digitoxin

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun A highly active glycoside, C₄₁H₆₄O₁₃, derived from digitalis and prescribed in the treatment of certain cardiac conditions.

from The Century Dictionary.

• noun A poisonous principle obtained from Digitalis in the form of yellowish crystals soluble in alcohol.

from the GNU version of the Collaborative International Dictionary of English.

• noun (Chem.) A steroid glycoside, one of the cardiotonic chemical substances which is extracted from the foxglove. It is a white, crystalline substance (C41H64O13), and is a 3-substituted triglucoside of a steroid, related structurally to digitalin and digoxin. It is used as a cardiotonic for treatment of certain heart conditions, such as congestive heart failure. Chemically it is (3β,5β)-3-[(O-2,6-Dideoxy-β-D-ribo-hexopyranosyl-(1→4)-O-2,6-dideoxy-β-D-ribo-hexopyranosyl-(1→4)-2,6-dideoxy-β-D-ribo-hexopyranosyl)oxy]-14-hydroxy-card-20(22)-enolide. The related compounds digitalin and digoxin are also extracted from the foxglove (Digitalis lanata and Digitalis purpurea). The class of steroid glycosides having cardiotonic properties are refered to as the cardiac glycoside group.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun organic chemistry A toxic cardiac glycoside, obtained from digitalis, related to cardenolide

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun digitalis preparation used to treat congestive heart failure or cardiac arrhythmia