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One-step conversion of amino acids into N-menthyloxycarbonyl alkyl ester derivatives for chiral gas chromatography.

Amino acids dissolved in aqueous methanol (or ethanol) and treated with optically active menthyl chloroformate were converted into N-menthyloxycarbonyl methyl (or ethyl) ester derivatives within a few minutes at room temperature. The obtained diastereomeric derivatives, with the exception of arginine and histidine, had suitable gas chromatographic properties allowing enantiomeric analysis of a large number of proteinogenic and synthetic amino acids.