In the title mol-ecule, C(21)H(24)N(2)O(4), the piperidine ring adopts a distorted boat conformation with the ethyl substituent in the axial position. The dihedral angle between the two benzene rings is 70.25 (9)°. An intra-molecular C-H⋯O inter-action is observed. In the crystal, mol-ecules are linked into a chain along the c axis by C-H⋯O hydrogen bonds and the chains are linked via weak C-H⋯π inter-actions.