26-Deoxy-5/ -ranol

Deoxy-5 -ranol (24S)-27-Nor-5a-cholestane-3a,7a,12a,24-tetrol Some frogs... 

Dehydro-26-deoxy-5a-ranol 3 ,7 ,12a-Trihydroxy-27-nor-5a-cholestan-24-one Bullfrog... 

Noma et al. found 2 keto bile alcohols in unconjugated form in bullfrog bile [42]. Their structures were determined as 24-dehydro-26-deoxy-5a-ranol and its 5 isomer by comparison with synthetic 3a,7a,12a-trihydroxy-27-nor-5a- and 5/8-choles-tan-24-ones, prepared from allocholic acid and chohc acid, respectively [41]. 

Nor-26-deoxy-5a- and 5j8-ranols, 26,27-dinor-5a- and 5j8-cholestane-3a,7a,12a,24-tetrols, were detected by gas-liquid chromatography-mass spectrometry as minor constituents in the bile of a few species of frogs [9]. 

Danielsson and Kazuno have shown that 5j8-ranol is an efficient precursor of cholic acid in bile fistula rats while 26-deoxy-5)S-ranol is not [134]. The mechanism of the side-chain degradation of 5 -ranol is not known but probably an oxidation of the 26-hydroxyl group to a carboxyl group followed by a /S-oxidation. 

Major bile salts in the bullfrog, Rana catesbiana, are 27-nor-5/ -cho-lestane-3a,7a,12a,24,26-pentol (5/5-ranol) and 3a,7a,12a-trihydroxy-5) -cho-lestanoic acid. Betsuki (181,182) has shown that 5j5-cholestane-3a,7a,12a-triol and 3a,7a,12a,24-tetrahydroxy-5)5-cholestanoic acid are converted into 5/5-ranol and 26-deoxy-5)5-ranol. The following sequence of reactions in the... 

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