A new flavonoid isolated from Brandisia hancei Hook. f. and anti-inflammatory activity

A new flavonoid derivative, (2 R, 3 R)-5,7,3',4',5'-pentamethoxyflavan-3-O-β-D-glucopyranose (1), along with ten known flavonoids, was obtained from Brandisia hancei Hook. f. via ethanol extraction and chromatographic separation. The chemical structure of compound 1, including its absolute configuration, was determined using a combination of UV, IR, HR-ESI-MS, and various NMR techniques. To assess anti-inflammatory properties, compounds 1-9 were tested for their ability to suppress nitric oxide (NO) generation in LPS-activated RAW264.7 macrophages. Screening data indicated that compounds 1 (IC₅₀ = 112.8 μg/mL), 4 (IC₅₀ = 16.81 μg/mL), and 8 (IC₅₀ = 0.68 μg/mL) displayed considerable NO-inhibitory activity. Further mechanistic studies on these three isolates revealed that compound 4 markedly reduced the secretion of TNF-α and IL-6, with corresponding IC₅₀ values of 31.08 μg/mL and 22.99 μg/mL, respectively.