19-Norpregn-4-ene-3,20-dione, 4-chloro- 4-07-00-02390 (Beilstein Handbook Reference) 4-Chloro-19-norpregn-4-ene-3,20-dione 4-Chloro-19-norprogesterone 99950-46-6 BRN 3160642