Heterocyclic compounds. VII. Synthesis of thiadiazasteroid analogs

The synthesis of a number of β‐northiadiaza steroid analogs has been described. Suitable o‐aminonitriles were acylated with γ‐chlorobutyryl chloride. These amidonitriles were cyclized to substituted γ‐lactams and subsequently to the tetracyclic products. To functionalize the “17‐position” in these steroids, the intermediate γ‐lactams were converted to arylidene derivatives before cyclization to the tetracyclic derivatives.