InChI=1S/C19H20O6S/c20-17-12-10-15(11-13-17)6-4-5-9-18(21)14-19(25-26(22,23)24)16-7-2-1-3-8-16/h1-3,5,7-13,19-20H,4,6,14H2,(H,22,23,24)/b9-5+