%A Ashwani K. Thakur %A Raghuvansh Kishore %O Copyright of this article belongs to Elsevier Science. %J Tetrahedron Letters %T An observation of a folded ?-Ala conformation in a model peptide: Boc-L-Pip-?-Ala-NHCH3, X-ray diffraction study %X An X-ray crystallographic characterization of a ?locally folded? conformation of a ?-Ala residue, in a short linear peptide: Boc-L-Pip-?-Ala-NHCH3, has been described. The critical ? torsion angle between the methylene groups of the ?-Ala adopts a typical gauche (g?) conformation. The urethane moiety is found in the uncommon type a. The influence of the geometrical variation of the Pip residue on ?-Ala conformation has been emphasized. %N 51 %P 9553-9556 %V 39 %D 1998 %I Elsevier Science/Academic Press %R doi:10.1016/S0040-4039(98)02122-4 %L open777