InChI=1S/C18H17NO6S/c1-18(2)7-6-12-15-13(11-4-3-5-14(20)16(11)19-15)8-10(17(12)25-18)9-24-26(21,22)23/h3-8,19-20H,9H2,1-2H3,(H,21,22,23)