Racemisation of activated, urethane-protected amino-acids by p-dimethyl-aminopyridine. Significance in solid-phase peptide synthesis

Abstract
Racemisation of -t-butoxycarbonyl, fluoren-9-ylmethoxycarbonyl, and benzyloxycarbonyl amino-acid anhydrides by p-dimethylaminopyridine is shown to ba a significant side reaction during attachment of the first amino-acid to the resin in solid-phase peptide synthesis.