A High Yield Synthesis of Phosphatidyl Ethanolamines Using Phosphoramidite Intermediates
作者:Christopher Mcguigan、Bernadette Swords
DOI:10.1055/s-1993-25816
日期:——
Alkyl 2-aminoethyl hydrogen phosphates (phosphatidyl ethanolamines) were prepared via phosphoramidite chemistry. tert-Butoxy-carbonyl N-protection of 2-aminoethanol, followed by cyclisation with phosphorus(III) chloride gave the phosphoramidite 3-tert-butoxycarbonyl-2-chloro-1,3, 2-oxazaphospholidine (3). This reacted with long chain alcohols (C6 to C18) to give 2-alkyloxy-3-tert-butoxycarbonyl-1,3,2-oxazaphospholidines 4a-d which were oxidised to 2-alkyloxy-3-tert-butoxycarbonyl-2-oxo-1,3, 2-oxazaphospholidines 5a-d with dinitrogen tetroxide. Simultaneous heterocycle cleavage and N-deprotection were achieved with refluxing aqueous tetrahydrofuran, to give the target 2-aminoethyl phosphates 6a-d. The reaction conditions are mild, and the yields are almost quantitative in terms of the long chain alcohol. The products and intermediates are fully characterised by a range of spectroscopic and analytical methods.
烷基2-氨基乙基磷酸酯(磷脂酰乙醇胺)是通过膦酰胺化学制备的。首先用叔丁氧羰基保护2-氨基乙醇,再用三氯化磷进行环化反应得到膦酰胺3-叔丁氧羰基-2-氯-1,3,2-氧杂膦杂环己烷(3)。然后与长链醇(C6至C18)反应,生成2-烷氧基-3-叔丁氧羰基-1,3,2-氧杂膦杂环己烷4a-d,再用四氧化二氮氧化为2-烷氧基-3-叔丁氧羰基-2-氧代-1,3,2-氧杂膦杂环己烷5a-d。通过回流水合四氢呋喃实现杂环的裂解和N-脱保护,得到目标产物2-氨基乙基磷酸酯6a-d。反应条件温和,长链醇的产率几乎定量。产物和中间体均通过一系列光谱和分析方法得到了充分表征。