Preparation of radiolabelled 3α-hydroxy-7-keto-5β-cholanic acid and its glycine and taurine conjugates

✍ Scribed by Gerald L. Carlson; Hans Fromm

• Publisher: John Wiley and Sons
• Year: 1979
• Tongue: French
• Weight: 524 KB
• Volume: 16
• Category: Article
• ISSN: 0022-2135
• DOI: 10.1002/jlcr.2580160308

✦ Synopsis

Abstract

3α‐Hydroxy‐7‐keto‐5β‐cholanic acid has been prepared from cholic acid by a route which allowed introduction of ^3^H into positions 11 and 12 of the steroid C ring. Labelling with ^14^C was done by halodecarboxylation and resynthesis of the carboxyl function with ^14^C cyanide. The conjugates of both ^3^H‐ and ^14^C‐labelled compounds with glycine and taurine were prepared. ^14^C‐labelled compounds were prepared by degradation of the carboxyl‐containing side chain to the norchloride, which was used to prepare the homologous ^14^C‐containing nitrile. Hydrolysis afforded the acid in good yield. ^3^H was introduced into the C ring of the steroid nucleus by dehydration of 3α,12α‐dihydroxy‐7‐keto‐5β‐cholanic acid to the Δ^11^‐alkene which was catalytically tritiated. Physical and spectral data are presented to characterize the new compounds and TLC methods for purification are reported.