POTENTIAL BILE-ACID METABOLITES .2. 3,7,12-TRISUBSTITUTED 5 BETA-CHOLANIC ACIDS

Possible implication of bile acids in the development of colon cancer has stimulated interest in the identity of unidentified metabolites of the primary acids. This paper reports the preparation of two new 12β-hydroxy stereoisomers of cholic acid and several related derivatives. A mild method of inversion of axially substituted C-3 hydroxy bile acid derivatives was uncovered when the 3β, 7α-dihydroxy keto compound (4), catalytically hydrogenated with Raney nickel, unexpectedly gave rise to a 3α-hydroxyl product. 1HNMR and high pressure LC were of key importance in characterizing the compounds and determining their purity. © 1979, American Chemical Society. All rights reserved.