Lagodeoxycholic acid

Several other atypical acids were eventually isolated from various species. Ursodeoxycholic acid, first isolated in crystalline form from bear bile in 1927 (58), was identified as the 7/S-epimer of chenodeoxycholic acid. The so-called /3-hyodeoxycholic acid (3 3,6a), which Kimura obtained in small amounts from pig bile (59), was structurally identified in the course of a thorough investigation of the four possible 3,6-dihydroxycholanic acids (60). The lagodeoxycholic acids isolated from rabbit bile by Kishi (61) were not characterized until the recent studies of Danielsson et al. (62) identified one of these compounds as allodeoxycholic acid. The contention that one of them may have been the 12 -epimer of deoxycholic acid was placed in doubt by Koechlin and Reichstein (63), who prepared that acid and found that it did not exhibit the physical properties of the natural material. 

The natural occurrence of the 5a-epimer of deoxycholic acid was first demonstrated by Danielsson, Kallner, and Sjovall (62). The original isolation of this compound was probably by Kishi (61) who named the unidentified acid lagodeoxycholic acid from rabbit bile. In addition to its occurrence in rabbit bile, allodeoxycholic acid is present in rabbit feces (62) and accumulates as the glycine conjugate in gallstones of rabbits fed cholestanol (168). Allodeoxycholic acid may be synthesized from cholic acid by reactions similar to the preparation of allocholic acid (62,168). 

Prior to the identification of /3-lagodeoxycholic acid this acid was prepared by Yukawa (35) and by Hofmann and Mosbach (36) from the key intermediate, V, by the Huang-Minlon reduction. Although this reduction is... 

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