9 8 



SCIENCE PROGRESS 



it is possible to arrive at the body dibromcholestandione by 

 three different paths : 



CH 2 CH 2 



CH, CH, 



CH CH CH 2 



I I I 



CH CH 2 CH 



CHOH CH 2 

 Cholesterine 

 m.p. 147 

 (C 17 H3o) ■ CioHitjO 



by Cr0 3 v 



CH 2 CH 2 

 CH CH CH, 

 CH CH CO 



COO.C.H 

 Hypothetical body 



(C17H30) . Ci Hi 2 O 3 



CH CH CH 2 



I I I 



CH CH C.N0 2 



CHOHCH 

 Oxynitrocholesterine 

 m.p. 123 

 (C 17 H 28 0).C.oH l3 O.N0 2 



>V 



by CrOa 



CH 2 CH 2 



CH CH CH 2 



I I I > 



CH CH CO -H,0 



CO CHOH 

 Oxycholestendiol 



m.p. 231 

 (Ci 7 H 30 ). Ci Hi 2 O 3 



CH 2 CH 2 



/\/\ 

 CH CH CH 2 



I I I 



CH C CO 



CHOHCH 

 a-Oxycholestenol 



m.p. 180° 

 (C17H30). Ci H 12 O 2 



c<*V 



CH 2 CH 2 



CH CH CH 2 



I I I 



CH CH CO 



CHOHCH, 

 Cholestanonol 

 m.p. 142* 

 (C^H^) . Ci Hi 4 O 2 



vby Cr0 2 



CH 2 CHo 



CH CH CH 2 



I I I 



CH CH CO 



CO CH 2 



Cholestandione 



m.p. 169 

 (C^Hsq) . Ci Hi 2 O 2 



\' 



CH, CH. 



CH CH CH 2 



I I I 



CH CH CO 



\/%/ 

 CO CH 



Oxycholestenone 

 m.p. 122 



(Q7H30) . Ci H 10 O 2 



+ Br 2 



+ 2 Br, 



CH 2 CH 2 



CH CH CH 2 



I I I 



CH C.Br CO 



CO CH.Br 

 Dibromcholestandione 



m.p. 167° 

 (C 17 Hj ) . Ci Hi O 2 Br 2 



The oxidation of cholesterine with chromic acid gives rise to 

 three neutral products — a-oxycholestenol, oxycholestenone, and 

 oxycholestendiol. Of these the first, C^H^Oa, is a substance 

 apparently unsaturated and containing a CHOH group which 

 is very easily oxidised to carbonyl, giving oxycholestenone, 

 C 2 7H 40 O2. This ketone is certainly unsaturated, yielding with 

 bromine a crystalline dibromide, but the function of the second 

 oxygen atom in both these bodies was for long entirely unknown. 



