Pätzold Ralf, Theis Christoph, Brückner Hans
Interdisciplinary Research Center, Institute of Nutritional Science, Department of Food Sciences, Giessen, Germany.
Chirality. 2006 Aug;18(7):551-7. doi: 10.1002/chir.20290.
Synthetic dipeptides comprising mixtures of enantiomers, diastereomers, or sequential isomers were converted into their N-perfluoroacetyl dipeptide esters (perfluoroacetyl: trifluoroacetyl, pentafluoroacetyl, heptafluorobutyryl; ester: methyl, 1-propyl, 2-propyl, 2,2,2-trifluoroethyl) and analyzed by GC-MS on the chiral stationary phases Chirasil-L-Val and Lipodex-E using helium as carrier gas. Further, dipeptides were converted into their N-trifluoroacetyl dipeptide S-(+)-2-butyl esters and separated on achiral phenylmethyl polysiloxane column (HP-5 MS). Derivatization of dipeptides was performed at ambient temperature in order to avoid formation of the corresponding diketopiperazines. The best separation of stereoisomers was achieved with TFA and PFP methyl esters on Chirasil-L-Val.
将包含对映体、非对映体或顺序异构体混合物的合成二肽转化为它们的 N-全氟乙酰基二肽酯（全氟乙酰基：三氟乙酰基、五氟乙酰基、七氟丁酰基；酯：甲基、1-丙基、2-丙基、2,2,2-三氟乙基），并使用氦气作为载气在手性固定相 Chirasil-L-Val 和 Lipodex-E 上通过气相色谱-质谱联用仪进行分析。此外，将二肽转化为它们的 N-三氟乙酰基二肽 S-(+)-2-丁酯，并在手性苯基甲基聚硅氧烷柱（HP-5 MS）上进行分离。为避免形成相应的二酮哌嗪，二肽的衍生化反应在室温下进行。使用三氟乙酸（TFA）和五氟丙酸（PFP）甲酯在 Chirasil-L-Val 上实现了立体异构体的最佳分离。
