Title: Clomiphene
CAS Registry Number: 911-45-5
CAS Name: 2-[4-(2-Chloro-1,2-diphenylethenyl)phenoxy]-N,N-diethylethanamine
Additional Names: 2-[p-(2-chloro-1,2-diphenylvinyl)phenoxy]triethylamine; 2-[p-(b-chloro-a-phenylstyryl)phenoxy]triethylamine; 1-[p-(b-diethylaminoethoxy)phenyl]-1,2-diphenylchloroethylene; clomifene; chloramiphene
Manufacturers' Codes: MRL-41; WSM-5008
Molecular Formula: C26H28ClNO
Molecular Weight: 405.96
Percent Composition: C 76.92%, H 6.95%, Cl 8.73%, N 3.45%, O 3.94%
Literature References: Synthetic estrogen agonist-antagonist. Prepn: R. E. Allen et al., US 2914563 (1959 to Merrell); F. P. Palopoli et al., J. Med. Chem. 10, 84 (1967). Stereochemistry of the geometric isomers: Ernst et al., J. Pharm. Sci. 65, 148 (1976). Induction of ovulation: R. B. Greenblatt, Fertil. Steril. 12, 402 (1961). Clinical trial in anovulatory women: J. Garcia et al., ibid. 28, 707 (1977). Use in male infertility: P. J. Sorbie, R. Perez-Marrero, J. Urol. 131, 425 (1984). HPLC determn of isomers in human plasma: C. L. Baustian, T. J. Mikkelson, J. Pharm. Biomed. Anal. 4, 237 (1986). Review of development, pharmacology and clinical experience: R. P. Dickey, D. E. Holtkamp, Hum. Reprod. Update 2, 483-506 (1996).
Derivative Type: Citrate
CAS Registry Number: 50-41-9
Trademarks: Clomid (Aventis); Clostilbegyt (Egis); Pergotime (Serono); Serofene (Serono); Serophene (Serono)
Molecular Formula: C26H28ClNO.C6H8O7
Molecular Weight: 598.08
Percent Composition: C 64.26%, H 6.07%, Cl 5.93%, N 2.34%, O 21.40%
Properties: Crystals, mp 116.5-118°. Slightly sol in water, chloroform; freely sol in methanol; sparingly sol in alcohol. Insol in ether.
Melting point: mp 116.5-118°
Derivative Type: cis-Form
CAS Registry Number: 15690-55-8
Additional Names: Zuclomiphene
Properties: Hydrochloride salt mp 156.5-158.0°. uv max (methanol): 230, 291 nm (e 20500, 12700).
Melting point: mp 156.5-158.0°
Absorption maximum: uv max (methanol): 230, 291 nm (e 20500, 12700)
Derivative Type: trans-Form
CAS Registry Number: 15690-57-0
Additional Names: Enclomiphene
Properties: Hydrochloride salt mp 149.0-150.5°. uv max (methanol): 239, 297 nm (e 22100, 11600).
Melting point: mp 149.0-150.5°
Absorption maximum: uv max (methanol): 239, 297 nm (e 22100, 11600)
Therap-Cat: Gonad-stimulating principle.
Keywords: Gonad-Stimulating Principle.
Clomipramine Clomocycline Clonazepam Clonidine Clonitazene

Systematic (IUPAC) name
Clinical data
AHFS/ Micromedex Detailed Consumer Information
Pregnancy cat. B3 (Au), X (U.S.)
Legal status S4 (Au), POM (UK), ℞-only (U.S.)
Routes per os
Pharmacokinetic data
Bioavailability High (>90%)
Metabolism Hepatic (with enterohepatic circulation)
Half-life 5-7 days
Excretion Mainly renal, some biliary
CAS number 911-45-5 YesY
ATC code G03GB02
PubChem CID 2800
DrugBank DB00882
ChemSpider 2698 YesY
KEGG D07726 YesY
Chemical data
Formula C26H28ClNO 
Mol. mass 406 or 598.10 (with citrate)
 N (what is this?)  (verify)

Clomifene (INN) or clomiphene (USAN) (trademarked as Androxal, Clomid and Omifin) is a selective estrogen receptor modulator (SERM) that increases production of gonadotropins by inhibiting negative feedback on the hypothalamus. This synthetic drug comes supplied as white, round tablets in 50 mg strength only. It has become the most widely prescribed of all fertility drugs. It is used in the form of its citrate to induce ovulation.