754 URINE. 



The salts with the alkalies, barium, calcium, and silver are soluble in 

 water, and of these salts that with barium and, to a still higher degree, 

 the silver salt are soluble with difficulty in alcohol. The free acid and 

 its salts are precipitated by mercuric nitrate and acetate, and by this 

 last reagent even from solutions strongly acidified with acetic acid. Basic 

 lead acetate does not precipitate the pure acid. 



Oxyproteic acid is the name given by BONDZYNSKI and GOTTLIEB l 

 to a nitrogenous acid containing sulphur, and which they prepared from 

 human urine, which has recently been further studied by BONDZYNSKI, 

 DOMBBOWSKI and PANEK. This acid contained C 39.62, H 5.64, N 

 18.08, S 1.12, and 35.54 per cent, and also contains sulphur which could 

 be split off. On cleavage it yields no tyrosine, nor does it give EHRLICH'S 

 diaao reaction, the xanthoproteic nor the biuret reaction. It gives a 

 faint indication of a MILLON reaction and is not precipitated by phos- 

 photungstic acid, hence it leads to an error in the PFLUGER-BOHLAND 

 method for estimating urea. The acid soluble in water is precipitated 

 by mercuric nitrate and acetate in neutral solutions, but is not precipitated 

 by basic lead acetate. The salts of this acid are readily soluble in water 

 and more soluble in alcohol than the corresponding salts of antoxy- 

 proteic acid. 



The acid which is found in large quantities, especially in the urine of 

 dogs poisoned with phosphorus (BONDZYNSKI and GOTTLIEB), is considered 

 like the preceding acid as an intermediary oxidation product of the pro- 

 teins, and oxyproteic acid seems to represent a higher state of oxidation 

 or a demolition of the proteins than the antoxyproteic acid. 



The acid called uroproteic acid by CLOETTA is probably a mixture of several 

 bodies, according to the recent investigations of BONDZYNSKI; DOMBROWSKI, and 

 PANEK. The same applies also to the barium oxyproteate prepared by PREGL 2 

 from the urine. 



Alloxyproteic acid is a third acid related to the above, which was 

 first isolated by BONDZYNSKI and PANEK 3 from the urine and then care- 

 fully studied with DOMBROWSKI. The composition is: C 41.33, H 

 5.70, N 13.55, S 2.19, and 37.23 per cent, based upon new investigations. 

 The free acid is soluble in water. It gives neither the biuret reaction 

 nor EHRLICH'S reaction, and is not precipitated by phosphotungstic 

 acid. Differing from the other acids, it is precipitated by basic lead 

 acetate, and its salts are only slightly soluble in alcohol. According to 



iCentralbl. f. d. med. Wissensch., 1897, No. 33. 



2 Cloetta, Arch, f . exp. Path. u. Pharm., 40; Pregl, Pfliiger's Arch., 75. 



8 Ber. d. d. chem. Gesellsch., 35. 



