A. Wakahara, M. Kido, T. Fujiwara
Aug 1, 1973
Citations
0
Influential Citations
8
Citations
Journal
Bulletin of the Chemical Society of Japan
Abstract
5-Hydroxy-DL-tryptophan was crystallized from a methanol solution in the monoclinic space group C2/c, with cell-dimensions of a=16.765, b=5.892, c=20.887 A, and β=92.06°. The molecular structure and stereoconfiguration have been elucidated by the direct method for non-primitive space group. A Fourier map, calculated with the largest 198 normalized structure factors as Fourier coefficients, revealed the whole structure which was refined by the least-squares method. The molecule is a zwitterion as in the crystal structure of amino acids, each amino nitrogen atom having an extra proton. The indole ring plane forms a dihedral angle of 40° with that formed by an acid group. With respect to the conformation about the C(α)–C(β) bond, the orientation of C(β)–C(γ) bond is trans with respect to the C(α)–COO–. The molecules are arranged in double layers parallel to the ab-plane. The layer by polar groups is held together by a series of hydrogen bonds in a three-dimensional network, and by non-polar groups in the oth...