DIGESTION, ETC. OV STEROLS IN THE 0.1. TRACT 



273 



Ooprostanone Coprostanol(eoprosterol) 



Some of the Biologic Transformations of Cholesterol Taking Place in the Intestine 



The second method by which cholesterol yields coprostanol involves 

 a preliminary conversion to cholestenone. The unsaturated bond of this 

 ketone is reduced with palladium and hydrogen to yield coprostanone; 

 the latter ketone is reduced to coprostanol with platinum and hydro- 

 gen. 148-150 This represents the biological method, as is indicated by the 

 transformation of the intermediate products in vivo to coprostanol. In 

 the first place, Avhen cholestenone was administered to a dog on a meat diet, 



148 H. Grasshof, Z. physiol. Chem., 22S, 249-251 (1934). 



149 H. Grasshof, Z. physiol. Chem., 225, 197-198 (1934). 



150 L. Ruzicka, A. Briingger, E. Eiohenberger, and J. Meyer, Helv. Chitn. Acta, 17, 

 1407-1416 (1934). 



