Dalea emoryi revisited: Anthelmintic and new components of a previously-studied plant

Detailed chemical studies of Dalea emoryi A. Gray (syn: Psorothamnus emoryi (A. Gray) Rydb. (Fabaceae) were undertaken using taxonomic rationale. Other Dalea spp. have yielded anthelmintic components in our biological testing. D. emoryi was the subject of prior studies, and, interestingly, the crude extract was inactive in our bioassay. Nevertheless, new and active compounds 1 and 2, for example, were revealed upon further purification of the crude D. emoryi materials. These findings agree with prior observations regarding the importance of screening partially purified materials in addition to crude extracts. Anthelmintic activities were determined in an ex vivo assay with the hookworm Ancylostoma ceylanicum. Isolation of compounds was by classical open-column chromatographic methods, with characterization using extensive 1D and 2D NMR spectroscopic methods and by HRESIMS. Details of the bioassay methods, results, and the isolation and characterization of D. emoryi compounds will be presented.