Linus Pauling Institute

A new isoflavonoid, xanthocerin J, along with previously described xanthocerin A, were isolated from a methanol extract of aerial parts of a traditional American Indian herb, Pursh (Asteraceae). The structures of these compounds were characterized using mass spectrometry and NMR based on an isolation protocol using magnetic microbead affinity selection screening (MagMASS) for ligands to the estrogen receptor alpha (ERα). These compounds bound to ERα from an active fraction that exhibited dose-dependent antiestrogenic activity in the Ishikawa assay. However, these compounds did not exhibit antiestrogenic activity in the cell-based Ishikawa assay. Xanthocerin A and J may exhibit synergistic or additive activity with other compounds found in which needs further exploration. This work highlights the potential of as a prospect for the future discovery of compounds for women's health related to estrogen pathways.