Fluorinated Aromatic Monomers as Building Blocks To Control α‑Peptoid Conformation and Structure

Peptoids are peptidomimetics of interest in the fields of drug development and biomaterials. However, obtaining stable secondary structures is challenging, and designing these requires effective control of the peptoid tertiary amide cis/trans equilibrium. Herein, we report new fluorine-containing aromatic monomers that can control peptoid conformation. Specifically, we demonstrate that a fluoro-pyridine group can be used to circumvent the need for monomer chirality to control the cis/trans equilibrium. We also show that incorporation of a trifluoro-methyl group (N CF3 Rpe) rather than a methyl group (NRpe) at the α-carbon of a monomer gives rise to a 5-fold increase in cis-isomer preference.