Efficient chemical synthesis for the analogue of ubiquitin-based probe Ub–AMC with native bioactivity

Abstract

The analogue of ubiquitin-based probe ubiquitin–7-amido-4-methylcoumarin (Ub–AMC) was efficiently synthesized through a methyl thioglycolate (MTG) assisted one-pot ligation–desulfurization protocol. To obtain peptide segments with higher yield, norleucine (Nle) was used instead of methionine in the chemical synthesis procedure. Compared with native Ub–AMC, the analogue exhibits well-folded secondary structure and desired bioactivity for studying the DUB enzyme.