The ability of G protein-coupled receptor (GPCR) kinases (GRKs) to regulate the desensitization of GPCRs has made GRK2 and GRK5 attractive targets for treating diseases such as heart failure and cancer. Previously, our work showed that Cys474, a GRK5 subfamily-specific residue located on a flexible loop adjacent to the active site, can be used as a covalent handle to achieve selective inhibition of GRK5 over GRK2 subfamily members. However, the potency of the most selective inhibitors remained modest. Herein, we describe a successful campaign to adapt an indolinone scaffold with covalent warheads, resulting in a series of 2-haloacetyl-containing compounds that react quickly and exhibit three orders of magnitude selectivity for GRK5 over GRK2 and low nanomolar potency. They however retain a similar selectivity profile across the kinome as the core scaffold, which was based on Sunitinib.

中文翻译：

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产生高选择性、强效和共价 G 蛋白偶联受体激酶 5 抑制剂

G 蛋白偶联受体 (GPCR) 激酶 (GRK) 调节 GPCR 脱敏的能力使 GRK2 和 GRK5 成为治疗心力衰竭和癌症等疾病的有吸引力的靶标。以前，我们的工作表明 Cys474 是一种 GRK5 亚家族特异性残基，位于与活性位点相邻的柔性环上，可用作共价手柄以实现对 GRK2 亚家族成员的 GRK5 选择性抑制。然而，最具选择性的抑制剂的效力仍然不大。在这里，我们描述了一项成功的活动，以使吲哚酮支架与共价弹头相适应，从而产生一系列含有 2-卤代乙酰基的化合物，这些化合物反应迅速，对 GRK5 的选择性比 GRK2 高三个数量级，并且具有低纳摩尔效力。