InChI=1S/C18H19NO8S/c1-26-16-10-12(2-8-15(16)21)3-9-18(22)19-11-17(27-28(23,24)25)13-4-6-14(20)7-5-13/h2-10,17,20-21H,11H2,1H3,(H,19,22)(H,23,24,25)