[21-C-11]Progesterone was synthesised via the cross-coupling 17 beta-c
arboxylic acid chloride-4-androsten-3-one with lithium [C-11]methyl(2-
thienyl)cuprate (LiCN). The title compound was obtained in 30-35% deca
y corrected radiochemical yield, based on [C-11]methyl iodide, within
35 minutes after end of radionuclide production. The specific radioact
ivity was 14 GBq/mu mole. (21-C-13)Progesterone vias synthesised using
the same procedure for determination of the position of the label.