Boronated L-nucleotides targeted against HIV

描述（由申请人提供）：本提案的目的是创建 一类新的抗病毒核苷酸前药，其结合了联合收割机的效力和 逆转录酶（RT）的L-核苷抑制剂的选择性 硼磷酸盐取代的优点（其中， α-磷酸被硼（BH 3）基团取代）。我们假设这些 前药将具有良好的细胞膜渗透性， 细胞内的亲脂性载体，会产生（α-P-硼烷基） 相应核苷类似物的单-、二-和三磷酸。的 提出了硼化类似物对磷酸二酯酶是稳定的， 磷酸酶，但良好的底物核苷酸激酶和选择性 病毒RT。此外，提出（α-β-硼基）三磷酸盐是 HIV-RT ATP依赖性和焦磷酸解清除的有效抑制剂 核苷酸链终止子;和一个硼磷酸键， 病毒DNA中，以显示出增加的稳定性， 导致耐药性的机制。具体目标包括：（1） 合成和表征有效病毒（α-β-硼烷基）类似物 复制抑制剂，包括以下物质的D-和L-对映体： 2 '，3'-双脱氧核苷（2 '，3'-ddN），2 '，3'-双脱氧-2 '，3'-双脱氢胸苷 (d4T)，2 '-脱氧-3'-硫代胞苷三磷酸（3 TC）和2 '，3'-二脱氧-2 '- 氟阿拉伯糖苷（2 '-FddAraN）。2)为了研究这些硼化类似物， 核苷单磷酸和二磷酸激酶的病毒底物和抑制剂 逆转录酶和哺乳动物聚合酶;以确定 结构-功能关系;选择最有效和选择性 聚合酶链终止剂用于未来的药理学研究;并研究 硼磷酸盐如何阻断病毒DNA的修复及其机制 堵塞。3)设计新的核苷酸前药， 具有适当官能团的α-β-硼化类似物， 它们的细胞渗透和靶分子的化学失活;以及 调查化学，生物化学，和生物物理特性的 对于生物化学和治疗应用最重要的类似物; 4)研究细胞对磷酸二酯酶的摄取和稳定性， 磷酸酶;并与其他实验室合作研究活性 在细胞培养中对抗人类病毒性疾病的新前药。我们预计 这些研究将有助于更好地了解 核苷活化，病毒复制和耐药性，并提供了一个 为合理设计更高效、毒性更小的抗病毒药物奠定了基础 剂.

DESCRIPTION (Provided by the applicant): The aim of this proposal is to create a new class of antiviral nucleotide prodrugs, which combine the potency and selectivity of L-nucleoside inhibitors for reverse transcriptase (RT) with advantages of boranophosphate substitution (in which an oxygen of the a-phosphate is replaced with a borano (BH3) group). We hypothesize that these prodrugs will have good cellular membrane permeability and, after hydrolysis of the lipophilic carriers inside the cell, would generate the (alpha-P-borano) mono-, di- and triphosphates of the corresponding nucleoside analogs. The boronated analogs are proposed to be stable to phosphodiesterases and phosphatases, yet good substrates for nucleotide kinases and selective for viral RTs. Moreover, the (alpha-P- borano) triphosphates are proposed to be effective inhibitors of the HIV-RT ATP-dependent and pyrophosphorolytic removal of nucleotide chain terminators; and a boranophosphate linkage incorporated into viral DNA is proposed to exhibit increased stability toward repair mechanisms that contribute to drug resistance. Our Specific Aims include 1) To synthesize and characterize (alpha-P-borano) analogs of potent viral replication inhibitors, including D- and L-enantiomers of 2',3'-dideoxynucleosides (2',3'-ddN), 2',3'-dideoxy- 2',3'-didehydrothymidine (d4T), 2'-deoxy-3'-thiacytidine triphosphate (3TC), and 2',3'-dideoxy-2'- fluoroarabinonucleosides (2'-FddAraN). 2) To study these boronated analogs as substrates and inhibitors of nucleoside mono- and diphosphate kinases, viral reverse transcriptases, and mammalian polymerases; to determine structure-function relationships; to select the most potent and selective polymerase chain terminators for future pharmacological studies; and to study how well boranophosphates block the repair of viral DNA and their mechanism of blockage. 3) To design new nucleotide prodrugs by conjugating selected alpha-P-boronated analogues with appropriate functional groups to facilitate their cell penetration and chemical inactivation of target molecules; and to investigate the chemical, biochemical, and biophysical properties of the analogs that are most essential for biochemical and therapeutic applications; 4) To investigate cell uptake and stability to phosphodiesterases and phosphatases; and to collaborate with other laboratories to study the activity of the new prodrugs against human viral diseases in cell culture. We anticipate that these studies will lead to better understanding of the mechanisms of nucleoside activation, viral replication, and drug resistance, and provide a basis for the rational design of more efficient and less toxic antiviral agents.