Diastereotopic fluorine substituents as 19F NMR probes of screw-sense preference in helical foldamers.
Related Articles Diastereotopic fluorine substituents as 19F NMR probes of screw-sense preference in helical foldamers.
Org Biomol Chem. 2013 May 21;11(19):3168-76
Authors: Pike SJ, De Poli M, Zawodny W, Raftery J, Webb SJ, Clayden J
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.
PMID: 23558640 [PubMed - indexed for MEDLINE]
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