Glycosides strophanthidin

All k-strophanthidin glycosides (T3-T7) fluoresce yellow-brown to white-green in UV. 

Fig. 8A Erysimi herba (1) and Cheiranthi herba (2) both show k-strophanthidin glycosides as major cardenolides, seen as violet-red zones (vis) in the Rf range 0.15-0.5.

Rothschild, M., H. Alborn, G. Stenhagen, and L. M. Schoon-hoven, a strophanthidin glycoside in Siberian wallflower A contact deterrent for the large white butterfly. Phytochemistry, 27, 101-108 (1988). 

Gibberellic acid and (2,4-dichlorophenoxy) acetic acid increased the glycoside content of Omithogalum umbellatum, as measured by a biological assay of extracts. The active principle, strophanthidin, is one of the cardiac glycosides. 7 There is little reference in the literature to this type of work, but the hydrolytic effects of gibberellic acid on starch may shift the equilibrium toward phenyl glycoside formation in some plant species. 

The dried roots and tops of lily of the valley, Convallaria majalis (Liliaceae/Convallariaceae), contain cardioactive glycosides (0.2-0.3%) and are used in some European countries rather than digitalis. The effects are similar, but the drug is less cumulative. This plant is widely cultivated as an ornamental, particularly for its intensely perfumed small white flowers, and must be considered potentially toxic. The major glycoside (40-50%) is convallatoxin (Figure 5.98), the rhamnoside of strophanthidin. 

For hydrolysis of the glycoside, 3 g. of cymarin is dissolved in 12 cc. of absolute alcohol. After addition of a mixture of 12 cc. of water and 6 cc. of concentrated hydrochloric acid (sp. gr. 1.19), the solution is allowed to stand for five to six hours in the cold. After the addition of 3 volumes of water, the alcohol is removed under reduced pressure, care being taken that the temperature does not rise above 30°. Crystallization of the strophanthidin begins shortly and is completed on standing overnight. The strophanthidin (2 g.) is collected and wa.shed with water. 

The aldehyde group of cardioactive glycosides and aglycones can also be selectively reduced. Hunger and Reichstein377 carried out such reactions with strophanthidin, convallatoxin, and similar compounds. 

Intramolecular Heck reaction. A significant application of this process is reported in the elaboration of the 5p-hydroxy-10p-hydroxymethyl structural motif" of the cardiac glycosides such as strophanthidin and ouabagenin. 

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