The 1,3,4-oxadiazinane ring in the title compound, C(18)H(18)N(2)O(4), is in a twisted boat conformation. The two carbonyl groups are orientated towards the same side of the mol-ecule. The dihedral angle between the planes of the benzene rings is 76.6 (3)°. Mol-ecules are sustained in the three-dimensional structure by a combination of C-H⋯O, C-H⋯π and π-π [shortest centroid-centroid distance = 3.672 (6) Å] inter-actions.