title: Synthesis of 2',2'-difluoro-6,7-dihydro-16-methylenecyclopropa(6,7)progesterone analogues.
mesh_terms: D003521:Cyclopropanes / Q000138:chemical synthesis; D005461:Fluorine; D006868:Hydrolysis; D008722:Methods; D011245:Pregnadienes; D011374:Progesterone / Q000138:chemical synthesis*; D011372:Progestins / Q000138:chemical synthesis; D013329:Structure-Activity Relationship
chemical_list: D003521:Cyclopropanes; D011245:Pregnadienes; D011372:Progestins; D005461:Fluorine; D011374:Progesterone