Vitamin B17
Vitamin B17 or Amygdalin is extracted from almond or apricot kernel cake by boiling ethanol. Vitamin B17 or Amygdalin is precipitated as white minute crystals on evaporation of the solution and the addition of diethyl ether. Liebig and Wöhler were already able to find three decomposition products of the newly discovered amygdalin: sugar, benzaldehyde, and prussic acid. Later research showed that sulfuric acid decomposes it into d-glucose, benzaldehyde, and prussic acid (hydrogen cyanide); while hydrochloric acid gives mandelic acid, d-glucose, and ammonia.
The decomposition induced by enzymes may occur in two ways. Maltase partially decomposes it, giving d-glucose and mandelic nitrile glucoside, C6H5CH(CN)O•C6H11O5; this compound is isomeric with sambunigrin, a glucoside found by E.E. Bourquelot and Danjou in the berries of the Common Elder, Sambucus nigra. Emulsin, on the other hand, decomposes it into benzaldehyde, cyanide, and two molecules of glucose; this enzyme occurs in the bitter almond, and consequently the seeds invariably contain free cyanide and benzaldehyde. An "amorphous amygdalin" is said to occur in the cherry-laurel. Closely related to these glucosides is dhurrin, C14H17O7N, isolated by W. Dunstan and T. A. Henry from the common sorghum or "great millet," Sorghum vulgare; this substance is decomposed by emulsin or hydrochloric acid into d-glucose, cyanide, and 4-hydroxybenzaldehyde.
Natural Vitamin B17 or Amygdalin has the R configuration at the chiral benzyl center. Under mild basic conditions, this stereogenic center epimerizes; the S epimer is called neoamygdalin.
Vitamin B17
OTHER RELATED INFORMATION
Vitamin B17 or Amygdalin is extracted from almond or apricot kernel cake by boiling ethanol. Vitamin B17 or Amygdalin is precipitated as white minute crystals on evaporation of the solution and the addition of diethyl ether. Liebig and Wöhler were already able to find three decomposition products of the newly discovered amygdalin: sugar, benzaldehyde, and prussic acid. Later research showed that sulfuric acid decomposes it into d-glucose, benzaldehyde, and prussic acid (hydrogen cyanide); while hydrochloric acid gives mandelic acid, d-glucose, and ammonia.
The decomposition induced by enzymes may occur in two ways. Maltase partially decomposes it, giving d-glucose and mandelic nitrile glucoside, C6H5CH(CN)O•C6H11O5; this compound is isomeric with sambunigrin, a glucoside found by E.E. Bourquelot and Danjou in the berries of the Common Elder, Sambucus nigra. Emulsin, on the other hand, decomposes it into benzaldehyde, cyanide, and two molecules of glucose; this enzyme occurs in the bitter almond, and consequently the seeds invariably contain free cyanide and benzaldehyde. An "amorphous amygdalin" is said to occur in the cherry-laurel. Closely related to these glucosides is dhurrin, C14H17O7N, isolated by W. Dunstan and T. A. Henry from the common sorghum or "great millet," Sorghum vulgare; this substance is decomposed by emulsin or hydrochloric acid into d-glucose, cyanide, and 4-hydroxybenzaldehyde.
Natural Vitamin B17 or Amygdalin has the R configuration at the chiral benzyl center. Under mild basic conditions, this stereogenic center epimerizes; the S epimer is called neoamygdalin.
Vitamin B17
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