Steroid intermediates and process for their preparation.
摘要
<p>The invention comprises steroid intermediates of the general formula I <IMAGE> The steroid intermediates obtainable according to the invention are suitable for synthesising 13-ethyl-11-methylene-18,19-bisnor-17 alpha -pregn-4-en-20-yn-17-ol (desogestrel). Processes for the preparation of the steroid intermediates of the general formula I are also described. The olefination of the 11-oxosteroids is carried out with exposure to ultrasound.</p>
