InChI=1S/C21H26N2O7/c24-11-17-18(26)19(27)20(28)21(30-17)29-16-9-13-4-8-23(14(13)10-15(16)25)7-3-12-1-5-22-6-2-12/h1,3,5,7,9-10,17-21,24-28H,2,4,6,8,11H2/p+1/t17-,18-,19+,20-,21?/m1/s1