CHONDROITIN-SULPHURIC ACID. 547 



account of the further decomposition of this last body, sulphuric acid 

 and a reducing substance are formed. 



Chondromucoid is a white, amorphous, acid-reacting powder which 

 is insoluble in water, but dissolves easily on the addition of a little 

 alkali. This solution is precipitated by acetic acid in great excess and 

 by small quantities of mineral acids. The precipitation may be retarded 

 by neutral salts or by chondroitin-sulphuric acid. The solution con- 

 taining NaCl and acidified with HC1 is not precipitated by potassium 

 ferrocyanide. Precipitants for chondromucoid are alum, ferric chloride, 

 sugar of lead, or basic lead acetate. Chondromucoid is not precipitated 

 by tannic acid, and it may by its presence prevent - the precipitation 

 of gelatin by this acid. It gives the usual color reactions for proteins, 

 namely, with nitric acid, with copper sulphate and alkali, with MIL- 

 LON'S and ADAMKIEWICZ-HOPKINS' reagents. 



Chondroitin-sulphuric Acid, CHONDROITIC ACID. This acid, which 

 was first prepared pure, from cartilage, by C. MORNER and identified 

 by him as an ethereal sulphuric acid, occurs, according to MORNER, in 

 all varieties of cartilage and also in the tunica intima of the aorta and 

 as traces in the bone substance. K. MORNER * has also found it in the 

 ox-kidney and in human urine as a regular constituent. Its occurrence 

 in amyloid, as mentioned on page 173, has been disputed by HANSSEN. 

 In the opinion of LEVENE, 2 the glucothionic acid which is prepared from 

 tendon mucoid, and which gives the orcin reaction for glucuronic acid, 

 and yields furfurol on distillation with hydrochloric acid, is not identical 

 with the chondroitin-sulphuric acid, but is probably related thereto. 



Chondroitin-sulphuric acid has the formula CisH^yNSOir, accord- 

 ing to ScHMiEDEBERG. 3 As primary products this acid yields, on 

 cleavage, sulphuric acid and a nitrogenous substance, chondroitin, accord- 

 ing to the following equation: 



Chondroitin, which is similar to gum arabic, and which is a monobasic 

 acid, yields acetic acid and a new nitrogenous substance, chondrosin, 

 as cleavage products, on decomposition with dilute mineral acids: 



Chondrosin, which is also a gummy substance soluble in water, is a 

 monobasic acid and reduces copper oxide in alkaline solutions even 



1 C. Morner, 1. c., and Zeitschr. f. physiol. Chem., 20 and 23; K. Morner, Skand. 

 Arch. f. Physiol., 6. 



2 Zeitschr. f . physiol. Chem., 39. 



3 Arch. f. exp. Path. u. Pharm., 28. 



