(16alpha)-21-(Fluoro-18F)-16-methyl-19-norpregn-4-ene-3,20-dione 134785-66-3 19-Norpregn-4-ene-3,20-dione, 21-(fluoro-18F)-16-methyl-, (16alpha)- 21-Fluoro-16-methyl-19-norprogesterone 21-Fmnp