552 AN AMERICAN TEXT-BOOK OF PHYSIOLOGY. 



Diamido-valeric Acid, or Ornithin, C 4 H T ( XH 2 ) 2 COOH. — This has been detected by 

 Jaffe in the urine and excrements of fowls. 



«-£-Diamido-caproic Acid, or Lysin, CII 2 XII,CH 2 CH 2 CH 2 CHNH 2 - 

 COOH. — This is a hydrolytic cleavage product of proteid after boiling with 

 hydrochloric acid, or baryta water, 1 and may be similarly obtained from gela- 

 tin, from vegetable proteid (eonglutin), from the pancreatic digestion of 

 proteid, and from the decomposition of the protamine. Other bases are: 



Histidin, ( ,II ( N\()„ a base derived from all proteids and from protamins. 



/NH 2 

 Arginin, 2 CNHC 



\\H — CH 2 — CH 2 — CH 2 — CHNH 2 COOH, is also 

 derived from all proteids and from protamins. 



PURIN OR ALLOXURIC BODIES AND BASES. 



The alloxnric bodies comprise those containing in combination two radicals, 

 one of alloxan, OC < xtu f v \ > CO, the other of urea. The skeletal struc- 

 ture of all alloxuric bodies may be written thus : 



These bodies fall into three groups, that of hypoxanthin, of xanthin, and of 

 uric acid. Bodies belonging to the first two groups are called alloxuric bases, 

 or more commonly xanthin bases, or nuclei n bases, because they are derived 

 from nucleiu. The strong family analogy of the three groups is shown by 

 the following reactions — results of heating with hydrochloric acid in sealed 

 tubes at 180° to 200° : 3 



C 5 H 4 N 4 + 7H 2 = 3NH 3 + C 2 H 5 M) 2 + C0 2 + 20H 2 O 2 . 



Hypoxanthin. Glycocoll. Formic acid. 



5 H 4 N 4 O 2 + 6H 2 = 3NH 3 + C 2 H 6 N0 2 + 2C0 2 + CH 2 2 . 



Xanthin. 



C 5 H 4 N 4 3 + 5H 2 = 3NH 3 + C 2 H 5 N0 2 + 3C0 2 . 



Uric acid. 



Reference to the formulae below will show that the molecules of C0 2 given 

 off correspond t<» the number of CO radicals in the alloxuric body, while the 

 molecules of formic acid correspond to the number of CH groups. 



Emil Fisher 4 has discovered a body called purin, and has given another 

 classification. The chemical series of the purin bodies may thus be presented : 



1 Drechsel: Archiv far Physiologie, 1891, S. 248. 



• Formula by Schulze and Winterstein : Zeitechrift far physiologische Chemie, 1899, Bd. 26, 

 S. 12. 



s Kriiger: Ibid., 1894, Bd., 18, S. 463. 



* Berichte der deuUchen ehetnisrlicn <;,.« //,«■/, aft, 1899, Bd. 32, S. 435. 



