OBNITHIN. 4:i7 



after administration of benzoic acid. This acid as pointed out on 

 p. 437 is a di-benzoyl compound of ornithin and yields the base on 

 cleavage with concentrated acid. Ornithin therefore can be looked 

 upon as an intermediate waste product (and possibly as an uric 

 acid antecedent) in the chicken just as glycocoll is such in other ani- 

 mals. The base, however, is by no means peculiar to the chicken, 

 inasmuch as it exists preformed in arginin which, as pointed out 

 (p. 426), is present in all proteid matter, whether of animal or plant 

 origin. The partial synthesis of arginin from ornithin and cyanamid 

 has been referred to. Ornithin can be prepared readily from arginin.' 



The belief of Jaff6 that ornithin was a di-amido valerianic acid has 

 been definitely established in the past year or two. The cleavage of 

 arginin into urea and ornithin and the decomposition of the latter by 

 bacteria into putrescin demonstrate that this peculiar base is a-d 

 diamine valerianic acid (p. 438). 



The synthesis of a-8 diamine valerianic acid has only recently 

 been effected by Fischer.' It yields with benzoyl chlorid a di-ben- 

 zoyl derivative, C,gHj(,NjO^, which is strikingly similar to ornithuric 

 acid. While the latter melts at 182° (Jaff6), 184° (Schulze and 

 Winterstein), the synthetic product melts at 184°- 185°. The syn- 

 thetic and natural ornithuric acids yield the same characteristic cal- 

 cium salt, (CjjHjgNjOJjCa. They both, on partial cleavage, form 

 the mono-benzoyl derivative, which in the case of the natural base 

 crystallizes in needles (JaffI), whereas the synthetic body forms plates. 



The synthetic ornithin is strongly alkaline in reaction, gives a 

 flocculent white precipitate with mercuric chlorid and in acid solu- 

 tion gives with phosphotungstic acid a heavy crystalline precipitate 

 which easily dissolves on heating and reappears on cooling in color- 

 less needles. The only real difference between the synthetic and 

 natural ornithin is in the fact that the latter is dextro-rotatory, while 

 the former is inactive. The synthetic ornithin is therefore the racemic 

 form of the natural base as obtained from chicken and from arginin. 

 The properties of the base and of several of its salts have been de- 

 scribed by Schulze and Winterstein.' Like lysin it unites with 

 phenyl isocyanate to form an addition product which with hydro- 

 chloric acid yields an easily crystallizable hydantoin (Herzog*). 



Ornithin on cleavage by bacteria yields putrescin and it is very 

 probable that this change may be effected by chemical means and 

 also by metabolism within the body. Indeed Lawrow's* studies 

 upon the auto-digestion of pig's stomachs show that pepsin may 

 split up proteids into monamido acids and the diamins — cadaverin and 

 putrescin. The occurrence of these bases in cystinuria may be ac- 



' Zeits. phyM. Chem., 34, 525. 

 'Berkhte, 34,454(1901). 

 ' Zeits. phyml. Chem., 34, 128. 

 * Zeits. physiol. Chem., 34, 525. 

 ^ Zeits. physiol. Chem., 33, 312. 



