InChI=1S/C20H18O9S/c1-26-18-8-19-15(3-2-11(9-27-19)10-28-30(23,24)25)20-16(18)7-17(29-20)12-4-13(21)6-14(22)5-12/h2,4-8,21-22H,3,9-10H2,1H3,(H,23,24,25)