(4) were synthesized and incorporated in oligonucleotides employing phosphoramidite chemistry. Oligonucleotides carrying compound 2 are able to form base pairs with the four canonical DNA constituents without significant structural discrimination. The nucleoside 4 was obtained from the corresponding ribonucleoside by deoxygenation. Oligonucleotides containing compound 4 showed similar base pairing
8-aza-7-deazaadenine(
吡唑并[3,4-d]
嘧啶-4-胺)N8-(2'-
脱氧核糖核苷)(2)和7-deazaguanine(
吡咯并[3,4-d]
嘧啶-合成2-
氨基-(3H)-4-一个)C8-(2'-
脱氧核糖核苷)(4),并利用亚
磷酰胺化学将其掺入寡
核苷酸中。带有化合物2的寡
核苷酸能够与四种标准DNA成分形成碱基对,而没有明显的结构区分。通过
脱氧从相应的
核糖核苷获得核苷4。包含化合物4的寡
核苷酸显示出与2'-
脱氧异鸟苷类似的碱基配对特性。