Suaeglaucin B, an Isoflavone from Suaeda glauca, and its Antioxidant Activity

Suaeglaucin B (7-hydroxy-3-(2-hydroxyphenyl)-5,6-dimethoxy-4H-chromen-4-one, 1), an isoflavone, including seven other known compounds (2–8), was isolated for the first time from the herbs of Suaeda glauca (Bunge) Bunge. In this article, the extraction and isolation of these compounds is carried out, and the structures of eight compounds (1–8) were established using chemical methods including HR-ESI-MS and 1D, 2D NMR spectroscopy. In addition, the antioxidant activity of compound 1, with IC50 value of 1.63 mM, was evaluated by the 1,1-diphenyl-2-picrylhydrazyl free radical (DPPH) assay.