The title compound, C23H29N3O4, has potential calcium modulatory properties. The conformation of the 1,4-dihydropyridine ring is unusual in that it is planar, instead of the usual shallow boat. The 3-nitrophenyl substituent is in the synperiplanar orientation with respect to the dihydropyridine ring plane. The oxocyclohexene ring has a distorted envelope conformation, with the out-of-plane atom being disordered on opposite sides of the ring plane. The molecules are linked into chains by intermolecular hydrogen bonds.