Dynamic combinatorial chemistry (DCC) leverages a reversible reaction to generate compound libraries from constituting building blocks under thermodynamic control. The position of this equilibrium can be biased by addition of a target macromolecule towards enrichment of bound ligands. While DCC has been applied to select ligands for a single target protein, its application to identifying chimeric molecules inducing proximity between two proteins is unprecedented. In this proof‐of‐concept study, we develop a DCC approach to select bifunctional proteolysis targeting chimeras (PROTACs) based on their ability to stabilize the ternary complex. We focus on VHL‐targeting Homo‐PROTACs as model system, and show that the formation of a VHL2:Homo‐PROTAC ternary complex reversibly assembled using thiol‐disulfide exchange chemistry leads to amplification of potent VHL Homo‐PROTACs with degradation activities which correlated well with their biophysical ability to dimerize VHL. Ternary complex templated dynamic combinatorial libraries allowed identification of novel Homo‐PROTAC degraders. We anticipate future applications of ternary‐complex directed DCC to early PROTAC screenings and expansion to other proximity‐inducing modalities beyond PROTACs.

中文翻译：

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用于选择和鉴定均质 PROTAC 的三元络合物模板动态组合化学

动态组合化学 (DCC) 利用可逆反应在热力学控制下通过构建模块生成化合物库。通过添加目标大分子可以使该平衡的位置偏向于结合配体的富集。虽然 DCC 已应用于选择单个靶蛋白的配体，但其在识别诱导两种蛋白之间接近的嵌合分子方面的应用是前所未有的。在这项概念验证研究中，我们开发了一种 DCC 方法，根据双功能蛋白水解靶向嵌合体 (PROTAC) 稳定三元复合物的能力来选择它们。我们重点关注 VHL 靶向 Homo-PROTAC 作为模型系统，并表明使用硫醇-二硫化物交换化学可逆组装的 VHL2:Homo-PROTAC 三元复合物的形成导致有效的 VHL Homo-PROTAC 的扩增，其降解活性与相关性良好具有使 VHL 二聚化的生物物理能力。三元复合物模板化动态组合库允许鉴定新型 Homo-PROTAC 降解剂。我们预计三元复合物定向 DCC 未来将应用于早期 PROTAC 筛选，并扩展到 PROTAC 之外的其他接近诱导模式。