Two spasmolytic diterpene acids, ent-beyer-15-en-19-oic acid and ent-kaur-16-en-19-oic acid, have been isolated from the roots of Viguiera hypargyrea by bioassay-guided fractionation. Beyerenoic acid was also active against Staphylococcus aureus, Enterococcus feacalis and Candida albicans.
The research, development and use of natural products as therapeutic agents, especially those derived from plants, have been increasing in recent years. Despite the fact that plants provide a rich source of novel biologically active compounds, only a small percentage have been phytochemically