The design and synthesis of non-peptide ligands with affinity and selectivity for tachykinin receptors

2,4-disubstituted morpholin-3-one based ligands which show affinity for tachykinin receptors have been designed and synthesised. Variation of the side chains attached to the central template gives rise to selectivity between receptor subtypes. This selectivity is directly analogous to that exhibited by dipeptide ligands for the same receptor subtypes.