3-tert-Butyl 5-methyl (2R,4S,5R)-2-(4-methoxyphenyl)-4-(3-nitrophenyl)-1,3-oxazolidine-3,5-dicarboxylate.

The title mol-ecule, C(23)H(26)N(2)O(8), was synthesized in three steps starting from m-nitro-cinnamic acid. The central oxazolidine ring adopts an almost perfect envelope conformation with the O atom as the flap [puckering parameter ϕ = 0.3 (6)°]. The dihedral angle formed by the benzene rings is 61.81 (9)°. In the crystal, mol-ecules are connected into double chains parallel to [010] by C-H⋯O hydrogen bonds. The absolute configuration was assigned from the synthetic procedure.