SYNTHESIS OF SPECIFICALLY MODIFIED OLIGONUCLEOTIDES

该项目的长期目标是开发和展示 15 N的合成和利用所需的合成策略 标记的核酸。 氮-15标记的寡核苷酸，核糖或 脱氧核糖，将是非常宝贵的探针核酸结构，药物， 结合和蛋白质-核酸相互作用。 事实上， 这些类型的信息只能从这样的15 N探针获得。 此外，虽然现代高场NMR光谱仪已经有了一些 时间的必要能力，15 N标记的寡核苷酸需要 都无法联系上 这些15 N标记的 寡核苷酸不能开始实现，直到实际的路线， 都有。 拟制定的方法和程序将 对15 N标记的寡核苷酸的可用性有重大影响， 使其首次得到广泛应用。 此外该 制备标记的寡核苷酸并通过15 NNMR分析， 提供有关DNA结构、药物结合和 蛋白质-DNA相互作用 这项研究的第一阶段将是开发15 N的路线， 标记的嘌呤脱氧核苷，特别是15 N标记的06- 甲基脱氧鸟苷 15 N将在每个位置有选择地引入 除了糖苷氮之外的氮。 的每个15 N导数 脱氧腺苷、脱氧鸟苷和O 6-甲基脱氧鸟苷将被 制备 此外，2-氨基嘌呤，2，6-二氨基嘌呤， 次黄嘌呤和O 6-甲基次黄嘌呤脱氧核苷也将 建议的路线。 为了使这些15 N标记 化合物通常可获得，合成路线将被设计为 尽可能经济。 第二阶段将是这些15 N标记的 将脱氧核苷转化为寡核苷酸。 大规模H-膦酸盐 方法，其中标记的脱氧核苷的有效利用是 将被用于寡核苷酸合成。 这些 程序将适用于任何寡核苷酸合成， 规模和经济是重要的。 最后阶段将是 研究，通过15 N核磁共振，碱基配对的O 6 MeG，碱基配对的 错配，新的DNA结构，其中可能包括Hoogsteen配对， 7-位，药物-DNA相互作用，其可以通过[3- 15 N]和[2- 15 N]在小沟，和蛋白质-DNA相互作用， 可以通过大沟中的[7- 15 N]进行监测。

The long-term goals of this project are to develop and demonstrate the synthetic strategies necessary for the synthesis and utilization of 15N labeled nucleic acids. Nitrogen-15 labeled oligonucleotides, ribo or deoxyribo, will be invaluable probes of nucleic acid structure, drug- binding, and protein-nucleic acid interaction. In fact, there are some types of information which may be available only from such 15N probes. Moreover, although modern high-field nmr spectrometers have had for some time the necessary capabilities, the 15N labeled oligonucleotides needed have been unavailable. The potential of these 15N labeled oligonucleotides cannot begin to be realized until practical routes to them are available. The methods and procedures to be developed will have a major impact on the availability of 15N labeled oligonucleotides, allowing them to be widely used for the first time. In addition, the labeled oligonucleotides to be prepared and analyzed by 15N nmr will provide important information about DNA structure, drug-binding, and protein-DNA interactions. The first phase of this research will be to develop routes of 15N labeled purine deoxynucleosides, in particular to 15N labeled 06- methyldeoxyguanosine. The 15 N is to be introduced selectively at each nitrogen except the glycosidic nitrogen. Each of the 15N derivatives of deoxyadenosine, deoxyguanosine, and O6-methyldeoxyguanosine will be prepared. Furthermore, the 2-aminopurine, 2,6-diaminopurine, hypoxanthine and O6-methylhypoxanthine deoxyribosides also will be available by the routes proposed. In order to make these 15N labeled compounds generally available, the synthetic routes will be designed to be as economical as possible. The second phase will be incorporation of these 15N labeled deoxynucleosides into oligonucleotides. A large-scale H-phosphonate method, in which efficient use of the labeled deoxynucleosides is emphasized, will be used for the oligonucleotide synthesis. These procedures would be applicable to any oligonucleotide synthesis in which scale and economy are important. The final phase will be to investigate, by 15N nmr, the base pairing of O6MeG, base pairing of mismatches, novel DNA structures which may include Hoogsteen pairing at the 7-position, drug-DNA interactions which may be monitored by the [3- 15N] and [2-15N] in the minor groove, and protein-DNA interactions which may be monitored by the [7-15N] in the major groove.