Synthesis of sidechain adapted β-turn mimics for modifying the C-terminus of substance P

Sidechain adapted β-turn mimics of type 1 characterised by a fixed cis-conformation of the peptide chain in the aminopiperidinonecarboxylate scaffold have been synthesised from pyrazinones in order to perform a β-turn scan of the messenger region of substance P. The synthesis of a substance P peptide analogue is also described.