Monitoring and Optimization of Deprotection Reactions of Peptides by Direct Sampling with Fast Atom Bombardment Mass Spectrometry

Deprotection is often one of the most critical reactions in peptide chemistry. Direct monitoring of these reactions using fast atom bombardment (FAB) mass spectrometry proved a suitable method to optimize reaction conditions. The use of the micromolar reaction scale efficiently reduces the amount of fully protected peptide needed. All investigations were carried out with cyclic analogues of biologically active peptides.