Steroids. 73. Joint Addition Reactions to 14,15‐Unsaturated Androstanes. Influence of the Positive Charged Halogen on the Regioselectivity The joint addition of positive charged halogens and nitrogenous nucleophils to 14,15‐unsaturated olefins is investigated. It was established that the regioselectivity of the addition reaction is different for bromine and iodine. This surprising result is discussed. Ring closure reactions of the addition products to the corresponding aziridines are investigated.

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Es wird die Einführung von Heterosubstituenten in die 10β‐Stellung von 19‐Norsteroiden durch Öffnung von 5α,10α‐Epoxiden mit nucleophilen Sauerstoff‐, Stickstoff‐, Schwefel‐ und Halogenverbindungen beschrieben.

Steroides. LXX. Stereoselective Epoxidation of 14,15‐Unsaturated Estratriene‐3‐methyl Ethers. On the syn‐Directive Effect of Urethanes The stereochemistry of the epoxidation of 14,15‐unsaturated estratriene‐3‐methyl ethers with peroxyacids is examined. The influence of different 17‐substituents and of the solvent on the stereoselectivity is discussed. Whereas on epoxidation of 17β‐esters and 17β‐ethers mainly 14α, 15α‐epoxides are formed (up to 89%), the 17β‐urethane derivatives yield the 14β, 15β‐epoxides up to 87% by a syn‐directive effect.

The biologically interesting title compound (IV) is synthesized starting from the steroid (Ia) which is transformed to (Ib) by reaction with phenylisocyanate.