| 摘要 |
<p>NEW MATERIAL:A 25-hydroperoxy-24-oxocholestane derivative of formula I (R<1> is H or OH-protecting group; R<2> is H, OH, etc.; R<3> is H; R<4> is H, OH, etc.; R<3> and R<4> may form C-C bond; R<5> and R<6> are H or may form C-C bond). EXAMPLE:25-Hydroperoxy-24-oxocholesterol. USE:An intermediate for the preparation of active vitamin D3. PROCESS:A 24-oxocholestane derivative is oxidized with oxygen in a solvent, e.g. benzene, dioxane or propanol, in the presence of a basic compound, e.g. sodium or potassium tert-butoxide, at -40-20 deg.C, preferably -20-0 deg.C, to give the compound of formula I.</p> |
