<i>rac</i>-Methyl 4-azido-3-hydroxy-3-(2-nitrophenyl)butanoate

In the title compound, C₁₁H₁₂N₄O₅, the mean plane through the nitro substituent on the benzene ring is inclined to the benzene mean plane by 85.8 (2)°, which avoids steric interactions with the <i>ortho</i> substituents. The hydroxy group is involved in bifurcated hydrogen bonds. The first is an intramolecular O-H···O hydrogen bond, involving the ester carbonyl O atom, which gives rise to the formation of a boat-like hydrogen-bonded chelate ring. The second is an intermolecular O-H···N hydrogen bond involving the first N atom of the azide group of a symmetry-related molecule. In the crystal structure this leads to the formation of a polmer chain extending in the c-axis direction.