MUREXANE. . 



cipitate, which becomes yellow on boiling, without dissolving. 

 In this respect it agrees with a solution of alloxane mixed with 

 ammonia. 



If we decompose murexide by muriatic acid, separate the mu- 

 rexane, and add barytes water to the acid liquid, a dense preci- 

 pitate falls of a light violet colour. This reaction indicates the 

 presence of alloxantin. The precipitate is not of so deep a vio- 

 let as with pure alloxantin, but it is not colourless like that from 

 pure alloxane. A current of sulphuretted hydrogen instantly 

 destroys the colour of the murexide. Silky plates of murexane 

 precipitate ; and the liquid gives with barytes water a deep vio- 

 let precipitate, while ammonia is disengaged. It is obvious that 

 the alloxane become free is changed by the sulphuretted hydro- 

 gen into alloxantin. 



When we boil murexide with a solution of potash till the deep 

 indigo blue colour disappear, precipitate the murexane by mu- 

 riatic acid, and neutralize the liquid exactly with ammonia, it 

 does not precipitate the salts of lime and barytes. But if we add 

 a new dose of ammonia, dense white flocks fall, which disappear 

 when we add a large quantity of water. This reaction charac- 

 terizes the alloxanates of lime and barytes. 



If, after having decomposed murexide by dilute sulphuric acid, 

 we pour barytes water into the cold liquid, as long' as a precipi- 

 tate continues to fall, the whole sulphuric acid, and along with 

 it all the alloxane and alloxantin, except a mere trace, are pre- 

 cipitated. The filtered solutions being treated with carbonate of 

 ammonia to separate the free barytes, filtered anew, and evapo- 

 rated to a small bulk, gives with nitric acid crystals of nitrate of 

 urea. 



The solution obtained by the decomposition of murexide by 

 means of sulphuric acid being neutralized by carbonate of am- 

 monia, and evaporated in a very gentle heat, loses, after some 

 time, the red colour which it had assumed. It gives a crystal- 

 line mass, in which it is easy to recognize alloxanate of ammonia 

 mixed with sulphate. The same solution being treated with am- 

 monia and a salt of silver, gives a white precipitate, which, by 

 the action of a gentle heat, becomes black while gas is disengaged, 

 and is reduced to metallic silver. 



From all these reactions, it results that murexide produces, by 

 its decompositions by acids and alkalies, five different products, 



