Direct preparation of peptide thioesters using an Fmoc solid-phase method

Abstract

Aiming at the direct preparation of peptide thioesters by an Fmoc solid-phase method, we searched a new deblocking reagent, which efficiently removed Fmoc groups while keeping the thioester intact. The deblocking reagent, which contains 1-methylpyrrolidine, hexamethyleneimine and HOBt in a one to one mixture of NMP and DMSO, realized the preparation of peptide thioesters by an Fmoc solid-phase method in a yield equivalent to that obtained by a Boc solid-phase method.