title: Conformational study of alanine and alpha-aminoisobutyric psi [NHCO]-retroamide peptide analogues.
abstract: The minimum-energy conformations of N,N'-dimethyl-2-methylmalondiamide (2mMA) and N,N'-dimethyl-2-dimethylmalondiamide (2dmMA) have been computed using the AM1 method. The results show that molecules tend to form an intramolecular six-membered ring hydrogen-bond system. The same trend is observed in crystals of malonamide derivatives substituted in the central carbon atom. The results are also compared with previous molecular-mechanics calculations. The conformational trends of 2mMA and 2dmMA are very similar to those showed by N,N'-dimethylmalondiamide. Details of the computed conformational energy maps for 2mMA and 2dmMA compounds are given.
authors.affiliation: Department of Chemical Engineering, Technical College for Industrial Engineers, Polytechnic University of Catalunya, Barcelona, Spain.
authors.forename: C
authors.initials: C
authors.lastname: Alemán
authors.forename: J J
authors.initials: JJ
authors.lastname: Perez
mesh_terms: D000409:Alanine / Q000737:chemistry*; D000621:Aminoisobutyric Acids / Q000737:chemistry*; D008764:Methylmalonic Acid / Q000031:analogs & derivatives* / Q000737:chemistry; D010455:Peptides / Q000737:chemistry*; D011487:Protein Conformation; D013329:Structure-Activity Relationship; D013816:Thermodynamics
chemical_list: D000621:Aminoisobutyric Acids; D010455:Peptides; C087824:N,N'-dimethyl-2-methylmalondiamide; C087825:N,N'-dimethyl-2-dimethylmalondiamide; C100049:2-aminoisobutyric acid; D008764:Methylmalonic Acid; D000409:Alanine