COMPOUNDS RET.ATED TO THE CEREBROSIDES 505 



normal beef spleen which has two carbohydrate residues. The ratio of 

 fatty acid to spliingosine to sugar in this case was found to be 1 : 1 : 2. Both 

 ghicose and galactose were present in this cerebroside in a ratio of 2:3. 



The cerebroside differs from a ganglioside in being insoluble in water, with 

 which it forms an emulsion. It is phosphorus-free. The dicerebroside 

 dissolves readily in pyridine; at room temperature, it is difficultly soluble 

 in acetic acid, still less soluble in methanol, and insoluble in acetone. It is 

 a white powder which melts at 240°C. The cerebroside is weakly levo-ro- 

 tatory in pyridine {[af^ = —6.81°). The orcin reaction for neuraminic 

 acid is negative. The fatty acids consist of behenic acid (CH3(CH2)2o- 

 C ^OOH) and lignoceric acid (CH3(CH2)22COOH) . The nature of the carbo- 

 hydrates is not known, but it is believed that they exist as dihexosides. 



