InChI=1S/C16H21BrN2O4/c1-4-19-10(5-8-13(19)20)9-18-16(21)14-12(22-2)7-6-11(17)15(14)23-3/h6-7,10H,4-5,8-9H2,1-3H3,(H,18,21)/t10-/m0/s1