NEW PREPARATION PROCESS FOR A16ß-METHYL STEROID AND NEW INTERMEDIATES

摘要

The invention relates to the preparation of an intermediate of betamethasone of formula (I): from the cyanhydrin of formula (II) in which rings A and B represent: where K is an oxo radical or a protector group of the oxo radical and R1 an ether or ester remainder, as well as new intermediates.