Collect. Czech. Chem. Commun. 1999, 64, 2019-2034
https://doi.org/10.1135/cccc19992019

Structures and Synthesis of 4a-Homo-7,19-dinorsteroids, X-Ray Crystallography and NMR Spectroscopy

Alexander Kasala,*, Miloš Buděšínskýa, Jan Pelnařa, Michael A. Bruckb,* and Michael F. Brownb

a Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, 166 10 Prague 6, Czech Republic
b Department of Chemistry, University of Arizona, Tucson, Arizona 85721, U.S.A.

Abstract

X-Ray diffraction revealed the absolute configuration of 4aβ-methyl-4a-homo-7,19-dinor- 5α,10α-androstane-3,17-dione. Detailed NMR analysis suggested that the 5α configuration existed in the starting material, 3β-acetoxy-4a-methylidene-4a-homo-7,19-dinor- 5α-androst-9-en-17-one, and related compounds. Thus 5-methyl-5β-estr-9-ene derivatives with a leaving group in position 6β were found to react with nucleophiles to form rearranged 4a-homo-7,19-dinorandrostane derivatives with a 5α configuration.

Keywords: Steroids; Antiandrogens; Solvolysis; Rearrangements; NMR spectroscopy, 1H, 13C; X-Ray diffraction; Absolute configuration; Conformation analysis.