The central β-lactam ring of the title compound, C(23)H(21)NO(3), is almost planar (r.m.s. deviation = 0.032Å). The meth-oxy-benzene ring is almost coplanar with the β-lactam ring [dihedral angle = 1.87 (11)°], whereas the tolyl ring is almost normal to it [75.73 (12)°]. The dihedral angle between the β-lactam ring and the O-bonded phenyl ring is 51.95 (12)°. An intra-molecular C-H⋯O inter-action generates an S(6) ring. The crystal structure features inter-molecular C-H⋯O hydrogen bonds, forming layers parallel to (011), and weak C-H⋯π inter-actions. Two aromatic π-π stacking inter-actions [centroid-centroid distances = 3.6744 (12) and 3.6799 (11) Å] are also observed.