124 CHEMISTRY OF THE PROTEIDS CHAP. 



this reaction illustrates therefore the transition of a dibasic mono- 

 amino-acid into a mono-basic diamino-acid. 



Hippuryl-aspartic-acid-azide + alcohol forms the normal urethane : 



C 6 H 5 CO . NHCH 2 CO . NHCHNH . CO . 00 2 H 5 



CH 2 NH . CO . OC 2 H 5 . 



This compound by taking up four molecules of water gives rise, in 

 addition to hippuric acid, ammonia, C0 2 , and "alcohol, to amino- 

 acetaldehyde : 



C r H,CO . NHCH 2 CO . NHCHNH . CO . OCJL 



I + 4H 2 = 



CH 2 NH . CO . OC 2 H 5 

 C 6 H 5 CO . NHCH 2 COOH + 2NH 3 + NH 2 CH 2 CHO + 2C0 2 + 2C 2 H 6 OH. 



This reaction is complementary to the last one, for by it a dibasic amino- 

 acid is converted into the aldehyde of the monobasic glycocoll. 



Gumlich has in addition shown that the urethane, formed by 

 boiling hippuryl-/2-amino - butyric-acid - azide with alcohol, on being 

 hydrolysed, jaelds in addition to benzoic acid, glycocoll, C0 2 , and 

 alcohol, also propylenediamin. Out of a molecule of a substituted 

 /3-amino-butyric acid there is formed in this way a dibasic acid of the 

 ethylene-diamin series. 



Curtius points out the great interest of the conversion of glycocoll 

 and other ammo-acids into complex urea-like bodies which, on hydro- 

 lysis, yield partly formaldehyde and its homologues, and partly amino- 

 aldehydes. " The transformation of dibasic mono-amino-acids to mono- 

 basic diamino-acids and the formation of a diamin of the putrescin-type 

 from a monobasic mono-amino acid, opens up new, far-reaching vistas, 

 for do we not see a number of substances, such as formaldehyde, which 

 are of importance for the synthetic processes in organisms, and also 

 others such as diamino-acids which are formed during the hydrolysis of 

 albumins, stand in relatively simple genetic relationship to the various 

 mono-amino acids, and do we not meet with bodies identical with those 

 which are formed during the putrefaction of albuminous compounds." 



Schiitzenberger l combined leucin and leuceine with urea by heating 

 with phosphoric acid anhydride, and so obtained colloidal compounds. 



Balbiano and Frasciatti 2 converted glycocoll by heating with 



1 P. Schiitzenberger, " Kecherches sur la synthese des matieres albuminoides et pro- 

 teiques," Compt. Rend. 106. 1407 (1888) and 112. 198. (1891). 



2 Balbiano and Frasciatti, Ber. d. deutsch. chem. Ges. 33. 2323 (1900) ; and 

 Balbiano, ibid. 34. 1501 (1900). 



