We have recently reported the synthesis of enantiomerically pure CF3-oxazolidine pseudoprolines (CF3-ΨPro). Complete NMR studies, together with DFT calculations, have highlighted the marked stereoelectronic effects of the CF3 group on these new proline surrogates. In this paper, we describe for the first time the conformational features of dipeptides incorporating one CF3-ΨPro residue. Extensive NMR analyses have been carried out in solution and revealed the presence of a stable type-VI β-turn in a pseudotetrapeptide sequence.
