The title compound, C(19)H(16)N(4)O(2), has an almost planar fused N-heterocyclic system (r.m.s. deviation = 0.031 Å) and an almost planar five-membered 1,3-oxazolidine ring (r.m.s. deviation = 0.015 Å) at the ends of an ethyl-ene chain [N-C-C-N torsion angle = -65.6 (2)°]. The ring systems are inclined at 38.1 (1)° to one another.