Subalpinoside (S1), an Unknown Oleandrigenin Glycoside and Other Cardenol from Digitalis subalpina var. subalpina.

From the leaves of DIGITALIS SUBALPINA Br.-Bl. var. SUBALPINA an oleandrigenin glycoside was isolated as the main cardiotonic compound besides some known glycosides such as evatromonoside, lanatoside A and B, gitoroside, and others. The structure of this compound was elucidated by spectroscopic methods ( (1)H-, (13)C-, 2D-NMR spectroscopy) as gluco-oleandrigenin digitoxoside. This is the first report of the occurrence of oleandrigenin derivatives in a DIGITALIS species.