InChI=1S/C19H20O8S/c1-12(11-27-28(24,25)26)2-6-15-17(21)9-14(10-18(15)22)4-3-13-5-7-16(20)19(23)8-13/h2-10,12,20-23H,11H2,1H3,(H,24,25,26)/b4-3+,6-2+