Phenolic compounds from Coreopsis tinctoria Nutt. and their anti-inflammatory activity

Coreopsis tinctoria Nutt., a traditional edible and medicinal plant, is recognized for its bioactive compounds with potential health benefits. In this study, eight previously unreported compounds including a biflavone (1), an acylated flavonol glycoside (2), an acylated aurone glycoside (3), five phenolic bisabolane-type sesquiterpenoids (4-8), along with nine known compounds, were isolated and structurally elucidated using NMR, HRESIMS, ECD, and quantum chemical calculations. Compounds 7 and 9 showed moderate inhibition of nitric oxide production in LPS-induced RAW 264.7 cells, with IC₅₀ values of 24.56 ± 0.62 μM and 17.72 ± 0.53 μM, respectively. In the ELISA assays, compound 9 reduced the production of pro-inflammatory cytokines, including TNF-α and IL-6. Network pharmacology and molecular docking analyses revealed that compound 9 exerted anti-inflammatory effects via multiple pathways, and exhibited high binding affinity for potential key targets associated with anti-inflammatory activity. Furthermore, molecular dynamics simulations confirmed the stability of those complexes. These findings provide preliminary evidence for the potential of bisabolane-type sesquiterpenoids as lead compounds for developing anti-inflammatory ingredients.