Oxidation of cholesterol by a biomimetic oxidant, cetyltrimethylammonium dichromate.
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.
Patel
Sabita
S
Center of Studies in Surface Science and Technology, Department of Chemistry, Sambalpur University, Jyoti Vihar-768019, Orissa, India.
Mishra
B K
BK
D002593:Cetrimonium Compounds / Q000737:chemistry; D002784:Cholesterol / Q000737:chemistry*; D002789:Cholesterol Oxidase / Q000378:metabolism; D002840:Chromates / Q000737:chemistry; D016877:Oxidants / Q000737:chemistry; D010084:Oxidation-Reduction; D013816:Thermodynamics
D002593:Cetrimonium Compounds; D002840:Chromates; D016877:Oxidants; D002784:Cholesterol; D002789:Cholesterol Oxidase; C034944:chromic acid