title: Conversion of an androgen epoxide into 17beta-estradiol by human placental microsomes.
abstract: Three androgen epoxides, 17beta-hydroxy-4beta,5-oxido-5beta-androstan-3-one (II), 3beta,19-dihydroxy-5,6beta-oxido-5beta-androstan-17-one 3-acetate (VIII), and 19-hydroxy-4beta,5-oxido-5beta-androstane-3,17-dione (V), were synthesized and subsequently evaluated as potential precursors in the biosynthesis of estrogens by incubation with human placental microsomes. One of these epoxides (V) was converted into 17beta-estradiol, whereas the other two were metabolized to unidentified products. The possible intermediacy of an androgen epoxide in the biosynthesis of estrone and of 17beta-estradiol is discussed and a mechanism is proposed for the aromatization process.
mesh_terms: D000728:Androgens / Q000138:chemical synthesis / Q000378:metabolism*; D000731:Androstanes / Q000378:metabolism; D000738:Androsterone / Q000031:analogs & derivatives / Q000378:metabolism; D013196:Dihydrotestosterone / Q000378:metabolism; D004852:Epoxy Compounds / Q000378:metabolism; D004958:Estradiol / Q000096:biosynthesis*; D004970:Estrone / Q000096:biosynthesis; D005260:Female; D006801:Humans; D008861:Microsomes / Q000378:metabolism*; D010920:Placenta / Q000378:metabolism*; D011247:Pregnancy; D013329:Structure-Activity Relationship
chemical_list: D000728:Androgens; D000731:Androstanes; D004852:Epoxy Compounds; D013196:Dihydrotestosterone; D004970:Estrone; D004958:Estradiol; D000738:Androsterone