Occurrence of both (25R)- and (25S)-3 alpha,7 alpha,12 alpha-trihydroxy-5 beta-cholestanoic acids in urine from an infant with Zellweger's syndrome.

Urine from a patient with Zellweger's syndrome was examined for bile acids after fractionation into three groups according to mode of conjugation. 3 alpha,7 alpha,12 alpha-Trihydroxy-5 beta-cholestanoic acid was the predominant bile acid of the unconjugated and glycine-conjugated bile acid fractions. Smaller amounts of cholic acid and 1 beta-, 6 alpha-, 24-, and 26-hydroxylated derivatives of 3 alpha,7 alpha,12 alpha-trihydroxy-5 beta-cholestanoic acid were found in both fractions in similar proportions. The bile acid spectrum of the taurine-conjugated bile acid fraction was different from those of the other two fractions in the occurrence of two new compounds as the major constituents. These compounds were tentatively identified as two epimers at C-23 of 3 alpha,7 alpha,12 alpha-trihydroxy-5 beta-cholestano-26,23-lactone, which were probably artifacts formed from the corresponding tetrahydroxycholestanoic acids during the procedures for extraction after hydrolysis. High-performance liquid chromatographic analysis revealed that 3 alpha,7 alpha,12 alpha-trihydroxy-5 beta-cholestanoic acid excreted into the urine as the unconjugated form consisted of a mixture of (25R)- and (25S)-isomers in the ratio of about 7:3.