Synthesis and Conformational Analysis of α,β‐Difluoro‐γ‐amino Acid Derivatives

Shape control: Synthetic access has been achieved to all possible stereoisomers of the α,β-difluoro-γ-amino acid motif. These novel building blocks can readily be coupled to other amino acids, and the resulting peptides display unique conformational behavior depending on the fluorine stereochemistry. The differences in peptide conformation can be rationalized in terms of the various stereoelectronic effects associated with CF bonds.