InChI=1S/C19H20N2O2/c1-22-17-8-7-14(18(12-17)23-2)11-15-5-4-10-21-19(15)16-6-3-9-20-13-16/h3,6-9,11-13H,4-5,10H2,1-2H3/b15-11+