(E)-3-[4-(Dimethyl-amino)-benzyl-idene]-2,3-di-hydro-1H,9H-pyrrolo-[2,1-b]quinazolin-9-one.

The title compound, C(20)H(19)N(3)O, was obtained by condensation of 2,3-dihydro-1H,9H-pyrrolo-[2,1-b]quinazolin-9-one (alkaloid de-oxy-vasicinone, isolated from Peganum Harmala) with 4-(dimethyl-amino)-benzaldehyde in the presence of sodium methoxide. The 2,3-dihydro-1H,9H-pyrrolo-[2,1-b]quinazolin-9-one part of the mol-ecule is roughly planar (r.m.s. deviation = 0.0178 Å) and is essentially coplanar with the benzil-idene ring (r.m.s. deviation = 0.0080 Å), forming a dihedral angle of 5.0 (1)°. The crystal structure is stabilized by two aromatic π-π stacking inter-actions observed between the benzene rings of neighboring mol-ecules [centroid-centroid distance = 3.7555 (19) Å.