The UDP-2,3-diacylglucosamine pyrophosphate hydrolase LpxH is essential in lipid A biosynthesis and has emerged as a promising target for the development of novel antibiotics against multidrug-resistant Gram-negative pathogens. Recently, we reported the crystal structure of Klebsiella pneumoniae LpxH in complex with 1 (AZ1), a sulfonyl piperazine LpxH inhibitor. The analysis of the LpxH-AZ1 co-crystal structure and ligand dynamics led to the design of 2 (JH-LPH-28) and 3 (JH-LPH-33) with enhanced LpxH inhibition. In order to harness our recent findings, we prepared and evaluated a series of sulfonyl piperazine analogs with modifications in the phenyl and N-acetyl groups of 3. Herein, we describe the synthesis and structure–activity relationship of sulfonyl piperazine LpxH inhibitors. We also report the structural analysis of an extended N-acyl chain analog 27b (JH-LPH-41) in complex with K. pneumoniae LpxH, revealing that 27b reaches an untapped polar pocket near the di-manganese cluster in the active site of K. pneumoniae LpxH. We expect that our findings will provide designing principles for new LpxH inhibitors and establish important frameworks for the future development of antibiotics against multidrug-resistant Gram-negative pathogens.

UDP-2,3-二酰基葡萄糖胺焦磷酸水解酶 LpxH 在脂质 A 生物合成中必不可少，并且已成为开发针对多重耐药革兰氏阴性病原体的新型抗生素的有希望的目标。最近，我们报道了与磺酰哌嗪 LpxH 抑制剂1 ( AZ1) 复合的肺炎克雷伯菌LpxH的晶体结构。LpxH-AZ1 共晶结构和配体动力学的分析导致设计了具有增强的 LpxH 抑制的2 (JH-LPH-28) 和3 (JH-LPH-33)。为了利用我们最近的发现，我们制备并评估了一系列磺酰基哌嗪类似物，它们的苯基和N-乙酰基修饰了3. 在此，我们描述了磺酰哌嗪 LpxH 抑制剂的合成和构效关系。我们还报告了与肺炎克雷伯菌LpxH复合的扩展N-酰基链类似物27b (JH-LPH-41)的结构分析，揭示了27b到达了K的活性位点中二锰簇附近未开发的极袋. 肺炎LpxH。我们希望我们的发现将为新的 LpxH 抑制剂提供设计原则，并为未来针对多重耐药革兰氏阴性病原体的抗生素开发建立重要框架。