Ring-closing metathesis process for the preparation of macrocyclic peptides

Abstract

Disclosed is a process for preparing a compound of formula (I) by protecting the secondary amide nitrogen atom in the compound of formula (III) to obtain (IV) wherein PGis a suitable nitrogen protecting group, ring-closing the compound of formula (IV) by cyclizing it in the presence of a suitable catalyst in a suitable organic solvent to obtain (V), and then deprotecting the resulting compound of formula (V) to obtain (I), as outlined in the following scheme. The compounds of formula (I) are active agents for the treatment of hepatitis C viral (HCV) infections or are intermediates useful for the preparation of anti-HCV agents.