The non-canonical IκB kinases TANK-binding kinase 1 (TBK1) and inhibitor of nuclear factor kappa-B kinase ε (IKKε) play a key role in insulin-independent pathways that promote energy storage and block adaptive energy expenditure during obesity. Utilizing docking calculations and the x-ray structure of TBK1 bound to amlexanox, an inhibitor of these kinases with modest potency, a series of analogues was synthesized to develop a structure activity relationship (SAR) around the A- and C-rings of the core scaffold. A strategy was developed wherein R₇ and R₈ A-ring substituents were incorporated late in the synthetic sequence by utilizing palladium-catalyzed cross-coupling reactions on appropriate bromo precursors. Analogues display IC₅₀ values as low as 210 nM and reveal A-ring substituents that enhance selectivity toward either kinase. In cell assays, selected analogues display enhanced phosphorylation of p38 or TBK1 and elicited IL-6 secretion in 3T3-L1 adipocytes better than amlexanox. An analogue bearing a R₇ cyclohexyl modification demonstrated robust IL-6 production in 3T3-L1 cells as well as a phosphorylation marker of efficacy and was tested in obese mice where it promoted serum IL-6 response, weight loss, and insulin sensitizing effects comparable to amlexanox. These studies provide impetus to expand the SAR around the amlexanox core toward uncovering analogues with development potential.

非经典 IκB 激酶 TANK 结合激酶 1 (TBK1) 和核因子 kappa-B 激酶 ε 抑制剂 (IKKε) 在胰岛素依赖性途径中发挥着关键作用，可促进能量储存并阻止肥胖期间的适应性能量消耗。利用对接计算和 TBK1 与 amlexanox（这些激酶的抑制剂，具有中等效力）结合的 X 射线结构，合成了一系列类似物，以开发核心 A 环和 C 环周围的结构活性关系 (SAR)脚手架。开发了一种策略，其中通过在适当的溴前体上利用钯催化的交叉偶联反应，将R ₇和R ₈ A环取代基并入合成顺序的后期。类似物的 IC ₅₀值低至 210 nM，并揭示了 A 环取代基，可增强对任一激酶的选择性。在细胞测定中，选定的类似物显示出增强的 p38 或 TBK1 磷酸化，并比 amlexanox 更好地引发 3T3-L1 脂肪细胞中的 IL-6 分泌。带有 R ₇环己基修饰的类似物在 3T3-L1 细胞中表现出强大的 IL-6 产生以及磷酸化功效标记物，并在肥胖小鼠中进行了测试，其促进血清 IL-6 反应、体重减轻和胰岛素增敏效果相当氨来呫诺。这些研究为扩大氨来呫诺核心的 SAR 提供动力，以发现具有开发潜力的类似物。