17α-hydroxy-19-norpregna-5(10),9(11)-diene-3,20-dione 3,20-bis(ethylene acetal)
3,3-[1,2-ethanediylbis(oxy)]-17α-hydroxy-19-norpregna-5(10),9(11)-diene-20-one
3,3,20,20-bis(ethylene-dioxy)-5α-17α-dihydroxy-11β-[4-(N,N-dimethylamino)-phenyl-]-19-norpregna-9(11)-ene
5α,10α-epoxy-17α-hydroxy-19-norpregn-9(11)-ene-3,20-dione 3,20-bis(ethylene acetal)
ulipristal acetate