versatile oxidation reagent. With this reagent different types of primary and secondary hydroxy compounds are converted to their carbonyl derivatives. Aldehydes could be transformed to their carboxylic acids. Benzylic chloride and bromides are converted to their aldehydes and carboxylic acids. Semicarbazide and 2,4-dinitrophenylhydrazine derivatives of benzylic carbonylcompounds undergo carbon-nitrogen
[EN] METHODS FOR PREPARING BILE ACIDS<br/>[FR] PROCÉDÉS DE PRÉPARATION D'ACIDES BILIAIRES
申请人:MEDYTOX INC
公开号:WO2019024920A1
公开(公告)日:2019-02-07
The present disclosure provides methods of preparing cholic acid, deoxycholic acid, or chenodeoxycholic acid, an ester thereof, or a pharmaceutically or cosmetically acceptable salt thereof, and novel and useful synthetic intermediates, for example, as described for methods 1, 1A, 1B, 2, 3, 3A, and 4. The method can start with a plant derived steroid as a starting material, such as dehydroepiandrosterone (DHEA) or Acetyl-dehydroepiandrosterone (Ac-DHEA). Also provided are pharmaceutical or cosmetic compositions and uses thereof, which comprise one or more of cholic acid, deoxycholic acid, or chenodeoxycholic acid, an ester thereof, or a pharmaceutically or cosmetically acceptable salt thereof, which is of high purity, for example, free of animal derived impurities.
Efficient Chemoselective Mild Deprotection of S,Sand S,O-Acetals and Ketals with Electrophilic Halogens
作者:Hamid Reza Shaterian、Hassan Hadadzadeh
DOI:10.1080/10426500500326305
日期:2006.6
A novel and simple method for the chemoselective deprotection of S,S- and S,O-acetals and ketals in the presence of their O,O-analogs with electrophilic halogens to their corresponding carbonyl compounds is described using N-bromosuccinimide, N-chlorosuccinimide, 2,4,4,6-tetrabromo-2,5-cyclohexen-1-one, trichlorocyanuric acid, or molecular bromine in aqueous acetonitrile. The use of these reagents in