title: Crystal structures of heterochiral peptides. Part II. tert-Boc-valyl-D-alanyl-leucyl-alanyl methoxide.
abstract: Crystal structure of a heterochiral peptide, viz. Boc-Val1-D-Ala2-Leu3-Ala4-OMe with a D chiral residue in the second position of a sequence, has been determined [a = 40.44(1), b = 4.887(5), c = 15.381(5) A, beta = 109.6(1)degrees, space group C2, Z = 4, R = 0.11]. The peptide is in a parallel beta-sheet structure terminated by a distinct local bend. The structure is established by N-H...O as well as C alpha-H...O hydrogen bonds. The contiguous C alpha-H...O hydrogen bond observed in this structure is an unique observation.
authors.affiliation: Department of Crystallography and Biophysics, University of Madras, India.
authors.forename: V
authors.initials: V
authors.lastname: Nagarajan
authors.forename: V
authors.initials: V
authors.lastname: Pattabhi
authors.forename: A
authors.initials: A
authors.lastname: Johnson
authors.forename: V
authors.initials: V
authors.lastname: Bobde
authors.forename: S
authors.initials: S
authors.lastname: Durani
mesh_terms: D002942:Circular Dichroism; D006860:Hydrogen Bonding; D009682:Magnetic Resonance Spectroscopy; D010455:Peptides / Q000737:chemistry*; D011487:Protein Conformation
chemical_list: D010455:Peptides