This invention relates to nucleoside, nucleotide, and oligonucleotide analogs that incorporate non-standard nucleobase analogs, defined to be those that present a pattern of hydrogen bonds to a paired nucleobase analog in a complementary strand that is different from the pattern presented by adenine, guanine, cytosine, and thymine. The invention is specifically concerned with nucleotide analogs that present the donor-donor-acceptor, hydrogen bonding patterns on pyrimidine analogs, and especially those that are analogs of ribonucleotides, including protected ribonucleotides suitable for phosphoramidite-based synthesis of RNA. The heterocycles on these nucleoside analogs are aminopyridones that have electron withdrawing groups attached to the position analogous to the 5-position of the ring in standard pyrimidines, including nitro, cyano, and carboxylic acid derivatives.
这项发明涉及包含非标准核碱基模拟物的核苷酸、核苷酸和寡核苷酸模拟物,这些非标准核碱基模拟物被定义为在与配对的核碱基模拟物形成的互补链中呈现出与
腺嘌呤、
鸟嘌呤、
胞嘧啶和胸腺
嘧啶的氢键模式不同的模式。该发明特别涉及呈现出供体-供体-受体、氢键模式的
嘧啶模拟物,特别是那些
核糖核苷酸模拟物,包括适用于RNA
磷酸酰胺基合成的受保护的
核糖核苷酸。这些核苷酸模拟物上的杂环是
氨基吡啶酮,其具有连接到与标准
嘧啶环中的5-位置类似的位置的电子吸引基团,包括硝基、
氰基和
羧酸衍
生物。