Isolation of 17-Epiœstriol from the Urine of Pregnant Women

Abstract

THE isolation of 16α-hydroxyœstrone in 1957 by Marrian, Watson and Panattoni¹ led these authors to suggest that this compound might be the metabolic intermediate in the ‘hydration’ of œstrone to œstriol. In the same year, Brown and Marrian² reported that about 40 per cent of 16α-hydroxyœstrone when administered to human subjects was afterwards excreted in the urine as œstriol. Breuer, Nocke and Knuppen³ found after incubation of 16α-hydroxyœstrone with slices of normal human liver in addition to œstriol a second metabolite which was identified as 17-epiœstriol (œstra-1,3,5-triene-3,16α,17α-triol). In view of these findings it seemed reasonable to assume that 17-epiœstriol might be a normally occurring metabolite of the œstrogens, and therefore, an attempt has been made to isolate 17-epiœstriol from urine during pregnancy.