312 VII, ACIDS, AMIDES, ALDEHYDES AND HYDROCARBONS 



and jS-n-decyladipic acid, practically completely utilized. Emmrich^^ 

 obtained almost identical results on feeding (S-methyladipic acid to dogs. 

 The increased tolerance obtained on lengthening the alkyl residue was like- 

 wise reported by Bernhard for alkylmalonates^^ and by Emmrich et al}^ 

 and Bernhard and Lincke^'' for alkylsuccinates. The tolerance values ob- 

 tained by the former investigators^^ for alkylsuccinates were as follows: 

 methylsuccinic acid, 0.35 g. ; ethylsuccinic acid, 0.23 g. ; n-propylsuccinic 

 acid, 0.09 g. ; n-butylsuccinic acid, 0.09 g. ; and n-hexylsuccinic acid, 

 0.09 g. When the dicarboxylic acids having long-chain alkyl residues are 

 fed, tricarboxylic acids can be detected, presumably as a result of co- 

 oxidation of the alkyl substituent. Such phenomena have been ob- 

 served after octyl-, nonyl-, or decylmalonate*^ or nonyl- or decylsuccinate^" 

 has been fed. After the feeding of nonylsuccinate, HOOC-CH((CH2)8-- 

 CH3) • CH.2 • COOH, the side chain was shortened three times by |8-oxida- 

 tion of the side chain after co-oxidation; 



i8-carbo.xy-7-o.\yadipic acid, 



COOH 

 HOOC • CH2 • CO • C • CH.2 ■ COOH 



was isolated from the urine. 



According to Flaschentriiger," the several dicarboxylic acids were ex- 

 creted in the urine unchanged by dogs in the following proportions after 

 they had been injected: adipic, 40%; suberic, 60%; and sebacic, 61%. 

 After the injection of each of the several Ce to Cio dicarboxylic acids into 

 phlorhizinized dogs, Baer and Blum^^ reported the following recoveries: 

 adipic, 12%; pimelic, 47%; suberic, 62%; azelaic, 50%; and sebacic, 

 46 and 13.7%. Although the figures for the extent of diaciduria are 

 probably of little importance, since they would be expected to vary with 

 the size of the dose administered, they do indicate that the tolerance for all 

 these acids is exceedingly low. Rose^^'^^ noted that adipic, pimelic, suberic, 

 and azelaic acids produce a nephritis in rabbits qualitatively similar to 

 that caused by glutaric and by tartaric acids; however, quantitatively, 

 the extent of the nephritis was less severe when the higher dicarboxylic 

 acids were given than following the shorter-chain dicarboxylic acids. 

 Mucic acid (HOOC •(CH0H)4- COOH) was hkewise fomid to have a 



" K. Bernhard, Z. physiol. Chem., 269, 135-145 (1941). 



90 K. Bernhard and H. Lincke, Helv. Chim. Acta, 29, 1457-1466 (1946). 



" J. Baer and L. Bkim, Beilr. chem. Physiol. Pathol, 11, 101-108 (1908). 



