Title: Gestrinone
CAS Registry Number: 16320-04-0
CAS Name: (17a)-13-Ethyl-17-hydroxy-18,19-dinorpregna-4,9,11-trien-20-yn-3-one
Additional Names: 13b-ethyl-17a-ethynyl-17b-hydroxy-4,9,11-gonatrien-3-one; 13b-ethyl-17a-ethynyl-D4,9,11-gonatriene-17b-ol-3-one; ethylnorgestrienone
Manufacturers' Codes: A-46745; R-2323; RU-2323
Trademarks: Dimetriose (HMR); Dimetrose (Poli); Nemestran (HMR); Tridomose (HMR)
Molecular Formula: C21H24O2
Molecular Weight: 308.41
Percent Composition: C 81.78%, H 7.84%, O 10.38%
Literature References: Steroidal antiestrogen, antiprogestogen, analog of norgestrienone, q.v. Prepn: G. Nomine et al., US 3257278; NL 6607609 C.A. 67, 44029d (1967); D. Bertin, A. Pierdet, US 3478067 (1966, 1966, 1969 all to Roussel-UCLAF). Radioimmunoassay in human plasma: J. Frick et al., Urol. Res. 5, 55 (1977). HPLC-MS-MS determn in plasma: Q. Wang et al., J. Chromatogr. B 746, 151 (2000). Clinical evaluation of contraceptive efficacy: G. Azadian-Boulanger et al., Am. J. Obstet. Gynecol. 125, 1049 (1976); of use in fibrocystic breast disease: E. M. Coutinho, G. Azadian-Boulanger, Int. J. Gynaecol. Obstet. 22, 363 (1984); in endometriosis: E. J. Thomas, I. D. Cooke, Br. Med. J. 294, 272 (1987); E. M. Coutinho, G. Azadian-Boulanger, Fertil. Steril. 49, 418 (1988).
Properties: Crystals from ethyl acetate and benzene-cyclohexane (1:1), mp 154°. [a]D20 +84.6° (c = 0.41 in methanol).
Melting point: mp 154°
Optical Rotation: [a]D20 +84.6° (c = 0.41 in methanol)
Therap-Cat: Antigonadotropin.
Keywords: Antigonadotropin.
Ghatti Gum Ghi Gibberellic Acid Gibberellins Gibbs Reagent

Systematic (IUPAC) name
13-ethyl-17alpha-hydroxy-18,19 dinorpregna-4,9,11-trien-20-yn-3-one
Clinical data
AHFS/ International Drug Names
Pregnancy cat. X
Legal status  ?
Routes Oral, Intravaginal
Pharmacokinetic data
Metabolism Hepatic
Excretion Renal, fecal
CAS number 16320-04-0
ATC code G03XA02
PubChem CID 27812
ChemSpider 25877 YesY
UNII 1421533RCM YesY
KEGG D04317 YesY
Chemical data
Formula C21H24O2 
Mol. mass 308.41 g/mol
 YesY (what is this?)  (verify)

Gestrinone is a synthetic steroid hormone that acts as an anti-progestin and also has some androgenic activity. It is marketed under the names Dimetriose, Dimetrose, and Nemestran, as a treatment for endometriosis. Gestrinone is available in many countries, but not in the USA. As it has anabolic effects, its use in competition has been banned by the International Olympic Committee.[1]