InChI=1S/C19H18O7S/c1-12(2)3-6-14-9-13(5-8-18(14)26-27(23,24)25)4-7-15-10-16(20)11-17(21)19(15)22/h3-11,20-22H,1H2,2H3,(H,23,24,25)/b6-3+,7-4+