天然丰度的N-磷酰化氨基酸的~(15)N NMR 研究

摘要

采用~(15)N-~1H的2D HSQC、 HMBC实验方法, 测定了天然丰度的N-磷酰化氨基酸样品在溶液中的~(15)N化学位移δ_N及偶合常数J_(N-P), J_(N-H). 实验表明: 对于~(15)N天然丰度样品, 这是一种快速有效的实验方法. 研究发现: N-磷酰化后的氨基酸, 其δ_N以及与氮原子直接相连的质子~1H的化学位移均发生十分明显的高场位移, 而偶合常数~1J_(N-P), ~1J_(N-H)的变化与化合物构型相关联 .%Natural abundance N-phosphoryl amino acids were studied by ~(15)N NMR spectroscopy. ~(15)N NMR chemical shifts and coupling constants were determined by ~(15)N-~1H heteronuclear HSQC and HMBC techniques. The stereosensitive ~1J (~(15)N-~(31)P) and ~1J (~(15)N-~1H) coupling constants were used to analyze the geometry of nitrogen atoms in these compounds. The structural and ~(15)N NMR spectroscopic characteristics of N-phosphoryl amino acids were discussed.