Inhibitor of FtsZ Polymerization in M. tuberculosis

描述（由申请方提供）：开发新的抗结核药物 代理商在全球范围内至关重要。我们的计划已经确定了一个新的 一类结核分枝杆菌（Mtb）抑制剂，可抑制一种新的 目前抗结核药物不靶向的蛋白质。的 2-烷氧基-羰基氨基-吡啶（2-ACP）有效地抑制结核分枝杆菌的生长 MIC 99（SRI-3072）低至0.15微克/ml（0.28微摩尔）。 此外，SRI-3072显示出杀菌活性，并且显示出显著的杀菌活性。 在鼠源性巨噬细胞模型中的活性，EC 90和EC 99为0.12， 1.42μ g/ml。这些类似物也显示出选择性活性 与哺乳动物细胞系相比。该计划成功地 确定了这些药物的靶点，即分枝杆菌微管蛋白同系物FtsZ。 目的蛋白已被大量克隆、表达和分离 足以开发体外聚合和GTP水解 测定。三种化合物，SRI-3072，SRI-76 14和秋水仙碱已被证明 以剂量依赖性方式抑制Mtb FtsZ聚合，IC 50为50 60 μ M和100 μ M。此外。我们已经证明SRI-7614 通过电子显微镜观察影响Mtb FtsZ聚合。SRI-7614也被 与一组单一耐药Mtb菌株相比显示出活性。我们 目前具有与柠檬酸盐、GTPgS和GDP结合的Mtb FtsZ的晶体结构。 迄今为止，已经在体外筛选了约200种抗Mtb H37 Rv的2-ACP类似物。 我们已经开发了一个SAR配置文件， 选择性和更有效的抗结核药物。在本申请中，我们 建议通过准备新的 更有效和选择性的亚类3-脱氮-蝶啶的类似物 （优先）和吡啶二氮卓类（备用）。我们将仔细评估这些 化合物在各种体外测定中的活性和选择性，包括 体外Mtb H37 Ra测定，体外Mtb FtsZ聚合和GTdR测定， 体外微管蛋白聚合测定和哺乳动物细胞毒性测定。 选定的活性剂将在体外巨噬细胞中进一步筛选 模型和Mtb小鼠模型。抑制剂对FtsZ聚合的影响 将使用电子显微镜进行分析。生物筛选数据 EM结构研究将反馈到化合物设计中， 交互式、迭代式药物设计周期，重点关注 抗菌效力和选择性。

DESCRIPTION (Provided by the applicant): Development of new antitubercular agents is of critical importance worldwide. Our program has identified a new class of inhibitor of Mycobacterium tuberculosis(Mtb) that inhibits a novel protein not presently targeted by current antitubercular agents. The 2-alkoxy-carbonylamino-pyridines (2-ACPs) potently inhibit the growth of Mtb with an MIC99 (SRI-3072) as low as 0.15 microgram/ml (0.28 micromolar). Furthermore, SRI-3072 shows bactericidal activity, and shows significant activity in a murine-derived macrophage model with an EC90 & EC99 of 0.12 and 1.42 microgram/ml respectively. These analogs also show selective activity against Mtb versus a mammalian cell line. This program has successfully identified the target of these agents, the mycobacterial tubulin homolog FtsZ. The target protein has been cloned, expressed and isolated in quantities sufficient for development of in vitro polymerization and GTP hydrolysis assays. Three compounds, SRI-3072, SRI-76 14, and colchicine have been shown to inhibit polymerization of Mtb FtsZ in a dose dependent manner with IC50S of 50 uM, 60 uM, and 100 uM respectively. Furthermore. we have shown that SRI-7614 affects Mtb FtsZ polymerization by electron microscopy. SRI-7614 has also been shown to be active vs. a panel of single drug-resistant Mtb strains. We currently have crystal structures of Mtb FtsZ bound to citrate, GTPgS, and GDP. To date, about 200 2-ACP analogs have been screened in vitro against Mtb H37Rv. We have developed a SAR profile that will allow the preparation of more selective and more potent antitubercular agents. In this application, we propose to continue development of the 2-ACP class through preparations of new analogs of the more potent and selective subclasses, the 3-deaza-pteridines (priority), and the pyridodiazepines (backup). We will carefully evaluate these compounds for activity and selectivity in various in vitro assays including an in vitro Mtb H37Ra assay, an in vitro Mtb FtsZ polymerization and GTPase assay, an in vitro tubulin polymerization assay and a mammalian cell toxicity assay. Selected active agents will be further screened in an h in vitro macrophage model and a Mtb mouse model. The effect of inhibitors on FtsZ polymerization will be analyzed using electron microscopy. Data from the biological screening and the EM structural studies will feed back into compound design in an interactive, iterative drug design cycle that critically focuses on antibacterial potency and selectivity.