Synthesis of B,B-dinor-B-secosteroids as potential cardenolide analogues

A novel chemical construction of B,B-dinor-B-secosteroids as simplified cardenolide analogs, starting from the Hajos–Parrish diketone was developed. The synthesis of the equivalent of the steroid A ring was carried out through a Diels–Alder reaction between an appropriate hydroindenyl acrylate derivative and Danishefskyʹs diene.