CHEMICAL SYNTHESIS OF OLIGONUCLEOTIDE ANALOGUES

寡核苷酸类似物的化学合成

• 批准号: 3748240
• 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/3748240
• 关键词: chemical conjugate; chemical synthesis; ethylene glycols; human immunodeficiency virus; nucleic acid hybridization; nucleotide analog; oligonucleotides; polyethylenes; protein structure; virus replication

The synthesis of a, b-oligodooxyribonucleotides with alternating (3'to 3')- and (5' to 5')- internucleotidic phosphodiester linkages (24 mers) complementary to a region overlapping the splice acceptor site of the second exon that encodes the HIV-1 tat gene product has been accomplished and the physicochemical properties of these analogues have been evaluated.Presumably because of the unnatural (3' to 3')- and (5' to 5')- phosphodiester linkages of a, b- oligonucleotides, these oligomers were considerably more resistant to endo- and exonucleases than unmodified b- oligonucleotides. Furthermore, a, b-oligonucleotides formed sequence specific complexes with complementary unmodified b-DNA oligomers which were as stable as those formed with b-oligodeoxynucleoside phosphorothioates but less stable than those composed of natural DNA strands under similar conditions. The stoichiometry of complexes composed of a, b-oligonucleotides and complementary b- oligodeoxyribonucleotides was determined as 1:1.a, b-Oligonucleotides formed also complexes with complementary oligoribonucleotides but with much lower affinity than with complementary b-DNA oligomers. It would appear, based on CD spectroscopy data, that a, b- oligodeoxyribonucleotides do not accomodate well the A-type helicity conferred upon hybridization with complementary RNA oligonucleotides. A greater flexibility of the a-nucleotidic residues of a, b- oligodeoxyribonucleotides may be required to bettter accommodate the A- type helicity of RNA . a-Nucleosides with nucleobases linked to the carbohydrate moieties through flexible arms are currently being synthesized in the laboratory along with novel acyclic nucleoside analogues in an effort to develop more potent antisense oligonucleotides targeted against HIV-1 mRNAs.

具有交替的（3 '- 3 '）-和（5'至5 '）-核苷酸间磷酸二酯键（24聚体） 在一个实施方案中，所述多核苷酸与与所述多核苷酸的剪接受体位点重叠的区域互补。 编码HIV-1达特基因产物的第二个外显子已经完成 这些类似物的物理化学性质已经被 估计是因为不自然的（3'到3'）-和（5'到5'）- 由于a，B-寡核苷酸的磷酸二酯键， 比未修饰的B对内切和外切核酸酶的抗性显著更高， 寡核苷酸 此外，a，b-寡核苷酸形成序列， 与互补的未修饰的b-DNA寡聚体的特异性复合物， 与用b-寡脱氧核苷形成的那些一样稳定 硫代磷酸酯，但不如天然DNA组成的那些稳定 在类似的条件下。 配合物的化学计量 由a，b-寡核苷酸和互补的B- a，b-寡核苷酸 也与互补的寡核糖核苷酸形成复合物，但与 比互补的b-DNA寡聚体低得多的亲和力。 它将 基于CD光谱数据，出现a，B- 寡脱氧核苷酸不能很好地适应A型螺旋 与互补RNA寡核苷酸杂交。 a，B-的a-核苷酸残基的更大灵活性， 可能需要寡脱氧核糖核苷酸来更好地适应A- RNA的螺旋型。 具有连接至α-核苷的核碱基的α-核苷 通过柔性臂的碳水化合物部分目前正被 沿着在实验室合成的新型无环核苷 类似物，以开发更有效的反义寡核苷酸 靶向HIV-1 mRNA。