Progesterone cholesterol mixture

Figure 9.85 Normal phase HPLC profiles of the reaction product of the cholesterol side chain cleavage system. Peaks were identified on the basis of their retention times. (i4) Without cholesterol oxidase treatment. Cholesterol (100 nmol) was incubated with cytochrome P450scc (70 pmol) in the presence of adrenodoxin, adrenodoxin reductase, and an NADPH-generating system. Monitoring was at 214 nm. Peaks 1, cholesterol 2, pregnenolone 3, deoxycorticosterone acetate (internal standard) (B) The reaction mixture of (A) was further incubated with cholesterol oxidase at 37°C for 10 minutes. Monitoring was at 240 nm. Peaks 1, cholestenone 2, progesterone 3, deoxycorticosterone acetate (internal standard). (From Sugano et al., 1989.)...

The addition of bromine and chlorine azide to unsaturated steroids is generally diastereoselective, when both the simple and induced diastereoselectivity are considered. In fact, a single enantiomer was obtained from 5a-cholest-2-ene (8)35,36, cholesterol (9)51, and progesterone (10)52 (in this case with undetermined configuration). Testosterone esters, however, afforded mixtures of stereoisomers52. 

Cholesterol has been converted into lOa-cholesterol by a method essentially identical with that used to prepare lOa-progesterone. Dehydration of (293) produced a mixture of A - and A -3-ketones in which the former predominated. Each could be converted to the same A -enol acetate which, on reduction with sodium borohydride, afforded lOa-cholesterol. 

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