InChI=1S/C19H20O6S/c1-13(2)3-10-17-18(20)11-15(12-19(17)21)5-4-14-6-8-16(9-7-14)25-26(22,23)24/h3-13,20-21H,1-2H3,(H,22,23,24)/b5-4+,10-3+