title: Crystal structures of a D-residue containing tetrapeptides. 1. tert-Boc-D-valyl-alanyl-leucyl-alanyl-methoxide, butanol solvate.
abstract: The crystal structure of a heterochiral peptide, viz. Boc-D-Val-Ala-Leu-Ala-OMe, with a D-residue in the beginning of the sequence has been determined (a = 9.464(5), b = 35.615(5), c = 9.703(2) A, space group P2(1)2(1)2, Z = 4, R = 0.09). The peptide is in the extended beta-conformation and the packing is stabilised by four N--H ... O hydrogen bonds in an antiparallel beta-sheet arrangement. The solvent molecule is disordered and does not have any specific interactions with the peptide.
authors.affiliation: Department of Chemistry, I.I.T. Powai, Bombay, India.
authors.forename: V
authors.initials: V
authors.lastname: Bobde
authors.forename: S
authors.initials: S
authors.lastname: Durani
authors.forename: V
authors.initials: V
authors.lastname: Pattabhi
authors.forename: C
authors.initials: C
authors.lastname: Sadasivan
mesh_terms: D000595:Amino Acid Sequence; D018360:Crystallography, X-Ray; D006860:Hydrogen Bonding; D008969:Molecular Sequence Data; D009842:Oligopeptides / Q000737:chemistry*; D017433:Protein Structure, Secondary; D012997:Solvents; D013237:Stereoisomerism
chemical_list: D009842:Oligopeptides; D012997:Solvents; C094456:tert-butoxycarbonyl-valyl-alanyl-leucyl-alanine methyl ester