InChI=1S/C18H16O7S/c1-2-13(11-7-9-12(10-8-11)25-26(21,22)23)16-17(19)14-5-3-4-6-15(14)24-18(16)20/h3-10,13,19H,2H2,1H3,(H,21,22,23)