3-[2-(3-Phenyl-2-oxo-1,2-di­hydro­quin­oxalin-1-yl)eth­yl]-1,3-oxazolidin-2-one

The di­hydro­quinoxaline ring system of the title mol­ecule, C₁₉H₁₇N₃O₃, is approximately planar [maximum deviation = 0.050 (2) Å], the dihedral angle between the planes through the two fused rings being 4.75 (8)°. The mean plane through the fused-ring system forms a dihedral angle of 30.72 (5)° with the attached phenyl ring. The mol­ecular conformation is enforced by C—H...O hydrogen bonds. In the crystal, mol­ecules are linked by weak C—H...O hydrogen bonds, forming a three-dimensional network.