Oestrogen conjugates of human late-pregnancy urine

Abstract

The separation of the estrogen conjugates in late-pregnancy urine into 2 groups, peaks I and II; by gel filtration on Sephadex G-25 (Beling, 1963) has been shown to be affected by the presence of urate, which delays the elution of peak II conjugates. By reapplication to a Sephadex column, peak I conjugates have been further separated into 2 groups (peaks IA and IB) and the metabolites in urine effecting this separation have been studied. Further analysis of the mixed conjugates in the main groups IA, IB and II by ion-exchange and partition chromatography had led to the identification of some of the conjugates present. Estriol 3-sulphate 16a-glucuronide and 16[alpha]-hydroxyestrone 3-sulphate 16[alpha]-glucuronide have been identified in peak IA. The main components of peaks IB have been identified as estrone 3-glucuronide and estriol 3-glucuronide. The major conjugate in peak II was estriol 16a-glu-curonide and no estriol 17[beta]-glucuronide was found; small amounts of the ring-D monoglucuronides estradiol 17[beta]-glucuronide, 16-epiestriol 16[beta]-glucuronide and 16[alpha]-hydroxyestrone 16[alpha]-glucuronide were found in this fraction. The behavior of synthetic estrogen monoglucuronides has been used as a guide in separation.