Three new xanthones and other anti-inflammatory components from the aerial parts of Hypericum beanii.

Abstract

Hypericum beanii, a traditional folk medicine plant, has been employed in treating various inflammation-related diseases. In this study, three new prenylated xanthones, named beanigenin A (1), beanigenin B (2), and beanigenin C (3), along with twenty-five known compounds (4-28), were isolated from the aerial parts of H. beanii. The new xanthones were elucidated based on modern spectroscopic experiments, including nuclear magnetic resonance spectroscopy (NMR) techniques, high-resolution electrospray ionization mass spectroscopy (HR-ESI-MS), and electronic circular dichroism (ECD). All the compounds were evaluated for their anti-inflammatory effects by measuring their inhibitory effect on nitric oxide (NO) production in LPS-stimulated RAW 264.7 macrophages. Our findings showed that compounds 1-10, 12, 14, 21-23, 26, and 28 displayed significant anti-inflammatory effects, with IC₅₀ values ranging from 0.82 to 9.71 μM. The MOE software was utilized to conduct an in silico evaluation of the potential inhibitory activity of the three new xanthones against inducible NO synthase (iNOS) and cyclooxygenase 2 (COX-2) proteins. The results indicated that the three new xanthones demonstrated a high binding affinity with both iNOS and COX-2 proteins.