by semisynthesis of a major component 1-O-acetylbritannilactone (ABL) from the traditional Chinese medicinal herb Inula Britannica L. Compound 15 was identified as a promising anti-neuroinflammatory agent by nitrite oxide (NO) production screening. 15 could attenuate tumor necrosis factor-α (TNF-α) and prostaglandin E2 (PGE2) productions, and inhibit the expression of inducible nitric oxide synthase