InChI=1S/C18H25NO4/c1-11(9-13(3)18(22)23)8-12(2)16(20)10-17(21)14-4-6-15(19)7-5-14/h4-7,9,11-12,16,20H,8,10,19H2,1-3H3,(H,22,23)/b13-9+