784 URINE. 



nitrogroup is also reduced to an amino-group, and finally acetic acid 

 attaches itself to this with the expulsion of water, so that the final product 

 is m-acetylaminobenzoic acid, (CHs.COXNH.CeH^COOH. The p-nitro- 

 benzaldehyde acts in rabbits in part like the ra-aldehyde and passes in 

 part into p-acetylaminobenzoic add. Another part is converted into 

 p-nitrobenzoic acid, and the urine contains a chemical combination of 

 equal parts of these two acids. According to SIEBER and SMIRNOW p- 

 nitrobenzaldehyde yields only urea p-nitrohippurate in dogs. The above- 

 mentioned pyridine-carboxylic acid, formed from methylpyridine 

 (a-picoline) passes into the urine after conjugation with glycocoll as 

 a-pyridinuric acid. 1 



To those substances which undergo a conjugation with glycocoll 

 belongs also furfural (the aldehyde of pyromucic acid, C^sO.CHO), 

 which, when introduced into rabbits and dogs, as shown first by JAFFE 

 and CoHN, 2 and then further shown by SASAKI and FRIEDMANN, is elimi- 

 nated in two ways from the body. The furfurol can, by a similar synthesis 

 to PERKIN'S reaction, be transformed into the unsaturated Sicidfurfuracrylic 

 acid C 4 H 3 O.CH:CH.COOH, and also into pyromucic acid C 4 H 3 O.COOH. 

 These two acids pass, after conjugation with glycocoll, into the urine as 

 furfuracryluric acid and pyromucuric acid. In birds the pyromucic acid 

 is conjugated with ornithine and is eliminated as pyromucinornithuric acid. 



It has not been proved how thiophene, C4H 4 S, behaves in the animal 

 body. Of methylthiophene (thiotolene), C^aS.CHs, a very small part is 

 oxidized to thiophenic acid, C^aS.COOH (LEVY). This acid, as shown 

 by JAFFE and LEVY, S is conjugated with glycocoll in the body (rabbits) 

 and eliminated as thiophenuric acid. 



Another very important synthesis of aromatic substances is that of 

 the ethereal-sulphuric acids. Phenols, and in particular the hydroxylated 

 aromatic hydrocarbons and their derivatives are voided as ethereal-sul- 

 phuric acids, according to BAUMANN, HERTER and others. 4 



A conjugation of aromatic acids with sulphuric acid occurs less often. 

 The two previously mentioned aromatic acids, p-oxyphenylacetic and 

 p-oxyphenylpropionic acid, are in part eliminated in this form. Gentisic 

 acid (hydroquinone-carboxylic acid) also increases, according to LIK- 

 HATSCHEFF, 5 the quantity of ethereal-sulphuric acid in the urine, while 



1 In regard to the extensive literature on glycocoll conjugations we refer the reader 

 to O. Kuhling, Ueber Stoffwechselprodukte aromatischer Korper. Inaug.-Diss., 

 Berlin, 1887. 



2 Ber. d.d. Chem. Gesellsch., 20 and 21; Sasaki and Friedmann, footnote 1, page 782. 



3 Levy, Ueber das Verhalten einiger Thiophenderivate, etc., Inaug.-Diss., Konigs- 

 berg, 1889; Jaffe and Levy, Ber. d. d. chem. Gesellsch., 21. 



4 In regard to the literature, see O. Kuhling, 1. c. 

 6 Zeitschr. f. physiol. Chem., 21. 



