Enantioselective synthesis of (2S)-2-(4-phosphonophenylmethyl)-3-aminopropanoic acid suitably protected for peptide synthesis

Protected d-β-2-(4-phosphono) phenylalanine was prepared by a multistep synthesis, involving the diastereoselective alkylation of a chiral enolate. This new compound can be further incorporated into peptidic backbone by means of solid-phase peptide synthesis in order to synthesize short peptides adopting β-turn or α-helix conformations.