Studies of Acetylated Corticosteroids and Related 20-Oxopregnane Derivatives by Gas Liquid Chromatography

Quantitative Separation of Free Estrogens by Liquid Partition Chromatography

“…For example, Vandenheuvel and Homing (9) observed that gas chromatography of C-21 steroids containing an a-ketol side chain led to side-chain cleavage. Other internal rearrangements of C-2 1 steroids were observed by Brooks (10). Such rearrangements could lead to complications in the quantitation and the a Solvent system : A = cyclohexane-xylene-methanol-triethylamine (400 :400 : 75 : 5) ; B = cyclohexane-toluene-methanol-trimethylamine (400 : 400:75 : 5 ) ; C = cyclohexane-benzene-methanol-trimethylamine (400:400:75 : 5 ) ; D = cyclohexane-benzene-methanol (500: 150:75); E = cyclohexane-benzene-methanol (500 : 150 :75); and F = cyclohexane-benzene-methanol-trimethylamine (500:150:75 :5).…”

“…Since the chromatographic solvent selected for the complete separation of the estrogen mixture was relatively volatile and inert, the separation may be adapted to preparative purposes. An analogous chromatographic system was also found applicable to (2)(3)(4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17)(18)(19)(20)(21) steroid structures containing labile side chains and to steroids that are prone to dehydration under gas chromatographic conditions (15).…”

Novel perfluoroacyl derivatives of corticosteroids and related substances for potential use in quantitative gas chromatography mass spectrometry

“…had a relative intensity of approximately 50% (mass spectrum not presented). We assume that this product indeed contains a 16 double bond, formed by elimination during injection or gas chromatography [4], supported by the generation of a "foot" in the peak front when the final temperature of the injection system was decreased.…”

“…In addition, by thermal or chemical rearrangement, isomeric D-home steroids may be formed that bear the keto group on carbon 17 instead of 17a [3]. Furthermore, during GC, elimination of water can occur, and derivatization of the hydroxyl group sometimes even favors the formation of elimination products [4]. Because of these difficulties, a variety of derivatization procedures for corticosteroids was developed to obtain stable products for GC [5].…”

New derivatives for gas chromatographic and mass spectrometric analysis of some steroid hormones

“…Some of these methods were found to be of no general use. 17 Other derivatives were found to undergo sidechain degradat i~n .~ Furthermore, most of these methods require twostage reaction^,^ which may affect the quantitative results of the analysis." The alkylboronate ester derivatives of the steroids were found to be convenient for qualitative characterization of the steroids by GCMS analysis, but have their own limitations in respect of quantitative analy~is.…”