Toxicity cardenolide

Cardiac glycosides are medicinally important steroids. Cardenolides are used in heart therapy, as emetics, diuretics, and purgatives. They affect the Na+/K+-ATPase and are very toxic at high doses. 

Glycoside diversification also has occurred in the coevolution of monarch butterflies and milkweeds (7). It may be desirable to relate the toxicity of cardenolides to the hydrolytic capabilities of susceptible and nonsusceptible insects. Cardenolides from Rsclepias species can be hydrolyzed by 3-glucosidases present in the plant (6), yet specialized Danans species are able to sequester these compounds, a process wh ich requires control of hydrolysis. 

Digitoxigenin glycoside) (cardenolide, cardiac glycoside) D. viridifbra (Scrophulariaceae) [leaf] toxic]... 

C. procera R.Br and toxicity F. Briischweiler et at., Helv. Chim. Acta 52, 2086 (1969). Revised structure eidem, ibid. 2276. Sequestration by larvae of Monarch butterfly Danaus plexippus L. 1. N. Sieber et al.. J. Chem. Ecol. 6, 321 (1980). Quantitative analysis of cardenolides in latex and leaves of C procera eidem. Phytochemistry 21, 2343 (1982). Biosynthesis of labelled compd M. S. Lee, J. N. Sieber, ibid. 22, 923 (1983). 

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