Synthesis of DNA Templates Containing the Fifth Base, 2-Amino-6-(dimethylamino)purine, for Specific Transcription Involving Unnatural Base Pairs
作者:Ichiro Hirao、Takahiko Nojima、Tsuneo Mitsui、Shigeyuki Yokoyama
DOI:10.1246/cl.2001.914
日期:2001.9
An unnatural nucleobase, pyridin-2-one (denoted as y), can be specifically incorporated into RNA opposite 2-amino-6-(dimethylamino)purine (denoted as x) in DNA templates by T7 RNA polymerase. For the easy preparation of DNA templates containing x, protecting groups for the 2-amino group of x were examined. Although the general N2 protecting groups, such as isobutyryl and acetyl, resisted removal by the usual treatment with concentrated ammonia at 55 °C for 6 h, the N2-phenoxyacetyl group was successfully removed from the protected oligomers. This DNA synthesis would be a useful method for preparation of DNA templates toward enzymatic incorporation of unnatural nucleosides into RNA at desired positions.
一种非天然核碱基吡啶-2-酮(以 y 表示)可通过 T7 RNA 聚合酶特异性地与 DNA 模板中的 2-氨基-6-(二甲基氨基)嘌呤(以 x 表示)相对结合到 RNA 中。为了便于制备含有 x 的 DNA 模板,研究人员对 x 的 2-氨基保护基团进行了研究。虽然一般的 N2 保护基(如异丁酰基和乙酰基)在 55 ℃ 下用浓氨水处理 6 小时后不能去除,但 N2-苯氧基乙酰基却能成功地从受保护的低聚物中去除。这种 DNA 合成方法是一种有用的 DNA 模板制备方法,可用于在所需位置将非天然核苷通过酶结合到 RNA 中。