CHEMICAL SYNTHESIS OF OLIGONUCLEOTIDE ANALOGUES

寡核苷酸类似物的化学合成

• 批准号: 5200796
• 负责人: S L BEAUCAGE
• 金额: --
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/5200796
• 关键词: antiviral agents; chemical synthesis; conformation; high performance liquid chromatography; human immunodeficiency virus 1; mass spectrometry; nuclear magnetic resonance spectroscopy; nucleobase; nucleotide analog; oligonucleotides; protein purification; protein structure; virus replication

alpha,beta-Oligodeoxyribonucleotides having alternating (3'to 3')-and (5'to 5')-internucleotidic phosphodiester linkages (altDNA) represent a unique class of synthetic oligonucleotide analogues achiral at phosphorus. These modified oligonucleotides exhibit superior resistance to nucleases than native beta-oligodeoxyribonucleotides, and possess the ability to form stable complexes with either complementary DNA or RNA sequences. In this context, altDNA-DNA duplexes are thermodynamically more stable than altDNA-RNA complexes and thus demonstrate the higher affinity of alt-DNA for single stranded DNA sequences than for RNA sequences. The reduced thermal stability of altDNA-RNA complexes may result from an inherent conformational incompatibility of altDNA within the A-type helical motif of the hybrids. A strategy designed at improving the affinity of altDNA for complementary RNA oligomers entails the substitution of the alpha-mononucleotides of altDNA for alpha-mononucleotides having a distinctive linker arm between the nucleobase and carbohydrate moieties. It is postulated that additional nucleobase flexibility imparted to altDNA may facilitate the formation of Watson-Crick base pairs with native RNA oligonucleotides through better alignment of complementary nucleobases and, hence, generate more stable A-type helices. To test this rationale, the chemical synthesis of nucleoside analogues having a methylene or an ethylene arm joining nucleobase and carbohydrate entities has been achieved. Improved methodologies have been developed during the course of this work to facilitate the large-scale preparation and purification of theses nucleosides. The novel nucleoside analogues have been fully characterized by NMR spectroscopy and mass spectrometry, and converted to their phosphoramidites derivatives for incorporation into oligonucleotides at selected positions according to defined internucleotidic motifs. The oligodeoxyribonucleotide analogues have been purified to homogeneity either by HPLC or PAGE. The physicochemical properties of these oligonucleotide analogues, and their affinity for complementary DNA or RNA sequences, are currently being evaluated in the laboratory.

具有交替的（3 ′至3 ′）-和 （5 '至5'）-核苷酸间磷酸二酯键（altDNA）代表一个 一类独特的非手性合成寡核苷酸类似物. 磷 这些修饰的寡核苷酸表现出上级抗性 与天然β-寡脱氧核糖核苷酸相比， 与互补DNA或RNA形成稳定复合物的能力 序列的 在这种情况下，altDNA-DNA双链体在遗传上是互补的。 比altDNA-RNA复合物更稳定，因此证明 alt-DNA对单链DNA序列的亲和力大于对RNA的亲和力 序列的 altDNA-RNA复合物的热稳定性降低， 这是由于altDNA内部固有的构象不相容性造成的。 杂种的A型螺旋基序。 一种旨在提高altDNA与互补DNA亲和力的策略 RNA寡聚体需要取代 α-单核苷酸的altDNA，其具有独特的连接臂， 核碱基和糖部分。据推测 赋予altDNA的另外的核碱基柔性可以促进 与天然RNA寡核苷酸形成沃森-克里克碱基对 通过互补核碱基的更好排列，因此， 产生更稳定的A型螺旋。为了验证这一理论，化学品 具有亚甲基或亚乙基臂的核苷类似物的合成 已经实现了连接核碱基和碳水化合物实体。 改进 在这项工作的过程中制定了各种方法， 有利于大规模制备和纯化 核苷新的核苷类似物已得到充分的表征 通过NMR光谱和质谱，并转化为它们的 用于掺入寡核苷酸的亚磷酰胺衍生物 根据定义的核苷酸间基序选择的位置。 的 寡脱氧核糖核苷酸类似物已被纯化至均一 通过HPLC或PAGE。 这些物质的物理化学性质 寡核苷酸类似物，以及它们对互补DNA或 RNA序列，目前正在实验室进行评估。