InChI=1S/C21H20O8S/c1-21(13-28-30(24,25)26)12-11-17-19(29-21)10-6-15(20(17)27-2)5-9-18(23)14-3-7-16(22)8-4-14/h3-12,22H,13H2,1-2H3,(H,24,25,26)