140 BASIC BODIES. 



CREATININE. C 8 H^N 3 O 2 . 

 Chemical Relations. 



Properties. This alkaloid forms colourless, very glistening 

 crystals, belonging to the monoclinometric system : has almost as 

 burning a taste as caustic ammonia, dissolves in 11 '5 parts of water 

 at an ordinary temperature, but more readily in hot water ; while 

 it requires about 100 parts of cold spirit to dissolve 1 part of crea- 

 tinine, it is so freely soluble in hot spirit that, on cooling, it again 

 separates in crystalline masses ; it is also slightly soluble in ether ; 

 it shows a strong alkaline action on vegetable colours, and it even 

 separates ammonia from its salts. A moderately concentrated 

 solution of nitrate of silver added to a solution of creati- 

 nine, causes a coagulation into a net-work of acicular crystals, 

 which dissolve on being boiled with water, and again appear when 

 it cools. A solution of corrosive sublimate yields a curdy preci- 

 pitate, which soon becomes crystalline; chloride of zinc likewise 

 forms a crystalline granular precipitate. Bichloride of platinum, 

 however, yields no precipitate when the solution is somewhat 

 dilute. 



Composition. We are indebted solely to Liebig* for our 

 knowledge of the composition of this substance. From the analyses 

 of its salts he deduced the above formula, according to which it 

 consists of: 



Carbon 8 atoms .... 42'48 



Hydrogen 7 .... 6'19 



Nitrogen 3 .... 37'17 



Oxygen 2 .... 14'16 



100-00 



Its atomic weight 1412-5. As this body possesses such strong 

 basic properties, we may accept the hypothesis of Berzelius regarding 

 its theoretical composition as the most probable one, namely, that 

 it is ammonia conjugated with a highly nitrogenous body, con tain- 

 ing exactly 1 atom less of hydrogen than caffeinerr H 3 N.C 8 H 4 N. 2 O 2 . 

 Moreover, a comparison of the formulae shows that creatinine con- 

 tains exactly 2 atoms of water less than anhydrous creatine. 



Combinations. The combinations of creatinine with acids are, 

 as far as is yet known, soluble in water and readily crystallisable. 



Hydrocldorate of creatinine, K.HC1, crystallises from hot alcohol 

 * Ann. d. Ch. u. Pharm. Bd. 62, S. 257-290. 



