U>9 



Tlie substance of Grimaux shows biuret reaction and, after being- 

 dissolved in dilute potassium hydroxide solution evolves ammonia in 

 the cold and yields on acidifying with acetic acid a crj'stalline 

 precipitate. 



In the Berichte der Deutschen chemischen Gesellschaft 46 p. 1404, 

 H. BiLTz and E. Topp discuss this oxalyldiureid 



CO NH CO NH, 



CO NH CO NH„ 



obtained by the interaction of oxaljlchloride with uiea and con- 

 sider this identical with the "amide d'un acide oxalylbiurétique" 



CO NH, 



I of Grimaux. I have now tried to prepare this 



CO NH CO NH CO NH, 



compound synthetically in order to be able to show that this substance 

 is different from the true oxalyldiureid. 



As has been shown previously, on boiling in dry benzene there 

 are formed in the interactionof oxalylchloride with amides and with 

 similar substances possessing a primary amide function, in most 

 cases the corresponding carbonyl derivatives. On the ground of this 

 experience it was to be expected that, if we allow in the same 

 manner oxaminic acid ethylester and ethyl nrethane to react in 

 equimolecular quantities a substance might form of the composition 



CO OC, H, 



I which might be called a. carbeihoxyl 



CO NH . CO . NH COO (\ H, 



b. oxalylethoxyl urea. This substance indeed formed to the extent 

 of 107o of the theoretical quantity in the presence of other products 

 and after repeated recrystallisations from dry ethyl acetate it crystal- 

 lised in beautiful glittering needles melting at 152°, the analyses 

 of which were quite in accordance with the theoretical results. 



It could not be recrystallised from water as this causes a decom- 

 position to set in with formation of oxaluric acid. 



When this substance was dissolved in absolute alcohol and a 

 current of dry gaseous ammonia passed through the solution while 

 cooling in ice, a fine pulverulent substance was deposited which on 

 account of its mode of formation and analysis could be considered 

 to be the amido-oxalylbiuret and in properties agreed entirely with 

 the "amide d'un acide oxalylbiurétique" of Grimaux. 



This amido-oxalylbiuret also showed the so-called biuret reaction, 

 dissolved in alkali with evolution of ammonia and then gave with 

 acetic acid a crystalline precipitate either as stated by Ponomarew 



