Determination of the chirality of amino acid residues in the course of subtractive edman degradation of peptides

A chiral reagent, 1-fluoro-2,4-dinitro-5-l-alanine, was synthesized for the analysis of enantiomeric mixtures of amino acids after precolumn derivatization. The resulting diastereomers can be separated and quantitated by microbore RP-HPLC. These derivatives are relatively stable under the conditions used for acid hydrolysis of peptide bonds. Thus, this reagent was included in the protocol of a subtractive Edman degradation procedure of peptides to determine the sequence position of amino acid residues with concomitant identification of their chirality at a nanomolar level. © 1991.