Crystal structure of γ-ethyl-L-glutamate N-carboxy anhydride

In the title compound (alternative name N-carboxy-L-glutamic anhydride γ-ethyl ester), C₈H₁₁NO₅, the oxazolidine ring is essentially planar, with a maximum deviation of 0.019 (2) Å. In the crystal, molecules are linked by N - H⋯O hydrogen bonds between the imino group and the carbonyl O atom in the ethyl ester group, forming a tape structure along the c-axis direction. The oxazolidine rings of adjacent tapes are arranged into a layer parallel to the ac plane. This arrangement is favourable for the polymerization of the title compound in the solid state.