Studies on Analysis of Bile Acids. Preparation of 3-Glucuronides of 7- and 12-Oxo Bile Acids

Abstract

The 3-glucuronides of unconjugated and glyco- and tauro-conjugated bile acids having a 7- or 12-oxo group have been synthesized. Introduction of a glucuronyl residue at the C-3 position was achieved by the Koenigs-Knorr reaction using cadmium carbonate as a catalyst. The 3-glucuronides of conjugated bile acids were prepared by three sequential reactions : esterification with p-nitrophenol, glucuronidation at C-3, and amide formation with ethyl glycinate or taurine. The nuclear magnetic resonance spectral properties of 3-glucuronides of oxo bile acids and related compounds are briefly discussed.