Gas-liquid chromatographic studies of reactions and structural relationships of steroids : V. concurrent substitution in the pregnane side-chain and position 11

Abstract

Qualitative and quantitative effects of classical reactions on steroids observed by gas-liquid chromatography (GLC) under standardized conditions, including the double internal standard technique, are reported. Simple procedures applicable to nanogram amounts of reactants are described. Reactions studied include the conversion of keto groups to hydroxyl groups by NaBH 4, and the removal of the pregnane side-chain with NaBiO 3. GLC chromatograms readily provide information on effects on functional groups at positions 3, 11, 17, 20, and 21 and the retention times of many steroids unavailable from commercial sources. GLC data analysis provides relationships between steroid structure and retention time from which methods for the computation of retention times and steroid identification are designed. The accuracy of these methods is demonstrated.