title: Conformational properties of N-acetyl-L-alanine N',N'-dimethylamide.
abstract: Ab initio/DFT analysis of the conformational properties of free Ac-Ala-NMe(2) (N-acetyl-L-alanine-N',N'-dimethylamide) in terms of the N-H.O, N-H.N, C-H.O hydrogen bonds and C(delta+) = O(delta-) dipole attractions was performed. The Ala residue combined with the C-terminal tertiary amide prefers an extended conformation and that characteristic of the (i + 1)th position of the betaVIb turn. These can be easily remodelled into a structure compatible with the (i + 1)th position of the betaII/betaVIa turn. The residue has also the potential to adopt the conformation accommodated at both central positions of the betaIII/betaIII' turn or the (i + 1)th position of the betaI/beta'I turn.
authors.affiliation: Institute of Chemistry, University of Opole, Opole, Poland.
authors.forename: Dawid
authors.initials: D
authors.lastname: Siodłak
authors.forename: Barbara
authors.initials: B
authors.lastname: Rzeszotarska
authors.forename: Małgorzata A
authors.initials: MA
authors.lastname: Broda
mesh_terms: D000409:Alanine / Q000031:analogs & derivatives* / Q000737:chemistry; D000478:Alkylation; D000577:Amides / Q000737:chemistry*; D002151:Calorimetry; D008958:Models, Molecular; D008968:Molecular Conformation; D010455:Peptides / Q000737:chemistry / Q000494:pharmacology; D011487:Protein Conformation; D013816:Thermodynamics
chemical_list: D000577:Amides; D010455:Peptides; C010530:N-acetylalanine; D000409:Alanine