New caffeoyl derivatives from Elephantopus scaber

Three new caffeoyl derivatives (1–3), together with two known ones (4–5), were isolated from the whole plant of Elephantopus scaber Linn. The structures of the new compounds were elucidated using detailed spectroscopic analysis. Compound 4 was obtained and its NMR data were given for the first time. All isolates were evaluated for their anti-inflammatory activity against lipopolysaccharide (LPS)-stimulated nitric oxide (NO) production and pro-inflammatory cytokines release in RAW 264.7 cells. Compounds 2–5 showed mild inhibitory activities with IC50 values ranging from 64.78 to 87.21 μM, and 3–4 could inhibit LPS-induced tumor necrosis factor-α (TNF-α) production.