title: 11 beta,20-dihydroxy-3-oxopregna-4,17(20)-dien-21-al: an intermediate in the biological 17-dehydroxylation of cortisol.
abstract: The role of 11 beta,20-dihydroxy-3-oxopregna-4,17(20)-dien-21-al (F enol aldehyde) as an intermediate in the biological conversion of cortisol to a 17-deoxy-21-oic acid was studied in vitro with mouse liver as the source of enzyme. The substrate, [1,2-3H]F enol aldehyde, was synthesized and found to contain cis and trans isomeric forms in a ratio of approximately 3:1. Tritium labeled F enol aldehyde was incubated with mouse liver homogenates. The metabolic products were analyzed by TLC and HPLC. 11 beta,20-Dihydroxy-3-oxopregna-4-en-21-oic acid, a 17-deoxy-21-oic acid, was identified as a quantitatively significant metabolite of the cis isomer. Metabolic conversion of the trans isomer to acid metabolites did not occur. The results are consistent with our hypothesis that the metabolic 17-dehydroxylation of cortisol requires an enol aldehyde intermediate and indicate that the conversion of the enol aldehyde to hydroxy acid is stereospecific.
mesh_terms: D000818:Animals; D002851:Chromatography, High Pressure Liquid; D002855:Chromatography, Thin Layer; D006854:Hydrocortisone / Q000378:metabolism*; D007536:Isomerism; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D011244:Pregnadienediols / Q000378:metabolism*
chemical_list: D011244:Pregnadienediols; C049823:11,20-dihydroxy-3-oxopregna-4,17(20)-dien-21-al; D006854:Hydrocortisone