OP ARTS AND SCIENCES. 33 



Oxidation of methyluric acid with nitric acid. 



By the oxidation of methyluric acid with nitric acid, a solution is 

 obtained which gives a deep red coloration on wanning with amnionic 

 hydrate. From this solution, however, I have as yet been unable to 

 isolate a crystalline product. By spontaneous evaporation in the air, 

 a sticky syrup is obtained, which does not solidify, even after long 

 standing in vacuo over sulphuric acid. Alcohol dissolves this residue, 

 the solution remains clear after the addition of ether, and on evaporation 

 again leaves an uncrystallizable syrup. I have been equally unsuccess- 

 ful in separating by stannous chloride or sulphide of hydrogen a 

 crystalline alloxantine or dialuric acid. Oxidation with potassic 

 chlorate and hydrochloric acid, according to the method of Schlieper,* 

 gave the same result. These reactions were sufficient to give a quali- 

 tative proof tliat the solution did not contain ordinary alloxan. I 

 therefore attem(»ted to prepare from this solution a methylalloxanate 

 in form fit for analysis. I first tried with baric hydrate, to form the 

 barium salt. The ordinary method, following closely the directions 

 of Schlieper, f gave me, however, a salt containing but a trace of 

 nitrogen and with percentages of barium, carbon, and hydrogen, 

 closely approximating those required by a basic baric mesoxalate, 

 BaCgO^.BaO^H^. At the same time a strong smell of methylamine 

 was perceived. If a smaller quantity of baric hydrate were added in 

 the cold, and then alcohol in excess, a barium salt was thrown down 

 which contained nitrogen, but it could not in this way be obtained of 

 constant cumposition. Plumbic hydrate seemed to determine the for^ 

 mation of the methylalloxanate, but no better results were obtained. 

 The silver salt blackened too rapidly to admit of analysis. 



The lime salt is the only one I have been able to prepare with con- 

 stant composition. Methyluric acid is dissolved in as small a quantity 

 of nitric acid of 1.42 sp. gr. as possible, the solution somewliat diluted, 

 and the excess of acid neutralized with calcic carbonate in the cold. 

 The solution is tiien allowed to stand in vacuo for some time, to free it 

 from carbonic dioxide, afterwards diluted with six or eight volumes of 

 alcohol and filtered. The cautious addition of amnionic hydrate to 

 the filtrate throws down a bulky semigelatinous precipitate, wiiich, well 

 washed with alcohol, and dried at 100°, forms an amorphous powder, 

 which has a faint pink color, — undoubtedly caused by a trace of alloxan. 

 The dry salt was soluble in cold water, though with some difficulty. 



* Ann. Cliem. u. Pharm. 55, 2G1. 

 t Ann. Chem. u. Pharui. 55, 212. 

 TOL. XII. (n. S. IV.) 3 



