The title compound, C21H19NO4, (II), is an acridine derivative with an angl
e of 68.30 (2)degrees between the aromatic ring system and the ethylene moi
ety. It is remarkable that (II) is isostructural with diethyl 2-(anthracen-
9-ylmethylene)malonate, which bears a C atom at the position where in (II)
an N atom is found.