23)25-13-5-3-10(16(20)21)8-12(13)19/h2-8,18-19H,1H3,(H,20,21)(H,22,23)/b15-7-