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Solid-phase Synthesis of [4.4] Spirocyclic Oximes
Published on: February 6, 2019
Synthesis of ring B unsaturated estriols. Confirming the structure of a diagnostic analyte for Smith-Lemli-Opitz
L W Guo1, C H Shackleton, W K Wilson
1Department of Biochemistry and Cell Biology, Rice University, Houston, Texas 77005, USA.
Abstract:
[structure: see text] Brief partial syntheses are described for ring B unsaturated estriols, which are candidate metabolites diagnostic for Smith-Lemli-Opitz syndrome prenatally. These steroids are also likely metabolites of the Premarin preparation used in estrogen replacement therapy. Equilin (8) was converted in three steps to 7-dehydroestriol, which was isomerized to 8-dehydroestriol. The simplicity of the transformations belies the lability of these previously inaccessible metabolites and their synthetic precursors.
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