27240-83-1Relevant articles and documents
Synthesis of deuterium-labeled 17-hydroxyprogesterone suitable as an internal standard for isotope dilution mass spectrometry
Shimizu,Yamaga,Kohara
, p. 283 - 297 (1988)
A synthesis is reported of 17-hydroxyprogesterone, labeled with four atoms of deuterium at ring C and suitable for use as an internal standard for isotope dilution mass spectrometry. Base-catalyzed equilibration of methyl 3α-acetoxy-12-oxo-cholanate (III) with 2H2O, followed by reduction of the 12-oxo group by the modified Wolff-Kisher method using [2H]diethylene glycol and [2H]hydrazine hydrate afforded [11, 11, 12, 12, 23, 23-2H]lithocholic acid (V). The Meystre-Miescher degradation of the side chain of V yielded 3α-hydroxy-5β-[11, 11, 12, 12-2H]pregnan-20-one (X). Oxidation of the 3,20-enol-diacetate of X with perbenzoic acid followed by saponification afforded 3α,17-dihydroxy-5β-[11, 11, 12, 12-2H]pregnan-20-one (XI). Oxidation of XI with N-bromoacetamide yielded 17-hydroxy-5β-[11, 11, 12, 12-2H]pregnane-3,20-dione (XII). Bromination of XII followed by dehydrobromination yielded 17-hydroxy-[11, 11, 12, 12-2H] progesterone (XIV) consisting of 0.3% 2H0-, 1.1% 2H1-, 8.6% 2H2-, 37.1% 2H3-, 52.1% 2H4-, and 0.8% 2H5-species.
Bile acid-derived molecular tweezers: Study of solvent effects in binding, and determination of thermodynamic parameters by an extraction-based protocol
Potluri,Maitra
, p. 7764 - 7769 (2000)
A family of bile acid-based molecular tweezers (1-3) were synthesized, and their binding affinities with picric acid in different solvents were evaluated using a simple extraction-based protocol. The binding affinities increased in nonpolar solvents. The size of the solvent molecule did not affect the binding constant. Thermodynamic parameters for the binding of picric acid in CCl4 were also determined by this method. Binding constants of these tweezers with trinitrofluorenone in CDCl3 were determined by NMR titration.
Chemical Synthesis of Rare Natural Bile Acids: 11α-Hydroxy Derivatives of Lithocholic and Chenodeoxycholic Acids
Namegawa, Kazunari,Iida, Kyoko,Omura, Kaoru,Ogawa, Shoujiro,Hofmann, Alan F.,Iida, Takashi
, p. 403 - 411 (2018/06/08)
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 B2H6/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 NaClO2 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.
Chemical synthesis of uncommon natural bile acids: The 9α-hydroxy derivatives of chenodeoxycholic and lithocholic acids
Iida, Takashi,Namegawa, Kazunari,Nakane, Naoya,Iida, Kyoko,Hofmann, Alan Frederick,Omura, Kaoru
, p. 1397 - 1402 (2016/10/03)
The chemical synthesis of the 9α-hydroxy derivatives of chenodeoxycholic and lithocholic acids is reported. For initiating the synthesis of the 9α-hydroxy derivative of chenodeoxycholic acid, cholic acid was used; for the synthesis of the 9α-hydroxy derivative of lithocholic acid, deoxycholic acid was used. The principal reactions involved were (1) decarbonylation of conjugated 12-oxo-Δ9(11)-derivatives using in situ generated monochloroalane (AlH2Cl) prepared from LiAlH4 and AlCl3, (2) epoxidation of the deoxygenated Δ9(11)-enes using m-chloroperbenzoic acid catalyzed by 4,4'-thiobis-(6-tert-butyl-3-methylphenol), (3) subsequent Markovnikov 9a-hydroxylation of the Δ9(11)-enes with AlH2Cl, and (4) selective oxidation of the primary hydroxyl group at C-24 in the resulting 3α,9α,24-triol and 3α,7α,9α,24-tetrol to the corresponding C-24 carboxylic acids using sodium chlorite (NaClO2) in the presence of a catalytic amount of 2,2,6,6-tetramethylpiperidine 1-oxyl free radical (TEMPO) and sodium hypochlorite (NaOCl). The 1H- and 13C-NMR spectra are reported. The 3α,7α,9α-trihydroxy-5β-cholan-24-oic acid has been reported to be present in the bile of the Asian bear, and its 7-deoxy derivative is likely to be a bacterial metabolite. These bile acids are now available as authentic reference standards, permitting their identification in vertebrate bile acids.
synthetic bile acid preparation
-
, (2015/09/28)
no abstract published
