Efficient incorporation of 1-(2-deoxy-β-d-ribofuranosyl)-2-oxo-imidazole-4-carboxamide into DNA via a suitable convertible phosphoramidite derivative
作者:Claudio Cadena-Amaro、Sylvie Pochet
DOI:10.1016/j.tet.2005.03.040
日期:2005.5
The synthetic scheme of 1-(2-deoxy-β-d-ribofuranosyl)-2-oxo-imidazole-4-carboxamide (3) is based on the ring contraction of pyrimidine (5-BrdU) into imidazolin-2-one. The rearrangement leads to the unexpected mixture of the deoxynucleoside 4β and its α anomer. The mechanism of the anomerisation under basic conditions is proposed. Further conversion of 4-carboxylic acid into amide affords the title
1-(2-脱氧-β-d-呋喃核糖基)-2-氧代-咪唑-4-羧酰胺(3)的合成方案基于嘧啶(5-BrdU)到咪唑啉-2-酮的环收缩。重排导致脱氧核苷4β和其α端基异构体的意外混合物。提出了在基本条件下的异构化机理。4-羧酸进一步转化成酰胺,得到标题化合物3。为了制备适合于将修饰的核碱基化学掺入DNA中的亚磷酰胺衍生物11,优选将4-羧酸转化成乙酯。热变性研究表明,与嘧啶相比,所用序列内的2-oxoY与嘌呤的配对更有利。