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After Δ6-lithocholic acid was injected into the cecum of rats, lithocholic acid was identified as a metabolite in feces.When the labeled Δ6-bile acid was injected intraperitoneally into bile-fistula rats, radioactivity excreted in bile was contained most abundantly in the taurine-conjugated fraction of bile acids.In the fraction, taurine conjugate of Δ6-lithocholic acid but of neither lithocholic acid nor other bile acids was found.The results showed that Δ6-lithocholic acid was reduced to lithocholic acid by intestinal flora but not by the liver, which, however, was capable of conjugating Δ6-lithocholic acid with taurine.

In order to confirm the structure of alpha-trichechol, the major bile alcohol of the West Indian manatee, chemical synthesis of 5 beta-cholestane-3 alpha,6 beta,7 alpha,25,26-pentol was carried out. The chain of 3 alpha-hydroxy-5 beta-chol-6-en-24-oic acid was elongated by an Arndt-Eistert reaction to form 3 alpha-hydroxy-26,27-dinor-5 beta-cholest-6-en-25-oic acid. The unsaturated C25 bile acid was converted into 3 alpha,6 beta,7 alpha-trihydroxy-25-homo-5 beta-cholan-25-oic acid by 1,2-glycol formation of the delta 6-double bond. The acetylated derivative of the trihydroxy C25 bile acid was then converted into 3 alpha,6 beta,7 alpha,26-tetraacetoxy-27-nor-5 beta-cholestan-25-one by successive treatment with thionyl chloride, diazomethane, and acetic acid. A Grignard reaction of the 25-oxo compound with methylmagnesium iodide afforded the desired bile alcohol, 5 beta-cholestane-3 alpha,6 beta,7 alpha,25,26-pentol. By direct comparison with the synthetic pentahydroxy bile alcohol, the structure of the naturally occurring alpha-trichechol was determined to be 5 beta-cholestane-3 alpha,6 beta,7 alpha,25,26-pentol.