USE OF CHIRAL MONOHALO-S-TRIAZINE REAGENTS FOR THE LIQUID-CHROMATOGRAPHIC RESOLUTION OF DL-AMINO ACIDS

Nucleophilic replacement of one halogen atom (chlorine, fluorine) in the trihalo-s-triazines (2,4,6-trihalo-1,3,5-triazines), cyanuric chloride or cyanuric fluoride by reaction with either methanol, 2-naphthol, 1-methoxynaphthalene, or 4-aminoazobenzene furnished ultraviolet-absorbing, fluorescent of chromogenic dihalo-s-triazines. Substitution of a further halogen atom in these compounds by reaction with L-alanine amide provided chiral monohalo-s-triazines. The remaining halogen atom was substituted by reaction with selected D- or L-amino acids to form diastereomeric derivatives which were separated by reverse-phase (C18) high-performance liquid chromatography using mixtures of water, acetonitrile and trifluoroacetic acid as eluents. Because of its possibilities for selection among a large number of detection groups in combination with various chiral moieties, the approach is considered to be a general method for the design and construction of tailor-made reagents suitable for precolumn derivatization and indirect liquid chromatographic separation of amino acid enantiomers.