Pharmacy


Vial with DIGITALINE

Digitaline NATIVELLE, about 1911

 

 

"Nativelle prepared digitaline cristallisée, which at last was believed to be pure. Meanwhile a commercial distinction had been established between German digitalin (originating from Walz's preparation), an amorphous powder easily soluble in water and alcohol, less soluble in chloroform, and very little soluble in ether; and French crystalline digitalin (that of Homolle and Quevenne, and Nativelle), easily soluble in chloroform and alcohol, but hardly soluble in water and ether. In this connection it may be stated that the French Codex gives detailed directions for the preparation of both digitaline amorphe and digitaline cristallisée, the yield of the latter being 1 gram from each kilogram of leaves. To Schmiedeberg (1874) we are indebted for a critical study of the more important digitalins of commerce. He arrived at the conclusion that these preparations were composed mainly of the following principles: Digitonin, digitoxin, digitalin, and digitalein. The first is an inactive glucosid, while the three others have the property of acting upon the heart, digitoxin possessing this power in a most pronounced degree. The more recent researches of Kiliani have materially extended our knowledge of the chemical nature of these substances.

 


Digitoxin. This forms the main constituent of Nativelle's digitalin. It is insoluble in water, although the presence of other digitalis glucosids or extractive matters may render it more soluble. It dissolves freely in alcohol and chloroform, slightly in ether, but is insoluble in petroleum ether (Keller, 1897). It yields a precipitate with tannic acid, but not with basic acetate of lead. Schmiedeberg could not establish the presence of sugar as a constituent of  digitoxin, although he obtained toxiresin by the action of acids. Recently Kiliani succeeded in resolving digitoxin (C31H50O10), into digitoxigenin and a substance, digitoxose (C9H18O6), resembling sugar (Archiv. der Pharm., 1896, p. 481).