Gas-liquid chromatographic studies of reactions and structural relationships of steroids : Part I. Positions 3, 11 and 17 in the androstane series

Abstract

Qualitative and quantitative effects of classical reactions on steroids observed by gas-liquid chromatography (GLC) under standardized conditions, including the double internal standard techique, are reported. Simple procedures, applicable to nanogram amounts of reactants, that afford excellent yields of the major products are described. Reactions studied include the Wolff-Kishner removal of keto groups (WK), their conversion into hydroxyl groups with sodium borohydride and into dioxolone derivatives with ethylene glycol: the conversion of hydroxyl into keto groups with chromium trioxide and into trimethylsilyl (TMS) ethers with hexamethyldisilazane: and the hydrolysis of dioxolone and TMS derivatives with H +. Gas-liquid chromatograms of reaction mixtures of singe- and multi-step reactions readily provide information on the effects on functional groups at positions 3, 11 and 17 in the androstane series and the retention times of many steroids unavailable from commercial or other sources. GLC data analysis provides relationships between steroid structure and retention times, from which methods for the calculation of retention times and for steroid identification are designed. The accuracy of the calculation methods is demonstrated and conditions for their efficient application are discussed.