The crystal and molecular structure of L-citrulline hydrochloride

The crystal of L-citrulline hydrochloride C6H13N3O3. HCI,has been determined using three-dimensional photographic data. The crystals are monoclinic, space group C2, with cell dimensinos a=17.86, b=5.09, c=11.77 Å and β=106.8°. Refinement was carried out with full-matrix least-squares methods, including anisotopic thermal parameters foe all non-hydrogen atoms, to a final R index of 0.071 for 920 observed reflexions. The ctystal structure is stabilized by a three-dimensional network of hydrogen bonds. The backbone and side-group conformation of the citrulline molecule have been stucied. The side-group conformation is similar to that of arginine in the structure of L-arginine dihydrate