447. ASPIDOSPERMA.—QUEBRACHO. (U.S.P. IX.) The bark of Aspidosper'ma quebra'cho blancho Schlechtendal. Thick, flat pieces (from 2/5 to 1 in. in thickness), with a very thick, yellowish-gray cork, which constitutes more than one-half of its entire substance, and is separated from the lower layer by a more or less sharply defined outline, deeply fissured, and traversed by parallel yellowish lines; between these lines are whitish dots visible in a cross-section scattered through both the outer and inner layers. Internally reddish-brown to yellow; odor slight; taste aromatic and bitter. Constituents: Aspidosperma is very rich in alkaloids, six having been discovered thus far; the most important are aspidospermine, C22H30N2O2, and quebrachine, C21H26N2O2. A peculiar sugar, quebrachite, is also present, and tannin, 3 to 4 per cent. Cardiac tonic. Its special action, however, is upon the respiration, lessening the rate and increasing the amplitude of the respiratory movements; it is chiefly used in asthmatic dyspnoea. Dose: 5 to 30 gr. (0.3 to 2 Gm.).
Powder.—Microscopical elements of: See Part iv, Chap. I, B.
Preparation of Aspidospermine.—Treat alcoholic extract with alkaline chloroform; dissolve chloroformic extract in acidulated (H2SO4) water and precipitate with NaOH; dissolve precipitate (mixed alkaloids) in boiling alcohol and cool, when alkaloids will crystallize.
To separate aspidospermine, crystallize from dilute HCl, when this alkaloid will remain in the mother liquor, from which it may be removed by neutralization and recrystallization. As found in commerce, this alkaloid is a mixture of this and the other associated principles, among which quebrachine is the most important. Crude aspidospermine sulphate is a commercial article, is deliquescent and unstable; it is much more soluble in water than the alkaloid.
Fluidextractum Aspidospermatis Dose: 5 to 30 drops (0.3 to 2 Mils).