Collect. Czech. Chem. Commun. 1991, 56, 1087-1092

Synthesis of (19E)-3,20-dioxopregn-4-en-19-al 19-(O-carboxymethyl)oxime

Jan Fajkoša, Vladimír Pouzara and Karel Verešb

a Institute of Organic Chemistry and Biochemistry, Czechoslovak Academy of Sciences, 166 10 Prague 6
b Institute of Nuclear Biology and Radiochemistry, Czechoslovak Academy of Sciences, 142 20 Prague 4


Hydride reduction of the ketone I gave the (20R)-hydroxy derivative II. Cleavage of the diacetate III with zinc dust, followed by mild Jones’ oxidation led to the aldehyde V. Oximation with (O-carboxymethyl)hydroxylamine hemihydrochloride and methylation with diazomethane afforded the ester VI. Alkaline hydrolysis to the acid catalyzed rearrangement afforded the dione IX. Mild hydrolysis gave the desired hapten X derived from progesterone.