374 CHEMISTRY OF THE LEUGOMAINS. 



On heating brom-hypoxanthin with sodium carbonate, or by pass- 

 ing carbonic acid into a solution of the base in sodium hydrate, the 

 sodium compound of brom-hypoxanthin forms, CgH^NaBrN^O + 

 2HjO. It is easily soluble in hot water ; rather difficultly in cold 

 water. The solution has an alkaline reaction. The free base can 

 be obtained by adding the calculated quantity of acid. The corre- 

 sponding barium compound is obtained by passing carbonic acid 

 into a solution of brom-hypoxanthin in barium hydrate. On con- 

 centration it crystallizes in fine white needles, and has the compo- 

 sition (C5H2BrN^O)jBa. The lead compound forms, on the addition 

 of lead acetate to a solution of the base in sodium hydrate, as an 

 amorphous precipitate. 



The bromin in brom-hypoxanthin is held as firmly as that in brom- 

 adenin. Thus it is not affected by heating with alcoholic potash for 

 three hours. 



On decomposition of brom-hypoxanthin with hydrochloric acid 

 and potassium chlorate Kriiger obtained alloxan and urea. The 

 yield of alloxan is not greater than that from adenin, and much less 

 than that from xanthin, due undoubtedly to the alloxan nucleus 

 splitting up into simpler bodies because of a different arrangement 

 of bonds. 



The synthetic dichlorhypoxanthin was prepared by Fischer from 

 trichlorpurin (p. 337). 



Benzyl hypoxanthin, CjHjN^O.CHj.CjHj, was obtained by Thoiss 

 by the action of nitrous acid on benzyl adenin. It forms a white 

 crystalline mass which under the microscope consists of thin plates. 

 It is easily soluble in hot water, dilute alcohol, and in acetic ether ; 

 insoluble in ether and chloroform. It melts at 280°. It appears, 

 as Kossel pointed out, that adenin and hypoxanthin con^in a 

 group, CjH^N^, which he named adenyl. This, it will be seen, cor- 

 responds to Fischer's purin. 



Two of the possible 3-methyl hypoxan thins are known. The 7- 

 and 9-methyl derivatives can be prepared from the corresponding 

 compounds of adenin by the action of nitrous acid (Fischer).* 



1-7-dimethyl hypoxanthin, C5H2(CH3)jN^O. This compound was 

 prepared by Bruhns, in the same way as methyl adenin, by heating 

 hypoxanthin with alcohol, sodium alcoholate, and methyl iodid. 

 Fischer ^ prepared the same derivative from dichlorhypoxanthin and 

 from 7-methyl hypoxanthin. A compound of dimethyl hypoxanthin 

 with sodium iodid, C5Hj(CH3)2Np.NaI -|- SHp, formed first which, 

 crystallized from alcohol, gave prismatic crystals, easily soluble in 

 water and in hot alcohol, insoluble in ether. The synthetic hy- 

 poxanthin forms this same characteristic double salt. Other bases 

 of the uric acid group are not known to form similar compounds. 



^Berichte, 30, 2409 ; 31, 113. 

 « SericMe, 30, 2230, 2411. 



