SMU-14a is a TLR3 inhibitor with an IC50 of 0.18 µM. It suppresses IL-6 secretion in mouse peritoneal macrophages and downregulates TNF-α in human peripheral blood mononuclear cells. The compound exerts anti-inflammatory effects by reducing the phosphorylation of p65, ERK, and TBK1 via the NF-κB, MAPK, and IRF3 signaling pathways, and by lowering serum levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST). SMU-14a is applicable in acute hepatitis research.