InChI=1S/C17H17NO7S/c19-16(11-12-5-2-1-3-6-12)18-15(17(20)21)10-13-7-4-8-14(9-13)25-26(22,23)24/h1-9,15H,10-11H2,(H,18,19)(H,20,21)(H,22,23,24)