Helleborus Bufadienolides

The bufadienolides occur in plants as well as animals, but only in plants are they in the form of glycosides. Their 3-hydroxyl group is attached lo glucose, rhamnose, or thevetosc. Hellebrigenin (Fig. 2). which is also known as bufotalidin. occurs in the rhizomes of the Christmas rose and other Helleborus species in the form of a rhamnoside. Bufadienolides have so far been found in plants in only two families, the buttercup and the lily family. 

Watanabe K, Mimaki Y, Sakagami H, Sashida Y (2003) Bufadienolide and Spirostanol Glycosides from the Rhizomes of Helleborus orientalis. J Nat Prod 66 236... 

Cardiac glycosides occur in several famihes of higher plants, e.g., Liliaceae, Ranunculaceae, Asclepiadaceae, Apocynaceae, and Scrophulariaceae. Cardeno-lides are the most widespread derivatives. Bufadienolides have been isolated from only a few genera, e.g., Scilla (Liliaceae) and Helleborus (Ranunculaceae). In addition cardenolides are synthesized in certain beetles and bufadienolides in toads Bufo sp.). The cardenolides found in the locust Poekilocerus bufonius the butterfly Danaus plexippus and several other animals are derived from cardiac glycosides taken up with the diet (E 5.1). 

As the name implies, bufadienolides are found in the secretions of toads (Bufo). They are also present in plants. One such is hellebrigenin from the rhizomes of the black hellebore (Helleborus niger). The bio-... 

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