Anti-inflammatory activity of phenolics from Hypericum japonicum

Two new phenolics, one xanthonoid (1) and one phloroglucinol derivative (2), together with eighteen known phenolics (3–20), were isolated from the aerial parts of Hypericum japonicum. Their structures were established by extensive spectral analysis, and the absolute configuration of compound 1 was determined by comparison of the calculated and experimental circular dichroism spectra. An anti-inflammatory activity assay revealed that compound 1 exhibited effective inhibitory effects on NO generation in LPS-stimulated RAW 264.7 macrophages, with an IC50 value of 6.34 μg/mL.