746637-52-5Relevant articles and documents
α-Methyl phenylglycines by asymmetric α-arylation of alanine and their effect on the conformational preference of helical Aib foldamers
Costil, Romain,Fernández-Nieto, Fernando,Atkinson, Rachel C.,Clayden, Jonathan
, p. 2757 - 2761 (2018)
α-Arylated alanine derivatives were made enantioselectively by migratory rearrangement of a urea derivative using (R,R)-pseudoephedrine as a chiral auxiliary. Incorporation of a single residue of the product α-methyl phenylglycine into an otherwise achiral oligomer of aminoisobutyric acid oligomer induced a preferred screw sense, detectable by a NMR reporter located at the remote terminus of the oligomer. The magnitude of the screw sense induction was greater when the chiral residue was located at the N-terminus of the foldamer, and in some cases the sense of induction was opposite to that of related α-methylated amino acids with α-substituents other than aryl.
Role of secondary structure in the asymmetric acylation reaction catalyzed by peptides based on chiral Cα-tetrasubstituted α-amino acids
Formaggio, Fernando,Barazza, Alessandra,Bertocco, Andrea,Toniolo, Claudio,Broxterman, Quirinus B.,Kaptein, Bernard,Brasola, Elena,Pengo, Paolo,Pasquato, Lucia,Scrimin, Paolo
, p. 3849 - 3856 (2007/10/03)
In a recent series of papers, Miller and co-workers were able to show that His(π-Me)-based, terminally protected peptides are potent catalysts of the asymmetric acyl transfer reaction, useful for the kinetic resolution of alcohols. In a structure-supporting solvent, one of the most active compounds, an Aib-containing tetrapeptide, is folded in a doubly intramolecularly H-bonded β-hairpin motif incorporating a type-II′ β-turn conformation. In this work, we have expanded the study of the Miller tetrapeptide by examining a set of analogues and shorter sequences (dipeptide amides), characterized by chiral Cα-tetrasubstituted α-amino acids of diverging bulkiness and optical configuration. Peptide synthesis in solution, conformational analysis by FT-IR absorption and 1H NMR techniques, and screening of catalytic activity as well have been performed. Our results confirm the close relationship between the β-hairpin 3D-structure and the catalytic activity of the peptides. A tetrapeptide analogue slightly more selective than the Miller compound has been found. However, the terminally protected, industrially more appealing, dipeptide amides are poorly effective.
