| 摘要 |
<p>The invention provides a novel general process for the manufacture of 6.beta.,7-methylene-3-oxo-4-ene-steroids by successlvely a)reacting a 3?,5.beta.-dihydroxy-6-ene-steroid which is optionally etherified or esterified in the 3-position with a zinc/copper-methylene iodide reagent to introduce the 6.beta.,7-methylene bridge, b) liberating sn etherified or esterified 3-hydroxyl group if such a group is present,c) tresting the resultant 6.beta.,7-methylene-3?,5.beta.-dihydroxy-steroid with an oxidising agent to dehydrogenate the 3-hydroxyl group to the oxo group, and d) dehydrating the 6.beta.,7-methylene-5.beta.-hydroxy-3-oxo-steroid to form the 4,5-double bond. The starting materials, which form a novel class of compounds, can be obtained by a novel process by converting a 5.beta.,6oxido-3?-hydrox -steroid with a selenol, for example phenylselenol, to a 6.alpha.-alkyl- or arylseleno-3?,5.beta.-dihydroxy-steroid, oxidising this compound with a peroxidic reagent, for example hydrogen peroxide, in a weakly acid medium to give the corresponding 6-selenonyl compound, and converting this compound, preferably by treatment with a base, preferably with 1,5-diazabicyclo¢4,3,0!non-5-ene, to give the 3?,5.beta.dihytroxy-6-ene-steroid. During the course of these reactions, the 3-hydroxyl group is preferably temporarily protected by esterification or etherification. - la</p> |
