N(6)-Acetyl-5,7-diphenyl-5,6,7,8-tetrahydrobenzo[b]-1,6-naphthyridine

The single-crystal X-ray diffraction study of the title mol­ecule [alternative name: N(2)-acetyl-1,3-di­phenyl-1,2,3,4-tetra­hydro­benzo­[b][1,6]naphthyridine], C26H22N2O, confirms that it is a 1,6-naphthyridine derivative whose structural characterization was not possible from 1H, 13C NMR and mass spectral data. The tetra­hydro-1,6-napthyridine ring has a boat conformation. The equatorial and axial orientations of the two phenyl groups and the coplanarity of the acetyl group with the tetra­hydro­naphthyridine ring are also confirmed.