
%0 Journal Article
%A McKinney, Andrew R. 
%A Ridley, Damon D. 
%A Turner, Peter 
%T Equine Metabolites of Norethandrolone: Synthesis of a Series of 19-Nor-17&#945;-pregnanediols and 19-Nor-17&#945;-pregnanetriols
%J Australian Journal of Chemistry
%D 2003/07/18
%V 56
%N 8
%P 829-838
%K 
%R https://doi.org/10.1071/CH03018
%U https://www.publish.csiro.au/paper/CH03018 
%X A range of 19-nor-17&#945;-pregnanediols and 19-nor-17&#945;-pregnanetriols have been synthesized and used to confirm the structures of major equine urinary metabolites of the synthetic anabolic steroid norethandrolone (1). 19-Nor-5&#945;,17&#945;-pregnane-3&#945;,17&#946;-diol (2), 19-nor-5&#945;,17&#945;-pregnane-3&#946;,17&#946;-diol (4), 19-nor-5&#946;,17&#945;-pregnane-3&#945;,17&#946;-diol (6), and 19-nor-5&#946;,17&#945;-pregnane-3&#946;,17&#946;-diol (7) were prepared by stereoselective reduction of the 3-ene-4-one of norethandrolone. The 19-nor-5&#945;,17&#945;-pregnane-3&#946;,16&#945;,17&#946;-triol (8) and 19-nor-5&#945;,17&#945;-pregnane-3&#946;,16&#946;,17&#946;-triol (9) were prepared from 19-nortestosterone (11) by multistep processes in which the critical step involved Grignard additions to 16-acetoxy-17-ones. The triols (20R)-19-nor-5&#945;,17&#945;-pregnane-3&#946;,17&#946;,20-triol (22) and (20S)-19-nor-5&#945;,17&#945;-pregnane-3&#946;,17&#946;,20-triol (23) were prepared from norethindrone (24) by initial selective A-ring reduction, then subsequent modification of the 17-ethynyl group. By comparison of these compounds with post-administration equine urine samples it was possible to establish A-ring reduction with 3&#946;,5&#945; stereochemistry as well as non-stereospecific 16-hydroxylation and 20-hydroxylation as significant metabolic pathways affecting norethandrolone in the horse. 
