Crystal and molecular structure of glycyl-L-ieucine

Abstract

The crystal structure of the title compound has been determined by direct methods from diffractometer data. Crystals are monoclinic, with Z=2 in a unit cell of dimensions: a=6.369(5), b=5.565(5), c=15.350(10)Å ,β=102.77(4)°, space group P2₁. The structure was refined by least-squares to R 0.044 for 823 observed reflections. The four protons available for hydrogen-bond formation are a three-dimensional network which stabilizes the structure. There is significant non-planarity of the peptide linkage, the torsion angle about the peptide bond being -11.4°. The nitrogen atom of the peptide group is significantly pyramidal. The molecular conformation is discussed.