InChI=1S/C20H21N3O4/c1-11(2)16-9-15(5-6-17(16)24)27-19-12(3)7-14(8-13(19)4)23-20(26)22-18(25)10-21-23/h5-11,24H,1-4H3,(H,22,25,26)