A comparative study of the hydrolysis pathways of substituted aryl phosphoramidate versus aryl thiophosphoramidate derivatives of stavudine
作者:T.K. Venkatachalam、G. Yu、P. Samuel、S. Qazi、S. Pendergrass、F.M. Uckun
DOI:10.1016/j.ejmech.2004.04.002
日期:2004.8
identified the hydrolysis product of the phosphoramidate derivatives and were able to show in in vitro studies that porcine liver esterase can hydrolyze the methyl ester portion of the phosphoramidate derivatives. Aryl phosphoramidate derivatives of d4T were 1000-fold more active than the corresponding aryl thiophosphoramidate derivatives, indicating that the energy of activation of hydrolysis of these phosphoramidate
进行了2',3'-didehydro-2',3'-dideoxythymidine(d4T)的氨基磷酸氨基酯和硫代氨基磷酸芳基酯衍生物的比较研究。研究集中于取代基的性质以及硫代氨基磷酸酯对这些衍生物结构的影响。这两种类型的d4T衍生物的碱水解速率表明,用硫替代氧会使水解速率降低两倍。另外,硫类似物的活化能(E(a))相对高于氧类似物的活化能。值得注意的是,在d4T的硫类似物的水解反应中形成了在氧类似物情况下不存在的中间体,并且基于LC /质谱数据提出了该中间体的暂定结构。使用HPLC和(31)P-NMR技术,我们鉴定了氨基磷酸酯衍生物的水解产物,并且能够在体外研究中显示猪肝酯酶可以水解氨基磷酸酯衍生物的甲酯部分。d4T的芳基氨基磷酸酯衍生物的活性是相应的芳基硫代氨基磷酸酯衍生物的1000倍,这表明这些氨基磷酸酯衍生物水解的活化能在其生物学效能中起着重要作用。