Chronic inflammation has been recognized as a significant leading cause of disability and mortality worldwide. More than 50% of deaths being attributed to inflammation-linked diseases such as stroke, cancers, kidney, and cardiovascular diseases. In searching for new potential anti-inflammatory agents, a novel piperine dimer and an amide series of piperine derivatives were designed, synthesized, and screened for their anti-inflammatory activity. Piperine was isolated from fruits of Piper longum L. and hydrolyzed under reflux conditions to obtain piperic acid as a starting material for the synthesis of the piperine derivatives. The conversion of piperic acid to an amide series was involving the N,N’-dicyclohexylcarbodiimide (DCC) coupling method in the presence of 4-dimethylamino pyridine (DMAP) as a catalyst. Meanwhile, the piperine dimer (7) was obtained by SiO₂-mediated Diels-Alder reaction of piperine. The isolated and synthesized compounds were elucidated using ¹H and ¹³C NMR spectroscopy. The anti-inflammatory activity of the compounds was determined by nitric oxide (NO) inhibition assay of LPS-activated macrophage J774.A1 cells and reported as IC₅₀ values. Among the compounds tested, compound 3 showed the most potent activity at an IC₅₀ value of 19.5 μM. Piperine (1) and its amide derivatives 4-6 showed moderate anti-inflammatory activity with IC₅₀ values in the range of 26.7-44.4 μM, whereas piperic acid (2) did not show any significant activity at 50 μM. These findings indicated that the amide moiety of the piperine derivatives might play an important role in their anti-inflammatory activity. Moreover, the cytotoxicity of all compounds against J774.A1 cells was evaluated using an MTT assay. None of the compounds showed cytotoxic to the cells, except compound 7 with the cell viability less than 80% at a dose of 50 μM.