208 LEUKOMAINES. 



have the constitution of tetramethylen-diamine NH 2 (CH 2 ) 4 lSrH 2 . They 

 have both recently been obtained as conspicuous constituents of urine 

 from a case of cystinuria and appear to owe their origin to putre- 

 factive processes occurring in the intestine 1 . They are both somewhat 

 viscid fluids which crystallise at low temperatures, and yield readily 

 crystallisable compounds with acids and salts of gold, platinum and 

 mercury. Their benzoyl compounds are insoluble in water and hence 

 afford a convenient means for their separation. Cholin and the highly 

 toxic neurin, which really belong to this class, have already been 

 described. (See above pp. 136, 137.) 



Leukomaines. This name has been applied by Gautier 2 to those 

 basic (alkaloidal) substances which occur in living tissues and are to be 

 regarded as products of their normal metabolism and thus distinct 

 from ptomaines. They are obtained by extracting finely minced ox-flesh 

 with an extremely dilute aqueous solution of oxalic acid. According 

 to Gautier this extract may contain the following six bases : Xantho- 

 kreatinin, C 5 H 10 N 4 O; Chrysokreatinin, C 5 H 8 N 4 O ; Amphikreatinin, 

 C 8 H 19 N 7 O 4 ; Pseudoxanthin, C 4 H 5 ]Sr 5 O and two, as yet unnamed, with 

 the composition C 11 H 24 N 10 O 5 and C 12 H 25 N n 5 respectively. They 

 probably stand in close relationship to paraxanthin, C 7 H 8 N 4 O 2 , 

 heteroxanthin, C 6 H 6 N 4 O 2 and adenin C 5 H 5 N 5 (see above p. 182), and 

 it is interesting to note that comparing the formulae of the leukomaines 

 with each other and with those of kreatinin C 4 H 7 N 3 O and kreatin 

 C 4 H 9 N 3 2 they are found to differ in several cases by the group CflSTH. 



The leukomaines are regarded by Gautier as feebly toxic alkaloidal 

 products of metabolism from which the organism is normally freed 

 either by their excretion, since .they are found in urine (see above), or 

 by destructive oxidation, and it has further been suggested that their 

 abnormal retention in the economy may be the cause of certain* obscure 

 pathological conditions 3 . 



THE BILE-ACIDS. 



1. Cholalic (or cholic) acid. C 24 H 40 5 . 



To avoid confusion the term ' cholic ' should be in all cases used as synonymous 

 with 'cholalic.' Demarcay who first described cholalic acid as a product of the 

 decomposition of bile-acids gave it the name of cholic acid 4 . The name cholalic 



1 Udranszky u. Baumann, loc. cit. See also Stadthagen u. Brieger, Virchow's 

 Arch. Bd. cxv.'(1889), S. 490. 



2 Sur les alcaloides derives de la destruction bacterienne ou physiologique des 

 tissus animaux. Paris, 1886. Bull, de Vacad. de med. Jan. 12, 19, 188C. The name 

 is derived from XeuKu/m, occasionally used to denote white of egg and hence to 

 indicate their origin from proteids. 



3 cf. Bouchard, Compt. Rend. T. en. (1886), pp. 669, 727, 1127. 



4 Liebig's Ann. Bd. xxvii. (1838), S. 270. 



