HIV RNase H Natural Product Inhibitors: Isolation and Optimization

我们的目标是确定和优化植物来源的小分子来抑制HIV RT相关的RNaseH(RNH)活性，这是HIV干预的一个新靶点。该项目的总体目标是从10,000个组分(第一个程序)的初始筛选中推荐2-3个待开发的化合物(CD)，并从筛选植物来源文库的其余部分(150,000个组分)中推荐4-6个CD(备份程序)。第一代CDS的IC50应达到50 nm或更高，而第二代CDS的IC50应为个位数nm。这些化合物应该可以有效地抑制对当前药物具有抗药性的艾滋病毒株。RNH抑制剂(RNHI)将首先使用生化和病毒学数据进行优化，然后利用从RT-RNHI复合体的X射线结晶学研究(参见本RFA中的其他项目)获得的计算和结构信息，以允许合理设计将被合成或半合成的类似物。如果采用半合成的方法，我们可以使用我们的50 L生物反应器来生产克量的起始材料，从而使我们能够生成一个小的类比物库。此外，一些分子还将采用组合合成和平行合成，以增加潜在先导的数量和化学多样性。我们将坚持已有的指导方针，如利平斯基的五项原则，以增加我们获得类药物分子的机会。显示活性提高的类似物将接受ADME/PK研究，以便选择类似药物的线索。这个过程将被重复，直到我们达到表4中描述的CD的轮廓。我们希望在我们的RNHI药物发现中包括另一种方法。我们将利用我们一些先导的代谢物的产生作为鉴定RNHI的新化学类型的来源。我们对迄今取得的结果感到非常鼓舞(Tablel)。生化和基于细胞的值之间有很强的相关性，有些患者的IC50；1uM具有出色的治疗指数&gt；200。这是在确定和发展农村卫生保健机构方面向前迈出的重要一步。这是对我们到目前为止开发的植物细胞培养技术的致敬。一个高度多样化的文库，来自2200多种植物，代表284个植物科， 这是由于次级代谢物产生的高度重复性所决定的。该项目在提供新型艾滋病毒药物方面具有巨大的潜在影响。

Our objective is to identify and optimize plant derived small molecules for the inhibition of HIV RT-associated RNase H (RNH) avtivity, a novel target for HIV intervention. The overall goal of this poject is to recommend 2-3 compounds for development (CD) from the initial screen of 10,000 fractions (1st program) and recommend 4-6 CDs (back up program) from screening the rest of the plant derived library (150,000 fractions). The first generation CDs should attain an IC50 of 50 nm or better while second generation CDs should have single digit nm IC50. These compounds should be effective in ihibiting HIV strains that are resistant to current drugs. RNH inhibitors (RNHI) will be optimized using biochemical and virologic data initially followed by utilizing computanional and structural information obtained from X-ray crystallographic studies of RT-RNHI complexes (see other projects within this RFA) to allow rational design of analogs that will be either synthesized or semi-synthesized. In case a semi-synthetic approach is adopted, we can use our 50 L bioreactor to produce gram quantities of the starting material to allow us to generate a small library of analogs. In addition, combinatorial and parallel synthesis will be utilized for some molecules to increase both the quantity and chemical diversity of potential leads. We will adhere to established guidlines such as the Lipinski "Rule of five" to increase our chances of obtaining drug like molecules. Analogs that show improved acivity will be subjected to ADME/PK studies in order to select for drug like leads. This process will be repeated until we achieve the profile of a CD described in Table 4. We would like to include yet another approach in our drug discovery of RNHI. We will exploit the generation of metabolites of some of our leads as a source of new chemotypes for identifyiing RNHI. We are very encouraged by the results that we obtained so far (Tablel). There is a strong correlation between the biochemical and cell-based values, some having an IC50<1uM with an excellent therapeutic Index >200. This represents a major step forward in identifying and developing RNHIs. It is a tribute to the plant cell culture technology that we developed so far. A highly diverse library that originated from more than 2200 plant species, representing 284 plant families, that is charecarized by a high reproducibility of secondary metabolite production. This project has enormous potential impact in delivering a new class of HIV drugs.