[1-(3-Nitro-phen-yl)-2,3-dihydro-1H-naphtho[1,2-e][1,3]oxazin-3-ylidine]malonaldehyde

The oxazine ring in the title compound, C(21)H(14)N(2)O(5), adopts a flattened boat conformation. The nitro-phenyl ring and the naphthalene ring system enclose a dihedral angle of 89.2 (1)°. An intra-molecular hydrogen bond is formed between the NH group and one of the adjacent carbonyl O atoms. In addition, the NH group forms an inter-molecular hydrogen bond to a symmetry equivalent of this carbonyl O atom, connecting the mol-ecules into centrosymmetric dimers. The structure also contains C-H⋯O inter-molecular inter-actions.