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Updated: Aug 18, 2026

Separation of Aldehydes and Reactive Ketones from Mixtures Using a Bisulfite Extraction Protocol
Published on: April 2, 2018
Use of borohydride reduction in the separation of estrogen carbonyls
Abstract:
The chromatographic behavior of the estrogen carbonyls, equilenin, equilin, and estrone, and their respective sodium borohydride reduction products has been studied. The separation of the 17 alpha-hydroxy reduced compounds is superior to the separations achieved for the parent carbonyls using both reversed-phase and normal-phase systems. The reductions appear quantitative by the chromatographic systems used but other work indicates that a small quantity of 17 alpha-hydroxy isomer is produced. The separations developed here have been used in the identification of 9-dehydroestrone, an impurity in estrone, and in the identification of the estrogens in a commercial aqueous suspension of estrogenic substances.
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