A reversible protecting group for the amide bond in peptides. Use in the synthesis of ‘difficult sequences’

Abstract

N,O-Bis-Fmoc (fluoren-9-ylmethoxycarbonyl) derivatives of Nα-(2-hydroxy-4-methoxybenzyl)amino acids 5 are useful intermediates for the preparation of peptides with reversibly protected (tertiary) peptide bonds; their value in inhibiting interchain association during solid phase peptide synthesis is demonstrated.