Abstract

A series of eleven 5-substituted-indole nucleoside residues were synthesized and incorporated into 15-mer oligodeoxynucleotide duplexes with each of the four natural bases (A, G, C, T) paired with the non-natural residues. The universal base properties of these residues were evaluated by comparing the stabilities of these complexes determined by UV thermal denaturation experiments. All of the substituted indoles were more stable than an unsubstituted indole residue, and measures of electronic influences of substituents on the indole pi system correlate with stability. Several residues were more promiscuous than the previously studied 5-nitroindole residue, but the relationship between substituents and selectivity is not clear.

摘要

合成了一系列 11 个 5 取代的吲哚核苷残基，并将其掺入 15 聚体寡脱氧核苷酸双链体中，其中四种天然碱基（A、G、C、T）中的每一个都与非天然残基配对。通过比较由紫外热变性实验确定的这些复合物的稳定性，评估了这些残基的通用碱基特性。所有取代的吲哚比未取代的吲哚残基更稳定，并且取代基对吲哚π体系的电子影响的测量与稳定性相关。几个残基比先前研究的 5-硝基吲哚残基更混杂，但取代基和选择性之间的关系尚不清楚。