InChI=1S/C18H18N2O3/c21-17-8-14-15(20-17)6-7-16-18(14)23-13(11-22-16)10-19-9-12-4-2-1-3-5-12/h1-7,13,19H,8-11H2,(H,20,21)/t13-/m0/s1