InChI=1S/C20H18O6S/c1-25-17-11-14-4-2-3-13-7-10-16(19(18(13)14)20(17)21)12-5-8-15(9-6-12)26-27(22,23)24/h2-10,17,20-21H,11H2,1H3,(H,22,23,24)