InChI=1S/C15H20N2O3/c1-9(2)7-12-14(19)17-13(15(20)16-12)8-10-3-5-11(18)6-4-10/h3-6,9,12-13,18H,7-8H2,1-2H3,(H,16,20)(H,17,19)/t12-,13+/m0/s1