Mollugin Derivatives as Anti-Inflammatory Agents: Design, Synthesis, and NF-κB Inhibition.

Nuclear factor κB (NF-κB) is a key inducible transcription factor that controls a large number of genes involved in inflammatory and immune processes. The entire inflammation-mediated process uses NF-κB as a hub, and inflammatory gene transcription and expression can be decreased by blocking the NF-κB signaling pathway, thereby reducing inflammatory damage. Therefore, the inhibition of this pathway is an important therapeutic target for the treatment of various types of inflammation. Here, we designed and synthesized 27 mollugin derivatives and evaluated the anti-inflammatory activity against NF-κB transcription. Most of the compounds exhibited potent anti-inflammatory activity, and compound 5k was the most potent with 81.77% inhibition after intraperitoneal administration, which was significantly more potent than mollugin (49.72%), ibuprofen (47.51%), and mesalazine (47.24%). Investigation of the mechanism of action indicated that 5k down-regulated NF-κB expression, possibly by suppressing LPS-induced expression of the p65 protein. ADMET prediction analysis indicated that compounds 5h and 5k showed good pharmacokinetic properties. The relationship between the structures of the synthesized compounds and the NF-κB inhibitory activity was rationalized using molecular docking simulation experiments. Overall, these results provide an initial basis for the development of 5h and 5k as potential anti-inflammatory agents.