InChI=1S/C15H18N4O/c20-15(14-11-3-1-2-4-12(11)17-18-14)16-13-9-19-7-5-10(13)6-8-19/h1-4,10,13H,5-9H2,(H,16,20)(H,17,18)/t13-/m1/s1