Efficient Synthesis of α-Branched Purine-Based Acyclic Nucleosides: Scopes and Limitations of the Method
作者:Jan Frydrych、Lenka Poštová Slavětínská、Martin Dračínský、Zlatko Janeba
DOI:10.3390/molecules25184307
日期:——
An efficient route to acylated acyclic nucleosides containing a branched hemiaminal ether moiety is reported via three-component alkylation of N-heterocycle (purine nucleobase) with acetal (cyclic or acyclic, variously branched) and anhydride (preferentially acetic anhydride). The procedure employs cheap and easily available acetals, acetic anhydride, and trimethylsilyl trifluoromethanesulfonate (TMSOTf)
通过 N-杂环(嘌呤核碱基)与缩醛(环状或无环,不同支化)和酸酐(优选乙酸酐)的三组分烷基化,报道了一种获得含有支化半胺醛醚部分的酰化无环核苷的有效途径。该过程使用廉价且易于获得的缩醛、乙酸酐和三氟甲磺酸三甲基甲硅烷基酯 (TMSOTf)。多组分反应在室温下在乙腈中进行 15 分钟,并提供中等至高产率(高达 88%)的脂肪族侧链支化的各种无环核苷。该程序展示了 N-杂环和缩醛的广泛底物范围,并且在嘌呤衍生物的情况下,还具有出色的区域选择性,几乎只提供 N-9 异构体。