title: Stereoselective acylation of a racemic amine with C(alpha)-methyl phenylglycine-based dipeptide 5(4H)-oxazolones.
abstract: Reactions of a racemic amine with chiral, N(alpha)-acetylated, C(alpha)-methyl l-phenylglycine-based dipeptide 5(4H)-oxazolones proceed diastereoselectively to give predominantly dipeptide alkylamides comprising d-alpha-phenylethylamine. Diastereoselectivity is remarkably sensitive to solvent polarity and reaction temperature but not significantly to the nature of the C(alpha)-tetrasubstituted alpha-amino acid at position 1 of the dipeptide. The beta-turn 3D structures of the aminolysis products were established in CDCl(3) solution by FT-IR absorption and in one case in the crystal state by X-ray diffraction as well.
authors.affiliation: Institute of Biomolecular Chemistry, CNR, Department of Chemistry, University of Padova, Padova, Italy.
authors.forename: Alessandro
authors.initials: A
authors.lastname: Moretto
authors.forename: Cristina
authors.initials: C
authors.lastname: Peggion
authors.forename: Fernando
authors.initials: F
authors.lastname: Formaggio
authors.forename: Marco
authors.initials: M
authors.lastname: Crisma
authors.forename: Bernard
authors.initials: B
authors.lastname: Kaptein
authors.forename: Quirinus B
authors.initials: QB
authors.lastname: Broxterman
authors.forename: Claudio
authors.initials: C
authors.lastname: Toniolo
mesh_terms: D000215:Acylation; D000598:Amino Acids, Cyclic / Q000737:chemistry*; D018360:Crystallography, X-Ray; D004151:Dipeptides / Q000138:chemical synthesis / Q000737:chemistry*; D005998:Glycine / Q000031:analogs & derivatives* / Q000737:chemistry; D010081:Oxazolone / Q000737:chemistry*; D011487:Protein Conformation; D017550:Spectroscopy, Fourier Transform Infrared; D013237:Stereoisomerism; D014961:X-Ray Diffraction
chemical_list: D000598:Amino Acids, Cyclic; D004151:Dipeptides; D010081:Oxazolone; C033393:methyl phenylglycine; D005998:Glycine