n. [ Cf. F. digitaline. ] (a) (Medicine, Pharmacy) Any one of several extracts of foxglove (Digitalis), as the “French extract, ” the “German extract, ” etc., which differ among themselves in composition and properties. Both Digitalis lanata and Digitalis purpurea have been used to prepare such extracts. (b) (Chem.) the distinctive chemical substance, a steroid glycoside, which is the essential ingredient of the extracts of foxglove. It is a white, crystalline substance (C36H56O14), and is a 3-substituted diglucoside of a steroid. It is a powerful cardiac stimulant and is used as a cardiotonic for treatment of certain heart conditions, such as congestive heart failure. Chemically it is (3β, 5β, 16β)-3-[ 6-Deoxy-4-O-β-D-glucopyranosyl-3-O-methyl-β-D-galactopyranosyl)oxy ]-14, 16-dihyroxy-card-20(22)-enolide. The related compounds digitoxin and digoxin are also extracted from the foxglove. The class of steroid glycosides having cardiotonic properties are refered to as the cardiac glycosides. MI11 Syn. -- digitalinum verum, Diginorgin, Schmiedeberg's digitalin, digitalis, digitalis glycoside. [ 1913 Webster +PJC ]
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