786 URINE. . 



into a conjugated glucuronic acid, uronitrotoluolic acid (JAFFE 1 ). The 

 glucuronic acid split off from this conjugated acid is levogyrate and hence 

 is not identical, but only isomeric, with the ordinary glucuronic acid. 

 Dimethylaminobenzaldehyde, according to JAFFE, is converted in part 

 into dimethylaminobenzoglucuronic acid in rabbits. The same conjugated 

 glucuronic acid is also produced, according to HiLDEBRANDT, 2 from p- 

 dimethyltoluidine, which is first changed into p-dimethylaminobenzoic 

 acid. Indol and skatol seem, as above stated (page 731), to be eliminated 

 in the urine partly as conjugated glucuronic acids. The mercapturic 

 acids, which will be mentioned below, also belong to those substances 

 which are conjugated with glucuronic acid, and after this conjugation 

 appear in the urine. 



A conjugation of carbamic acid, NEbCOOH, with amino-acids to form 

 uramino-acids, R.CH.NH.(CONH 2 )COOH, or their anhydrides, the 

 hydantoins, have also been observed in several cases, as after feeding 

 sarcosin, amino-benzoic acid, phenylalanine, taurine, tyrosine. It must 

 be remarked that according to LIPPICH and DAKIN, S the uramino-acids 

 can be easily produced as transformation products from the urea in the 

 concentration of the urine by the aid of heat. 



Syntheses with a simultaneous acetylation are of great interest. 

 Such a synthesis is the formation of the mercapturic acids. These acids, 

 which are produced in the body of dogs after the introduction of brom- 

 and chlorbenzene (BAUMANN and PREUSSE, JAFFE, FniEDMANN 4 ) are 

 acetylated derivatives of the protein cystine, and the acetylated brom- 

 phenylcysteine is CH 2 .S (C 6 H 4 Br) .CH.NH(COCH 3 ) .COOH. Another 

 example of a synthesis with acetylation is the phenylaminoacetic acid, 

 which, as NEUBAUER and WARBURG 5 have shown, in perfusion exper- 

 iments with dog's livers, gives among other products also acetylated 

 phenylaminoacetic acid, C 6 H 5 .CHNH(COCH 3 ).COOH. 



The synthesis of amino-acids, with simultaneous acetylation, as 

 recently observed by KNOOP, are of specially great interest. After the 

 introduction of 7-phenyl-a-keto butyric acid into the body of a dog, 

 the formation of the corresponding acetylated amino-acid, 



C 6 H5.CH2.CH2.CHNH(COCH 3 ).COOH 



1 Zeitschr. f. physiol. Chem., 2. 



2 Jaffe", Zeitschr. f. physiol. Chem., 43; Hildebrandt, Hofmeister's Beitrage, 7. 



3 Lippich, Ber. d. d. chem. Gesellsch., 41; Dakin, Journ. of biol. Chem., 8; Weiland, 

 Bioch. Zeitschr., 38. 



4 Baumann and Preusse, Zeitschr. f. physiol. Chem., 5; Jaffe", Ber. d. deutsch. 

 chem. Gesellsch., 12; Friedmann, Hofmeister's Beitrage, 4. 



6 Neubauer and O. Warburg, Zeitschr. f. physiol. Chem., 70. 



