InChI=1S/C21H25ClN2O4/c22-19-8-6-18(7-9-19)21(17-4-2-1-3-5-17)23-10-12-24(27,13-11-23)14-15-28-16-20(25)26/h1-9,21,27H,10-16H2/p+1/t21-/m1/s1