Dimethyl 2-[(acridin-9-yl)methylidene]malonate

In the title compound, C19H15NO4, the acridine system is essentially planar (r.m.s. deviation = 0.015 ). The crystal packing exhibits π–π interactions between pairs of centrosymmetric molecules, one of them between the central heterocyclic rings and others between the outer benzene rings of the acridine systems, with centroid–centroid distances of 3.692 (1) and 3.754 (1) , respectively. These pairs are further linked by additional π–π interactions along the a-axis direction through one of the two outer benzene ring of neighboring molecules, with a centroid–centroid distance of 3.642 (2) .