In:
Lipids, Wiley, Vol. 53, No. 4 ( 2018-04), p. 403-411
Abstract:
A method for the preparation of 11α‐hydroxy derivatives of lithocholic and chenodeoxycholic acids, recently discovered to be natural bile acids, is described. The principal reactions involved were (1) elimination of the 12α‐mesyloxy group of the methyl esters of 3α‐acetate‐12α‐mesylate and 3α,7α‐diacetate‐12α‐mesylate derivatives of deoxycholic acid and cholic acid with potassium acetate/hexamethylphosphoramide; (2) simultaneous reduction/hydrolysis of the resulting △ 11 ‐3α‐acetoxy and △ 11 ‐3α,7α‐diacetoxy methyl esters with lithium aluminum hydride; (3) stereoselective 11α‐hydroxylation of the △ 11 ‐3α,24‐diol and △ 11 ‐3α,7α,24‐triol intermediates with B 2 H 6 /tetrahydrofuran (THF); and (4) selective oxidation at C‐24 of the resulting 3α,11α,24‐triol and 3α,7α,11α,24‐tetrol to the corresponding C‐24 carboxylic acids with NaClO 2 catalyzed by 2,2,6,6‐tetramethylpiperidine 1‐oxyl free radical (TEMPO) and NaClO. In summary, 3α,11α‐dihydroxy‐5β‐cholan‐24‐oic acid and 3α,7α,11α‐trihydroxy‐5β‐cholan‐24‐oic acid have been synthesized and their nuclear magnetic resonance (NMR) spectra characterized. These compounds are now available as reference standards to be used in biliary bile acid analysis.
Type of Medium:
Online Resource
ISSN:
0024-4201
,
1558-9307
DOI:
10.1002/lipd.2018.53.issue-4
Language:
English
Publisher:
Wiley
Publication Date:
2018
detail.hit.zdb_id:
2030265-4
SSG:
12
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