title: Stereospecific synthesis of conformationally constrained gamma-amino acids: new foldamer building blocks that support helical secondary structure.
abstract: A highly stereoselective synthesis of novel cyclically constrained gamma-amino acid residues is presented. The key step involves organocatalytic Michael addition of an aldehyde to 1-nitrocyclohexene. After aldehyde reduction, this approach provides optically active beta-substituted delta-nitro alcohols (96-99% ee), which can be converted to gamma-amino acid residues with a variety of substituents at the alpha position. We have used these new building blocks to prepare alpha/gamma-peptide foldamers that adopt a specific helical conformation in solution and in the solid state.
authors.affiliation: Department of Chemistry, University of Wisconsin, Madison, Wisconsin 53706, USA.
authors.forename: Li
authors.initials: L
authors.lastname: Guo
authors.forename: Yonggui
authors.initials: Y
authors.lastname: Chi
authors.forename: Aaron M
authors.initials: AM
authors.lastname: Almeida
authors.forename: Ilia A
authors.initials: IA
authors.lastname: Guzei
authors.forename: Brian K
authors.initials: BK
authors.lastname: Parker
authors.forename: Samuel H
authors.initials: SH
authors.lastname: Gellman
mesh_terms: D000447:Aldehydes / Q000737:chemistry; D000596:Amino Acids / Q000138:chemical synthesis*; D008968:Molecular Conformation; D017433:Protein Structure, Secondary; D013237:Stereoisomerism
chemical_list: D000447:Aldehydes; D000596:Amino Acids