1164-81-4 4-07-00-02399 (Beilstein Handbook Reference) 4-Chlor-progesterone 4-Chloropregn-4-ene-3,20-dione 4-Chloroprogesterone BRN 3105722 NSC 18308 Pregn-4-ene-3,20-dione, 4-chloro-