Design, optimization and mechanism of action of novel HIV-1 entry inhibitors

 描述（由申请人提供）：随着耐药菌株的出现和与当前治疗相关的累积毒性，仍然需要新的HIV-1复制抑制剂。抑制HIV-1进入是一种有吸引力的治疗方法，对HIV/AIDS治疗方案具有广泛意义。结合计算机辅助药物设计技术，基于化合物的新型力场表示，与药物化学，我们设计并合成了新型HIV-1进入抑制剂，其代表了HIV-1进入抑制剂类的5种新的不同核心化学型。这些化合物具有低毒性，纳摩尔效力（0.6-100 nM），并且对HIV-1具有特异性。此外，我们已经确定了一种化合物，其代谢稳定性优于目前开发中的同类最佳进入抑制剂。在这项研究中，我们建议进一步开发这些新的进入抑制剂化合物的临床相关的效力，并改善其ADME/PK特征，同时也使用它们作为分子工具来剖析HIV-1进入宿主细胞的生物学。拟议研究的目标将通过三个独立但高度综合的具体目标来实现。在目标1中，将通过计算机模拟方法优化先导化合物，包括生物电子等排置换和药物样质量预测，以及药物化学。在目标2中，将评估类似物的抗病毒效力、广度和特异性。将平行进行其毒性评价。将通过体外和体内方法评估ADME和PK，并在HIV-1感染的人源化骨-肝-胸腺（BLT）小鼠模型中确定疗效。在目标3中，我们将进行详细的作用机制研究，产生抗性突变体，并使用互补结构技术（包括X射线晶体学，cryo-EM和负染色单粒子电子显微镜）研究化合物的结合位点。这些研究的数据将用于未来开发具有高遗传屏障和独特作用模式的下一代Env靶向抑制剂。这些化合物还将作为HIV-1 Env功能的分子探针，除了阐明难以捉摸的脆弱位点的细节之外，还为Env分子机器进行的复杂的一系列结构转变提供了新的见解。

 DESCRIPTION (provided by applicant): With the emergence of drug-resistant strains and the cumulative toxicities associated with current therapies, demand remains for new inhibitors of HIV-1 replication. The inhibition of HIV-1 entry is an attractive therapeutic approach with broad implications for HIV/AIDS treatment regimens. Combining computer-aided drug design techniques, based upon novel force field representations of compounds, with medicinal chemistry, we have designed and synthesized novel inhibitors of HIV-1 entry, which represent 5 new distinct core chemotypes for the HIV-1 entry inhibitor class. These compounds have low toxicity, nanomolar potency (0.6-100 nM), and are specific to HIV-1. Moreover, we have identified a compound with improved metabolic stability over the current best-in- class entry inhibitor in development. In this study, we propose to further develop these novel entry inhibitor compounds to potencies that are clinically relevant and improve their ADME/PK profiles, whilst also using them as molecular tools to dissect the biology of HIV-1 entry into host cells. The goals of the proposed studies will be accomplished by three discrete but highly integrated specific aims. In Aim 1, the leads will be optimized through in silico approaches, including bioisosteric replacement and prediction of drug-like qualities, coupled to medicinal chemistry. In Aim 2, the antiviral potency, breadth, and specificity of the analogues will be assessed. Evaluation of their toxicity will be performed in parallel. ADME and PK will be assessed via in vitro and in vivo methodologies, and the efficacy will be determined in the humanized bone-liver-thymus (BLT) mouse model of HIV-1 infection. In Aim 3, we will perform detailed mechanism-of-action studies, generate resistance mutants, and investigate the binding site of the compounds using complementary structural techniques including X-ray crystallography, cryo-EM, and negative-stain single-particle electron microscopy. The data from these studies will be used in the future development of next-generation Env-targeted inhibitors with high genetic barriers and unique modes of action. Such compounds will also serve as molecular probes for HIV-1 Env functions, providing novel insight into the complex series of structural transitions through which the Env molecular machine proceeds, in addition to illuminating the details of an elusive site of vulnerability.