Cholestanes and Cholanes

The 13C NMR spectrum of 2,6-dimethyloctane can be used for assigning the resonances of the cholestane side chain. Applying the rules proposed by Grant and Paul [85], all signals of the model compound 2,6-dimethyloctane can be identified. The Grant-Paul parameters also helped in identifying the side chain resonances of ergosterol [65 a]. 

Inversion of ring A causes significant shifts of the carbon signals of rings A and B in steroids. In 5/5-cholestane, the C-19 methyl carbon resonates about 12 ppm towards 

5a-Andro- 5a-Andro- 5a-Andro- 5a-Andro- 5a-Andro- 5a-Andro- 5a-Andro- 5a-Andro- 5a-Andro- 

stane stan-1-one stan-2-one stan-3-one stan-4-one stan-6-one stan-7-one stan-11-one stan-12-one 

C- CDC1, CDClj CDC13 CDC13 CDCI3 CDCI3 CDClj CDCI3 CDCl, 

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