title: An improved method for the capillary gas chromatographic derivatization of polyhydroxylated steroids having tert-hydroxyl groups.
abstract: An improved method for a suitable derivatization of polyhydroxylated steroids having one or two tert-hydroxyl groups at the 5beta-, 14alpha-, 17alpha-, 24-, and/or 25-positions by capillary gas chromatography (CGC) is described. By using trimethylsilyl triflate as a silylating reagent and 2,6-lutidine as a catalyst, each of 5beta-cholane and 5alpha-cholestane series of steroids was successfully transformed into trimethylsilyl (TMS) ether derivatives to give a single CGC peak under mild conditions. More bulky triethylsilyl (TES) etherification of 14alpha- and 17alpha-hydroxy compounds provided multiple CGC peaks arising from completely- and/or incompletely-derivatized TES ethers accompanied by their thermal elimination products.
mesh_terms: D005410:Flame Ionization; D006900:Hydroxylation; D015394:Molecular Structure; D012794:Sialic Acids / Q000737:chemistry; D021241:Spectrometry, Mass, Electrospray Ionization; D013237:Stereoisomerism; D013256:Steroids / Q000737:chemistry*
chemical_list: D012794:Sialic Acids; D013256:Steroids