Phytochemical Constituents of the Aerial Parts of Artemisia iwayomogi Kitamura and Their Anti-inflammatory Activities

Artemisia iwayomogi Kitamura is a well-known medicinal plant widely utilized in traditional medicine for its various pharmacological properties. In this study, phytochemical investigation of the aerial parts of A. iwayomogi led to the isolation and characterization of 13 secondary metabolites, including one new (1) and 12 known compounds (2–13). The structural elucidation of the new compound was achieved through comprehensive spectroscopic analysis, including NMR and HRMS data, and a modified Mosher’s method. This study represents the first report of compounds 2, 3, 5, and 13 from this plant species. Compound 1 was evaluated for its inhibitory activity against NO production in LPS-stimulated macrophages. However, it was found to be inactive against NO production (IC50 > 100 µM). In silico target prediction using SwissTargetPrediction identified catechol O-methyltransferase (COMT) as the highest-probability predicted target of compound 1, providing a hypothesis-generating basis for future biological investigation.