Synthesis of a TMC-95A Ketomethylene Analogue by Cyclization via Intramolecular Suzuki Coupling

Abstract
A TMC-95A analogue extended at the C-terminus with NleΨ[COCH2]Gly-Ala-Ala-NH2 was synthesized via side-chain cyclization of the linear precursor by a Suzuki cross-coupling reaction in solution to analyze the effect of additional P‘ residues on the inhibitory potency against yeast proteasome.