Synthesis 2003(4): 0535-0538
DOI: 10.1055/s-2003-37656
PAPER
© Georg Thieme Verlag Stuttgart · New York

The First Syntheses of Multiply Hydroxylated 16,17-Ene-Sterols Possessing the Androst-16-ene-3β,5α-diol Motif

Charles M. Marson*a, Alphonso S. Riojaa, Kelvin E. Smithb, John M. Behanc
a Christopher Ingold Laboratories, Department of Chemistry, University College London, 20 Gordon Street, London WC1H 0AJ, UK
Fax: 44(020)76797463; e-Mail: c.m.marson@ucl.ac.uk;
b Department of Biological Sciences, Queen Mary College, Mile End Road, London E1 4NS, UK
c Quest International, Ashford, Kent TN24 0LT, UK
Further Information

Publication History

Received 19 December 2002
Publication Date:
07 March 2003 (online)

Abstract

5α-Androst-16-ene-3β,5α-diol (12) and 5α-androst-16-ene-3β,5α,6β-triol (16) have been synthesised from dehydroepiandrosterone. Ketalisation and O-silylation of dehydroepiandrosterone enabled the 5α,6α-epoxide 7 to be obtained; reductive cleavage with LiAlH4 and deprotection afforded 3β,5α-dihydroxy-5α-androstan-17-one (9) whose hydrazone was converted into the 15,16-dehydro-16-iodo sterol 11 prior to hydrodeiodination with sodium in ethanol to give 5α-androst-16-ene-3β,5α-diol (12). Reaction of dehydroepiandrosterone with N-bromosuccinimide gave the 3β,5α,6β-ketotriol 13 which by the above three-step sequence of hydrazone formation, conversion into the vinylic iodide and reduction afforded 5α-androst-16-ene-3β,5α,6β-triol 16.