Isoflavones and lignans with anti-inflammatory activity from Thalictrum baicalense Turcz

Phytochemical investigation of Thalictrum baicalense Turcz. roots, traditionally used for inflammatory conditions, led to the isolation of three novel isoflavones, thalibaicalins A-C (1-3), and a new lignan, (7R, 8S, 7'R, 8'S)-9E-feruloylneoolivill (6), alongside six known compounds (4-5, 7-10). Structural characterization was accomplished by HRESIMS, comprehensive NMR analysis, and quantum chemical calculations. Anti-inflammatory evaluation in lipopolysaccharide-stimulated RAW 264.7 macrophages identified potent NO inhibitors, with lignan 6 exhibiting the highest activity (IC₅₀ = 9.56 ± 2.03 μM). This study expands the phytochemical diversity of T. baicalense Turcz. and highlights its potential as a source of anti-inflammatory lead compounds, particularly the highly active lignan derivative.