液相色譜法測定非天然氨基酸的光學(xué)純度

   以（1- 氟-2,4-二硝基苯基）-5-L-纈氨 酰胺為手性試劑、反相液相色譜法測定非天然氨基酸的光學(xué) 純度。梯度洗脫，流動(dòng)相A：含體積分?jǐn)?shù)為0.1％的三氟乙酸的乙腈，流動(dòng)相B：體積分 數(shù)為0.1％的三氟乙酸水溶液。L-和D-對映體得到良好分離。準(zhǔn)確測定了25種非天然 氨基酸L-和D-對映體的光學(xué)純度。

 
Determination of Chiral Purity of Synthetic Amino Acids by High Performance Liquid Chromatography

   after derivatization with （1- fluoro-2,4-dinitrophenyl）-5-L-valinamide （FDNP-Val-NH2）.The separation was performed with gradient elution.The phase A was acetonitrile containi ng 0.1% trifluoroacetic acid and phase B was 0.1% trifluoroacetic aci d.According to the hydrophobicity of the side chain of the amino acids,6 differe nt linear gradient programs were selected and all gradients completed in 20 minu tes.Good resolution was obtained for neutral amino acids.All L-L diastereomer o f neutral amino acids （the first letter refers to the configuration of amino aci d） were eluted faster than the D-L diastereomer with retention times less than 16 minutes.In the same gradient eluting system, the hydrophobic parameter （π value） and the position of the substituent in benzene ring of phenylalanine a lso influence the retention time of diastereomers.Usually the retention time of the phenylalanine with a large π value was longer than that with a small on e.Among the three phenylalanines containing the same