5-Acetyl-2-amino-6-methyl-4-(3-nitrophenyl)-4H-pyran-3-carbonitrile and 2-amino-5-ethoxycarbonyl-6-methyl-4-(3-nitrophenyl)-4H-pyrano-3-carbonitrile.

The structures of the title compounds, C15H13N3O4, (I), and C16H15N3O5 [IUPAC name: ethyl 6-amino-5-cyano-2-methyl-4-(3-nitrophenyl)-4H-pyrano-3-carboxylate], (II), are very similar, with the heterocyclic rings adopting boat conformations. The pseudo-axial m-nitrophenyl substituents are rotated by 84.0 (1) and 98.7 (1) degrees in (I) and (II), respectively, with respect to the four coplanar atoms of the boat. The dihedral angles between the phenyl rings and nitro groups are 12.1 (2) and 8.4 (2) degrees in (I) and (II), respectively. The two compounds have similar patterns of intermolecular N-H...O and N-H...N hydrogen bonding, which link molecules into infinite tapes along b.