Norbergenin, the O-demethyl derivative of bergenin, shows moderate antioxidant activity (IC50 13 μM in DPPH radical scavenging; 32 μM in superoxide anion scavenging)[1].
References
[1] Takahashi H, et al. Synthesis and neuroprotective activity of bergenin derivatives with antioxidant activity. Bioorg Med Chem. 2003;11(8):1781-1788. DOI:10.1016/s0968-0896(02)00666-1
