434-16-2Relevant articles and documents
Oxidation of cholesterol by a biomimetic oxidant, cetyltrimethylammonium dichromate
Patel, Sabita,Mishra
, p. 3522 - 3526 (2006)
The oxidation of cholesterol by cetyltrimethylammonium dichromate (CTADC) in dichloromethane (DCM) yielded 7-dehydrocholesterol, while with addition of acetic acid in DCM the product was found to be 5-cholesten-3-one. The kinetics of oxidation of cholesterol by CTADC in DCM, in the presence of acid, was investigated with change in [acid], [cholesterol], [CTADC], [surfactant], temperature, and solvents. The reaction was found to be first order with acetic acid and fractional order with CTADC and cholesterol. Michaelis-Menten-type kinetics was observed with respect to cholesterol. The solvent isotope effect was found to be k(D2O)/k(H2O) = 0.72. The observed experimental data suggest that the reaction occurs in reversed micellar system, akin to an enzymatic environment, and the reaction path involves the intermediate formation of an ester complex, which undergoes decomposition to give the product.
Novel industrial method for preparing vitamin D3 by taking stigmasterol as raw material
-
Paragraph 0010; 0052; 0053, (2021/05/05)
The invention provides a novel industrial method for preparing vitamin D3 by taking stigmasterol as a raw material. The method comprises the following steps: sequentially carrying out hydroxyl acetylation, side chain oxidation, side chain isopentane reduction and hydrogenation on stigmasterol to obtain cholesterol acetate, and then sequentially carrying out oxidation, hydrazone formation, hydrazone removal, hydrolysis, illumination and the like to obtain the vitamin D3. The invention provides a novel method for preparing vitamin D3 from stigmasterol, and the method has the advantages of mild reaction conditions and high yield, and is suitable for industrial production.
ORGANIC SOLVENT NANOFILTRATION OF 7-DEHYDROCHOLESTEROL OR 25-HYDROXY-7-DEHYDROCHOLESTEROL OR THEIR OH PROTECTED FORMS
-
Page/Page column 20, (2021/10/30)
The present invention relates to the purification of 7-dehydrocholesterol or 25-hydroxy-7-dehydrocholesterol or their OH-protected forms, respectively. It has been found that the process using organic solvent nanofiltration allows an efficient reduction of the amount of a new higher molecular compound which is formed in a 5 new synthesis process of of 7-dehydrocholesterol or 25-hydroxy-7-dehydrocholes- terol or their OH-protected forms in small amounts. Said new higher molecular compound can be used as colorant.