New family of base- and nucleophile-sensitive amino-protecting groups. A Michael-acceptor-based deblocking process. Practical utilization of the 1,1-dioxobenzo(b)thiophene-2-ylmethyloxycarbonyl (Bsmoc) group

The base-sensitive amino-protecting groups such as Fmoc, react to facile beta-elimination processes. Attempts to apply Fmoc protection to an inverse Merrifield peptide segment synthesis were disappointing and the search for a different type fo amino-protecting group was undertaken. The desired result was achieved by appropriate positioning of a urethane function relative to a Michael acceptor.