InChI=1S/C20H22O7S/c1-26-19-6-2-4-15(12-19)8-10-17(21)14-18(22)11-9-16-5-3-7-20(13-16)27-28(23,24)25/h2-7,12-13H,8-11,14H2,1H3,(H,23,24,25)