InChI=1S/C19H20O6S/c20-17-10-7-16(8-11-17)14-19(25-26(22,23)24)13-12-18(21)9-6-15-4-2-1-3-5-15/h1-5,7-8,10-13,19-20H,6,9,14H2,(H,22,23,24)/b13-12+