A β-glycoside consisting of one mole strophanthidin and one mole d-digitoxose. Isoln from Erysimum helveticum (Jacq.) DC. and Erysimum crepidifolium Reichenb., Cruciferae, and structure: Nagata et al., Helv. Chim. Acta 40, 41 (1957); eidem, Festschr. Arthur Stoll 1957, 715; Gmelin, DE 1221764 (1966). From Erysimum spp.: Kowalewski, Helv. Chim. Acta 43, 1314 (1960). Toxicity study: Graebner, Giesel, Arzneim.-Forsch. 22, 1854 (1972).