Three new prenylated C6-C3 compounds (1-3), together with two known prenylated C6-C3 compounds (4-5) and one known C6-C3 derivative (6), were isolated from the roots of Illicium brevistylum A. C. Smith. The structures of 1-3 were elucidated by spectroscopic methods including 1D and 2D NMR, HRESIMS, CD experiments and ECD calculations. The structure of illibrefunone A (1) was confirmed by single-crystal X-ray diffraction analysis. All compounds were evaluated in terms of their anti-inflammatory potential on nitric oxide (NO) generation in lipopolysaccharide-stimulated murine RAW264.7 macrophages and murine BV2 microglial cells, antiviral activity against Coxsackievirus B3 (CVB3) and influenza virus A/Hanfang/359/95 (H3N2). Compounds 3 and 4 exhibited potent inhibitory effects on the production of NO in RAW 264.7 cells with IC50 values of 20.57 and 12.87 μM respectively, which were greater than those of dexamethasone (positive control). Compounds 1 and 4-6 exhibited weak activity against Coxsackievirus B3, with IC50 values ranging from 25.87 to 33.33 μM.
Keywords: Illicium brevistylum; anti-Coxsackievirus B3; anti-inflammatory activity; anti-influenza virus A; prenylated C6–C3 derivatives; roots.