title: Diastereotopic fluorine substituents as 19F NMR probes of screw-sense preference in helical foldamers.
abstract: Ligating simple amino alcohol or amino ester monomers containing enantiotopic fluorine substituents to the C-terminus of a helical peptide places the fluorine atoms in diastereotopic environments, and gives two distinct and easily identifiable signals in the (19)F NMR spectrum. In the case of a dynamically inverting helix built from achiral monomers, the chemical shift separation between the (19)F signals provides a simple means of analysing the ratio of screw-sense conformers in the oligomer, in cases where an asymmetric bias leads to a screw-sense preference.
authors.affiliation: School of Chemistry, University of Manchester, Oxford Rd., Manchester M13 9PL, UK.
authors.forename: Sarah J
authors.initials: SJ
authors.lastname: Pike
authors.forename: Matteo
authors.initials: M
authors.lastname: De Poli
authors.forename: Wojciech
authors.initials: W
authors.lastname: Zawodny
authors.forename: James
authors.initials: J
authors.lastname: Raftery
authors.forename: Simon J
authors.initials: SJ
authors.lastname: Webb
authors.forename: Jonathan
authors.initials: J
authors.lastname: Clayden
mesh_terms: D018360:Crystallography, X-Ray; D005456:Fluorescent Dyes / Q000138:chemical synthesis / Q000737:chemistry*; D005461:Fluorine / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D008958:Models, Molecular; D015394:Molecular Structure; D010455:Peptides / Q000737:chemistry*; D017510:Protein Folding; D013237:Stereoisomerism
chemical_list: D005456:Fluorescent Dyes; D010455:Peptides; D005461:Fluorine