ACETYLIZING PROCESSES 475 



Fixation of acetic acid to aminobenzoic-acid. 



NH(CO.CH.) 



has been previously mentioned. It seems too that the mer- 

 capturic acids (studied by Baumann and by E. Friedmann), 

 which are met in the urine of dogs to which iodobenzol or 

 bromobenzol has been administered, owe their origin to the 

 simultaneous combination of cystein with halogenbenzol and 

 with acetic acid : 55 



/von BROMO- ACETIC BROMOPHENYLMERCAPTTJRIC 



BENZOL ACID ACID 



CH 2 .SH 



CH.NH 2 . -f CoHsBr + CH,.COOH - > CH.NH.(CO.CH) 



COOH COOH. 



In addition, 0. Neubauer 56 and his collaborators have 

 obtained both in the artificially perfused liver of the dog, 

 and, too, under the influence of fermenting yeasts from 



djHff CH.COOH 

 phenylaminoacetic acid, (besides phenylgly- 



NH 2 



f TT OTT f"*OOTT 



oxylic acid, C 6 H 5 .CO.COOH, and amygdalic acid, ' ' I ) 



CcHr-CH.COOH 



acetylphenylammoacetio acid, . Knoop, 57 



NHCCO.CH,) 



too, found that a portion of phenylaminobutyric acid, 



, introduced into the system is excreted 



CH 2 .CH,.CH(NH 2 ) .COOK 



as acetyl-derivative. It seems, therefore, that a rather wide 

 distribution is to be recognized for acetylization in the econ- 

 omy. Knoop points out a very striking coincidence between 

 this process and the catabolism of aminoacids from the point 

 of view of a transposition described by the younger Erlen- 

 meyer and van de Jong, in which two molecules of racemic 



66 E. Friedmann (F. Hofmeister's Lab.), Hofmeister's Beitr., 4, 486, 1903. 

 86 O. Neubauer, in association with 0. Warburg and K. Fromherz (F. v. 

 Mtiller's Clinic, Munich), Zeitschr. f. physiol. Chem., 70, 252, 325, 1911. 

 57 F. Knoop and E. Kertess, 1. c. 



