α-Amino-β-hydroxy-γ-lactam for Constraining Peptide Ser and Thr Residue Conformation

α-Amino-β-hydroxy-γ-lactam 1 is a peptide mimic in which the Ser/Thr residue ω-, ψ-, and χ-dihedral angle geometry all are constrained by the 5-membered lactam ring. Lactams 1 were made by employing N-(Fmoc)oxiranylglycine 3 as a bis-electrophile in TFE with cat. BzOH to sequentially alkylate and acylate a variety of amino acid derivatives in one pot. Solid-phase synthesis of β-hydroxy-γ-lactam 8, an analogue of the IL-1 modulator 101.10, was achieved using this method for studying Ser/Thr geometry.