InChI=1S/C18H18O11S/c1-26-12-8-9(5-7-11(12)29-30(23,24)25)4-6-10(19)13-14(20)17(27-2)16(22)18(28-3)15(13)21/h4-8,20-22H,1-3H3,(H,23,24,25)