InChI=1S/C18H14O7/c1-21-9-2-3-10-12(4-9)25-16-7-22-13-6-15-14(23-8-24-15)5-11(13)18(16,20)17(10)19/h2-6,16,20H,7-8H2,1H3/t16-,18-/m1/s1