InChI=1S/C20H25NO7S/c1-2-3-4-11-28-16-7-5-15-13-17(8-6-14(15)12-16)29(26,27)21-18(20(24)25)9-10-19(22)23/h5-8,12-13,18,21H,2-4,9-11H2,1H3,(H,22,23)(H,24,25)/t18-/m1/s1