Phenolic compounds from the Mongolian medicinal plant Scorzonera radiata.

Chromatographic separation of a crude extract obtained from aerial parts of the Mongolian medicinal plant Scorzonera radiata yielded fifteen natural compounds, including two new flavonoids and one new quinic acid congener, as well as four flavones and eight quinic acid derivatives, all of which are known natural compounds. The structures of the isolated compounds were elucidated on the basis of NMR (1H, 13C, COSY, HMBC, ROESY, and TOCSY) and mass spectrometric data. The antioxidant activities of the quinic acid derivatives were evaluated by the DPPH assay.