Resin effects in solid-phase peptide synthesis. Enhanced purity of tryptophan-containing peptides through two-step cleavage of side chain protecting groups and peptide–resin linkage
Abstract
Alkylation of tryptophan residues during acidic cleavage of tert-butyl side chain protecting groups is reduced in the absence of thiol-scavenging reagents if the peptide remains attached to the solid support throughout the deprotection reaction.