RESIN EFFECTS IN SOLID-PHASE PEPTIDE-SYNTHESIS - ENHANCED PURITY OF TRYPTOPHAN-CONTAINING PEPTIDES THROUGH 2-STEP CLEAVAGE OF SIDE-CHAIN PROTECTING GROUPS AND PEPTIDE RESIN LINKAGE

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.