InChI=1S/C17H17NO8S/c19-13-5-1-11(2-6-13)3-8-17(22)18-10-16(26-27(23,24)25)12-4-7-14(20)15(21)9-12/h1-9,16,19-21H,10H2,(H,18,22)(H,23,24,25)/b8-3+