ALKALOIDS. 605 



Sparteine sulphate, Ci 5 H 26 N. 2 H 2 S0 4 + 5H 2 0, is obtained by saturating the 

 alkaloid with sulphuric acid ; it is a colorless, crystalline salt, readily soluble 

 in water. An ethereal solution of the salt, to which a few drops of ammonia 

 water have been added, deposits, on the addition of an ethereal solution of 

 iodine, minute dark greenish-brown crystals. 



The tropine group of alkaloids. 



Atropine, Atropina, C^H^NOs = 287.O4 (Daturine). Obtained 

 from Atropa belladonna. It is a white, crystalline powder, having a 

 bitter and acrid taste and an alkaline reaction ; it is sparingly soluble 

 in water, but very soluble in alcohol and chloroform. The commer- 

 cial article generally contains a small quantity of hyoscyamine. 

 Atropine sulphate, (CtfH^NO^.ELjSO^ is a white, crystalline powder, 

 easily soluble in water. 



Analytical reactions : 



1. Atropine dissolves in concentrated sulphuric acid without color. 

 This solution is not colored by nitric acid (difference from morphine), 

 and not at once by potassium dichromate (difference from strychnine). 

 " 2. A mixture of atropine and nitric acid, when evaporated to dry- 

 ness over a water-bath, leaves a yellow residue, which turns violet on 

 the addition of a few drops of an alcoholic solution of potassium 

 hydroxide and a fragment of the same reagent. 



3. On warming a mixture of atropine and concentrated sulphuric 

 acid a pleasant odor, reminding of roses and orange flowers is evolved. 

 The addition of a few fragments of potassium dichromate changes 

 this odor to that of bitter almond. 



4. Solutions of atropine dilate the pupil of the eye to a marked 

 extent. 



Homatropine, C 16 H 21 NO 3 . This alkaloid is obtained by the con- 

 densation of tropine and mandelic acid. The hydrobromide is offi- 

 cial. It is a white crystalline powder, and resembles atropine in its 

 mydriatic properties. 



Hyoscyamine, C 17 H 23 NO 3 . Found in small quantities together 

 with hyoscine in the seeds of Hyoscyamus niger (henbane), and in 

 some other plants belonging to the solanaceae. 



Hyoscyamine resembles atropine closely in most of its chemical, 

 physical, and physiological properties, but the corresponding salts of 

 the two alkaloids crystallize in different forms ; the hydrobromide and 

 sulphate are official. 



