Addition of Azoimide to Unsaturated Ketones in the Steroid Series. Synthesis of N-(17β-Hydroxy-3-oxo-5α-androstan-15β-yl)succinamoic Acid and Its Evaluation as Hapten for Dihydrotestosterone Immunoanalysis

Abstract

Addition of azoimide to 17-oxoandrosta-5,15-dien-3β-yl acetate or 17-oxo-5α-androst-15-en-3β-yl acetate gave in both cases corresponding 15β-azido derivatives. 15β-Azido-17-oxo-5α-androstan-3β-yl acetate was selectively reduced to 17β-hydroxy derivative and protected as methoxymethyl ether. Subsequent reduction of azide group and condensation with methyl hydrogen succinate gave a protected succinylamino derivative. Deacetylation and oxidation then led to dihydrotestosterone (DHT) series. Successive removal of protecting groups gave N-(17β-hydroxy-3-oxo-5α-androstan-15β-yl)succinamoic acid, an experimental hapten for DHT. Its conjugate with bovine serum albumin was used for immunization of rabbits and corresponding antisera were evaluated in RIA using [3H]-DHT as a tracer. The results are comparable with standard kits based on antisera generated using DHT derivatives with connecting bridge in position 7.