1553-56-6Relevant articles and documents
Preparation method of lithocholic acid and intermediates thereof
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, (2021/02/20)
The invention discloses a synthesis method of lithocholic acid and an intermediates thereof. According to the preparation method of the lithocholic acid intermediate, a compound I reacts with hydrogento generate a compound II in a mixed solvent by taking palladium on carbon as a catalyst and adding specific alkali; a low-price botanical bulk fermentation product BA is used as a raw material, andlithocholic acid is synthesized through side chain construction, hydrogenation, reduction, hydrolysis and other reactions; and the selectivity of 5beta hydrogen in the hydrogenation reaction is improved, high-toxicity reagents such as hydrazine hydrate are prevented from being used for hydroxyl due to removal of other animal-derived cholic acids, and the method is environmentally friendly, high insafety, simple in route, mild in reaction condition and suitable for industrial mass production.
Vitamin E analogues differentially inhibit human cytochrome P450 3A (CYP3A)-mediated oxidative metabolism of lithocholic acid: Impact of δ-tocotrienol on lithocholic acid cytotoxicity
Wong, Siew Ying,Teo, Josephine Si Min,Chai, Swee Fen,Yeap, Szu Ling,Lau, Aik Jiang
, p. 62 - 74 (2019/05/28)
Lithocholic acid is a cytotoxic bile acid oxidized at the C-3 position by human cytochrome P450 3A (CYP3A) to form 3-ketocholanoic acid, but it is not known whether this metabolite is cytotoxic. Tocotrienols, in their various isomeric forms, are vitamin E analogues. In the present study, the hypothesis to be tested is that tocotrienols inhibit CYP3A-catalyzed lithocholic acid 3-oxidation, thereby influencing lithocholic acid cytotoxicity. Our enzyme catalysis experiments indicated that human recombinant CYP3A5 in addition to CYP3A4, liver microsomes, and intestinal microsomes catalyzed lithocholic acid 3-oxidation to form 3-ketocholanoic acid. Liver microsomes with the CYP3A5*1/*3 and CYP3A5*3/*3 genotypes were associated with decreased lithocholic acid 3-oxidation. α-Tocotrienol, γ-tocotrienol, δ-tocotrienol, and a tocotrienol-rich vitamin E mixture, but not α-tocopherol (a vitamin E analogue), differentially inhibited lithocholic acid 3-oxidation catalyzed by liver and intestinal microsomes and recombinant CYP3A4 and CYP3A5. Compared to lithocholic acid 3-oxidation, CYP3A-catalyzed testosterone 6β-hydroxylation was inhibited to a lesser extent by α-tocotrienol, γ-tocotrienol, δ-tocotrienol, and a tocotrienol-rich vitamin E mixture. δ-Tocotrienol inhibited lithocholic acid 3-oxidation by a mixed mode. Like lithocholic acid, 3-ketocholanoic acid was also cytotoxic in human intestinal and liver cell models. δ-Tocotrienol decreased the extent of lithocholic acid 3-oxidation and this inhibition was associated with enhanced cytotoxicity in LS180 cells treated with δ-tocotrienol and lithocholic acid. Overall, vitamin E analogues inhibited in vitro lithocholic acid 3-oxidation in an isomer-dependent manner, with inhibition occurring with tocotrienols, but not α-tocopherol. The enhanced lithocholic acid toxicity by δ-tocotrienol in a human intestinal cell model warrants future investigations in vivo.
Iron Catalysis for Room-Temperature Aerobic Oxidation of Alcohols to Carboxylic Acids
Jiang, Xingguo,Zhang, Jiasheng,Ma, Shengming
supporting information, p. 8344 - 8347 (2016/07/26)
Oxidation from alcohols to carboxylic acids, a class of essential chemicals in daily life, academic laboratories, and industry, is a fundamental reaction, usually using at least a stoichiometric amount of an expensive and toxic oxidant. Here, an efficient and practical sustainable oxidation technology of alcohols to carboxylic acids using pure O2 or even O2 in air as the oxidant has been developed: utilizing a catalytic amount each of Fe(NO3)3·9H2O/TEMPO/MCl, a series of carboxylic acids were obtained from alcohols (also aldehydes) in high yields at room temperature. A 55 g-scale reaction was demonstrated using air. As a synthetic application, the first total synthesis of a naturally occurring allene, i.e., phlomic acid, was accomplished.
