五氯化磷辅助下氨基酸的自组装成肽反应研究

Studies on the Self-assembly of Amino Acids into Peptides Mediated by Phosphorus Pentachloride

L α 氨基酸和D α 氨基酸可与五氯化磷直接发生磷酰化反应 ,随后自组装成多肽 ,但 β 氨基酸不能成肽 ,DL α 氨基酸成肽困难 ;在SOCl2 存在下 ,α 氨基酸也不能成肽 .用电喷雾质谱研究了氨基酸的自组装反应 .反应过程中有五元环状的氨基酸五配位磷中间体生成 ,使用硅烷基保护的氨基酸 ,在 3 1PNMR中可观察到五配位磷中间体 .

L-α-Amino acids and D-α-amino acids, mediated by phosphorus pentachloride, could take place the phosphorylation and then assembled into polypeptides. However, β-amino acids could not assemble into polypeptides, and the self-assembly of DL-α-amino acids into peptides were difficult. α-Amino acids could not assemble into peptides mediated by thionyl chloride. The self-assembly reactions were studied by positive ion electrospray ionization mass spectrometry, and the five-membered cyclic penta-coordinated phosphoryl amino acid intermediates were found in the course of self-assembly into peptides. The intermediates could be trapped by 31P NMR spectroscopy after amino acids were trimethylsilylized to N,O-bis(trimethylsilyl)amino acids.