25-Hydroxy-24-oxocholestane derivatives and preparation thereof

摘要

This invention relates to novel 25-hydroxy-24-oxocholestane derivatives and a process for preparing them. The novel 25-hydroxy-24-oxocholestane derivatives of this invention can easily be converted to 24,25-dihydroxycholecalciferol or 1 alpha ,24,25-trihydroxycholecalciferol which is known as useful for medicine controlling the calcium metabolism of warm-blooded animals. Moreover, 25-hydroxy-24-oxocholestane derivatives can be converted to novel 25-hydroxy-24-oxocholecalciferol expressed by the following formula <IMAGE> and novel 1 alpha ,25-dihydroxy-24-oxocholecalciferol of the formula <IMAGE> which are useful for medicine. The new 25-hydroxy-24-oxocholestane derivatives in the present invention are very useful as the intermediates for the synthesis of a variety of active vitamin D3.