Cyclic lactam hybrid α-MSH/Agouti-related protein (AGRP) analogues with nanomolar range binding affinities at the human melanocortin receptors

A novel hybrid melanocortin pharmacophore was designed based on the topographical similarities between the pharmacophores of Agouti related protein (AGRP) an endogenous melanocortin antagonist, and α-melanocyte-stimulating hormone (α-MSH), an endogenous melanocortin agonist. When employed in two different 23-membered macrocyclic lactam peptide templates, the designed hybrid AGRP/MSH pharmacophore yielded non-competitive ligands with nanomolar range binding affinities. The topography-based pharmacophore hybridization strategy will prove useful in development of unique non-competitive melanocortin receptor modulators.

Graphical abstractDesign and synthesis of cyclic lactam hybrid α-MSH/Agouti-related protein (AGRP) analogues with high nanomolar range binding affinities at the hMC3–5R and nanomolar range partial agonist activity at the hMC1R is reported.Figure optionsDownload full-size imageDownload as PowerPoint slide