HYDROLYSIS PRODUCTS OF CEREBROSIDES 



495 



Table 12 



Specific Rotation of Cerebronic Acid Samples as Related to Solvent and 



Purity as Determined from Melting Point 



" p. A. Levene and F. A. Tavlor, J. Biol. Chem., 80, 227-230 (1928). 



» P. A. Levene and W. A. Jacobs, /. Biol. Chem., 12, 381-388 (1912). 



<= O. Rosenheim, Biochcin. J., 10, 142-159 (1916). 



^ E. Klenk, Z. pfujsiol. Chem., 174, 214-232 (1928). 



' Sample obtained bv hydrogenation of hvdro.xynervonic acid. 



^ P. A. Levene and C. J. West, J. Biol. Chem., 26, 115-120 (1916). 



P. A. Levene and V. A. Taylor, /. Biol. Chem., 52, 227-240 (1922). 



from hot alcohol as a voluminous, amorphous mass on the addition of 

 lithium acetate. ''^•■' Magnesium cerebronate is another salt which is 

 insoluble in hot alcohol. ■*-^^ 



b. Lignoceric Acid, (a) Structure. Lignoceric (tetracosanic) acid, CH3- 

 (CHo)2>C00H, is the fatty acid separating on hydrolj-sis of cerasine. Syn- 

 thetic lignoceric acid melts at 85-86°C.^-'"*'*-'^ Brigl and Fuchs*^^ obtained 

 two modifications of lignoceric acid from beech tar, one of which was iden- 

 tical with the synthetic product while the second form, which was probably 

 a pol}Tnorphic modification, melted about 11°C. lower. The first product 

 corresponded in all properties to synthetic lignoceric acid. Further proof 

 that the fatty acid of cerasine is identical with lignoceric acid was brought 

 forward by Levene, Taylor, and Haller,''" who demonstrated that no frac- 

 tionation could be obtained when the methyl esters of lignoceric acid pre- 

 pared from peanut oil and from cerasine were mixed and distilled in vacuo. 



«3 E. Klenk, Z. physwl. Chem., 166, 268-286 (1927). 



«* IL Meyer, L. Brod, and \V. Soyka, Monalsh., 3.',, 111.3-1142 (1913). 



*^= P. Brigl, Z. phijiiiol. Chem., 95, 161-194 (1915). 



«6 P. Brigl and K. Fuchs, Z. physiol. Chem., 119, 280-311 (1922). 



«' P. A. Levene, F. A. Taylor, and II. L. Ilaller, ./. Biol. Chem., 61, 157-161 (1924). 



