SOLANIN. 413 



place, in the form of a stellate, crystalline mass. By 

 maceration with ether and subsequent recrystallization 

 from alcohol it is freed of fatty oil. 



Properties. Crystallized from alcohol, it forms color- 

 less, fine crystalline scales, of a pearly lustre, with- 

 out odor, of a slightly bitter taste. Easily soluble 

 in water, from which it crystallizes in large, trans- 

 parent prisms with three molecules of water. Not 

 volatile. When heated with acetic anhydride, it is con- 

 verted into heptacetijl-amygdalin, C 20 H 20 N0 4 (O.C 2 H 3 0) 7 , 

 which crystallizes in long needles, of a silky lustre, 

 insoluble in water, soluble in alcohol and ether. 



Decompositions. It is resolved by treatment with 

 dilute acids, or when in contact with emulsin (an 

 albuminous body contained in almonds) into sugar, 

 hydrocyanic acid, and oil of Utter almonds (p. 317), two 

 molecules of water being taken up. Boiled with 

 potassium or barium hydroxide, it is decomposed, 

 forming ammonia and a white, crystalline, deliquescent 

 acid, amygdalic acid, C 20 H 28 13 . 



2. Solanin. 



Occurrence. In the various species of Solanum, par- 

 ticularly in the young sprouts of old potatoes. 



Preparation. Potato sprouts are macerated with 

 water containing a little sulphuric acid, the quickly 

 filtered solution mixed warm with ammonia, the pre- 

 cipitate filtered off* after prolonged standing, thoroughly 

 dried, and repeatedly boiled with alcohol. On the 

 cooling of the boiling-hot filtered solution, the greater 

 part of the solanin separates, and, by recrystallization 

 from alcohol, is now thoroughly purified. 



Properties. Fine prisms, of a silky lustre, almost 

 insoluble in water, but slightly soluble in cold alcohol, 

 more easily in hot ; fuses at 235. Acts poisonously. It 

 is a weak base, possesses a weak alkaline reaction, dis- 

 solves readily in acids, and yields with them gummy, 

 uncrystalline salts, which can be precipitated from 

 their solutions in alcohol by ether. 



