Two New Isoflavones from Phlomis betonicoides and Their Antioxidant Activity

摘要

Two new isoflavones derivatives, 8,4 ' -dimethoxy-7-(3-hydroxypropyl)-isoflavone (1) and 8,4 ' -dimethoxy-7-(3-hydroxypropanoyl)-isoflavone (2), were isolated from the roots of Phlomis betonicoides. Their structures were elucidated by spectroscopic methods, including extensive 1D and 2D NMR techniques. Compounds 1 and 2 were also tested for the antioxidant activity, and they show good antioxidant activity with an IC50 value of 3.8 and 3.6 mu g/mL, respectively.