83-49-8Relevant articles and documents
PROCESS FOR THE PREPARATION OF CHOLANIC ACIDS
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Page/Page column 2, (2008/06/13)
A process for the preparation of high purity cholanic acids, typically in purity equal to or higher than 99%.
A process for the preparation of cholanic acids
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Page/Page column 3, (2010/11/30)
A process for the preparation of high purity cholanic acids, typically in purity equal to or higher than 99%.
Xanthomonas maltophilia CBS 897.97 as a source of new 7β- and 7α-hydroxysteroid dehydrogenases and cholylglycine hydrolase: Improved biotransformations of bile acids
Pedrini, Paola,Andreotti, Elisa,Guerrini, Alessandra,Dean, Mariangela,Fantin, Giancarlo,Giovannini, Pier Paolo
, p. 189 - 198 (2007/10/03)
The paper reports the partial purification and characterization of the 7β- and 7α-hydroxysteroid dehydrogenases (HSDH) and cholylglycine hydrolase (CGH), isolated from Xanthomonas maltophilia CBS 897.97. The activity of 7β-HSDH and 7α-HSDH in the reduction of the 7-keto bile acids is determined. The affinity of 7β-HSDH for bile acids is confirmed by the reduction, on analytical scale, to the corresponding 7β-OH derivatives. A crude mixture of 7α- and 7β-HSDH, in soluble or immobilized form, is employed in the synthesis, on preparative scale, of ursocholic and ursodeoxycholic acids starting from the corresponding 7α-derivatives. On the other hand, a partially purified 7β-HSDH in a double enzyme system, where the couple formate/formate dehydrogenase allows the cofactor recycle, affords 6α-fluoro-3α, 7β-dihydroxy-5β-cholan-24-oic acid (6-FUDCA) by reduction of the corresponding 7-keto derivative. This compound is not obtainable by microbiological route. The efficient and mild hydrolysis of glycinates and taurinates of bile acids with CGH is also reported. Very promising results are also obtained with bile acid containing raw materials.
Catalytic oxidations of steroid substrates by artificial cytochrome p-450 enzymes.
Yang, Jerry,Gabriele, Bartolo,Belvedere, Sandro,Huang, Ying,Breslow, Ronald
, p. 5057 - 5067 (2007/10/03)
Catalysts comprising manganese-porphyrins carrying cyclodextrin binding groups are able to perform hydroxylations with substrate selectivity and regio- and stereoselectivity and high catalytic turnovers. The geometries of the catalyst/substrate complexes override intrinsic substrate reactivities, permitting attack on geometrically accessible saturated carbons of steroids in the presence of secondary carbinol groups and carbon-carbon double bonds, as in enzymatic reactions. Selective hydroxylations of steroid carbon 9 positions are of particular practical interest.
