title: An improved synthesis of 24-13C-labeled bile acids using formyl esters and a modified lead tetraacetate procedure.
abstract: An improved synthesis of 24-13C-labeled bile acids has been achieved using formyl derivatives of bile acids and a modified lead tetraacetate procedure. The formylated bile acides were degraded by lead tetraacetate and lithium chloride to formylated 23-chloronorcholanes in 72-83% yield. Formylated 23-chloronorcholanes were converted to nitriles in dimethylformamide, which were then hydrolyzed to obtain C-24 labeled bile acids in yield of 80-90% of labeled sodium cyanide used. This method results in a higher yield and a purer product with less manipulation than previously reported procedures for synthesis of labeled bile acids.
mesh_terms: D001647:Bile Acids and Salts / Q000138:chemical synthesis*; D002247:Carbon Isotopes; D055598:Chemical Phenomena; D002621:Chemistry; D005563:Formic Acid Esters; D007202:Indicators and Reagents; D007553:Isotope Labeling / Q000379:methods; D014316:Tritium
chemical_list: D001647:Bile Acids and Salts; D002247:Carbon Isotopes; D005563:Formic Acid Esters; D007202:Indicators and Reagents; D014316:Tritium