InChI=1S/C17H17NO8S/c19-14-5-8-17(22,11-15(14)20)9-6-16(21)18-10-7-12-1-3-13(4-2-12)26-27(23,24)25/h1-6,8-9,11,20,22H,7,10H2,(H,18,21)(H,23,24,25)/b9-6+