title: Separation of 24- and 25-dehydrocholesterols; and the impure state of commercial desmosterol preparations.
abstract: Chromatographic methods for the separation of 24- and 25-dehydrocholesterols are described. The purities of three commercial samples of 24-dehydrocholesterol examined by thin-layer and gas-liquid chromatography were only 42, 79, and 80%, respectively; a commercial sample of radioactive 24-dehydrocholesterol was shown to contain 40% 25-dehydrocholesterol.
authors.affiliation: Insect Physiology Laboratory, Entomology Research Division, Agricultural Research Service, US Department of Agriculture, Beltsville, Maryland 20705, USA.
authors.forename: J A
authors.initials: JA
authors.lastname: Svoboda
authors.forename: M J
authors.initials: MJ
authors.lastname: Thompson
mesh_terms: D002849:Chromatography, Gas; D002855:Chromatography, Thin Layer; D003684:Dehydrocholesterols / Q000737:chemistry / Q000302:isolation & purification*; D003897:Desmosterol / Q000737:chemistry / Q000302:isolation & purification*; D004340:Drug Contamination
chemical_list: D003684:Dehydrocholesterols; D003897:Desmosterol