Progestins Overall Organization of the Topic Structure and function of natural progestin - Progesterone Nomenclature of progestational steroids Biosynthesis and metabolism of progesterone Progesterone Agonists Generalizations on Structure-Activity Relationships Progesterone antagonist - RU-486 2/23/2019 MEDC 603 Steroids

Progestins Progest-4-ene-3,20-dione Progesterone 2/23/2019 MEDC 603 Steroids

Inhibits follicular maturation and ovulation Functions of Progesterone Maintains pregnancy Inhibits follicular maturation and ovulation prevents spontaneous uterine contraction 2/23/2019 MEDC 603 Steroids

Progesterone Metabolism Reduction C-20 Reduction C-4, C-3 Reduction C-20 Reduction C-4, C-3 2/23/2019 MEDC 603 Steroids

Progesterone Agonists 1. Derivatization of the 17 - position 17a-hydroxyprogesterone caproate Click here to view the 3D structure of 17-substitution 2/23/2019 MEDC 603 Steroids

Medroxyprogesterone acetate Progesterone Agonists 2. Derivatization of A/B rings Medroxyprogesterone acetate (Oral Activity = 12-25) Megestrol acetate Chlomadinone acetate 2/23/2019 MEDC 603 Steroids

Progesterone Agonists 3. Testosterone Derivatives Ethisterone Dimethisterone Relative Oral Activity = 1 Relative Oral Activity = 12 2/23/2019 MEDC 603 Steroids

Progesterone Agonists 4. 19-Nortestosterone Derivatives Norethindrone Norgestrel Relative Oral Activity = 5-10 2/23/2019 MEDC 603 Steroids

Either a progesterone or a testosterone skeleton Generalizations on Structure-Activity Relationships for Oral Progestational Activity Steroid skeleton Unsaturated A ring Either a progesterone or a testosterone skeleton If testosterone derivative, 17-ethinyl substitution 19-nor substitution is useful 2/23/2019 MEDC 603 Steroids

Progesterone Antagonist RU-486: Mifepristone 2/23/2019 MEDC 603 Steroids