Triphenylchloroethylene (TPCE; brand names Gynosone, Oestrogyl), or triphenylchlorethylene, also known as chlorotriphenylethylene or as phenylstilbene chloride, is a synthetic

nonsteroidal estrogen A nonsteroidal estrogen is an estrogen with a nonsteroidal chemical structure. The most well-known example is the stilbestrol estrogen diethylstilbestrol (DES). Although nonsteroidal estrogens formerly had an important place in medicine, they hav ...

of the

triphenylethylene Triphenylethylene (TPE) is a simple aromatic hydrocarbon that possesses weak estrogenic activity. Its estrogenic effects were discovered in 1937. TPE was derived from structural modification of the more potent estrogen diethylstilbestrol, which is ...

group that was marketed in the 1940s for the treatment of

menopausal Menopause, also known as the climacteric, is the time in women's lives when Menstruation, menstrual periods stop permanently, and they are no longer fertility, able to bear children. Menopause usually occurs between the age of 47 and 54. Medic ...

symptom Signs and symptoms are the observed or detectable signs, and experienced symptoms of an illness, injury, or condition. A sign for example may be a higher or lower temperature than normal, raised or lowered blood pressure or an abnormality showin ...

s, vaginal atrophy,

lactation suppression Lactation suppression refers to the act of suppressing lactation by medication or other non pharmaceutical means. The breasts may become painful when engorged with milk if breastfeeding is ceased abruptly, or if never started. This may occur if a ...

, and all other

estrogen Estrogen or oestrogen is a category of sex hormone responsible for the development and regulation of the female reproductive system and secondary sex characteristics. There are three major endogenous estrogens that have estrogenic hormonal acti ...

-indicated conditions. The

ic effects of triphenylethylene, the parent compound of triphenylchloroethylene, were discovered in 1937. Triphenylchloroethylene was first reported in 1938 and was found to have 20 to 100 times the estrogenic activity of the relatively weak triphenylethylene, a potentiation of effect that was afforded by its

halogen The halogens () are a group in the periodic table consisting of five or six chemically related elements: fluorine (F), chlorine (Cl), bromine (Br), iodine (I), astatine (At), and tennessine (Ts). In the modern IUPAC nomenclature, this group is ...

substituent A substituent is one or a group of atoms that replaces (one or more) atoms, thereby becoming a moiety in the resultant (new) molecule. (In organic chemistry and biochemistry, the terms ''substituent'' and ''functional group'', as well as ''side ...

. The drug has a relatively long

duration of action Pharmacodynamics (PD) is the study of the biochemical and physiologic effects of drugs (especially pharmaceutical drugs). The effects can include those manifested within animals (including humans), microorganisms, or combinations of organisms (for ...

when administered via

subcutaneous injection Subcutaneous administration is the insertion of medications beneath the skin either by injection or infusion. A subcutaneous injection is administered as a bolus into the subcutis, the layer of skin directly below the dermis and epidermis, ...

but a duration similar to that of

diethylstilbestrol Diethylstilbestrol (DES), also known as stilbestrol or stilboestrol, is a nonsteroidal estrogen medication, which is presently rarely used. In the past, it was widely used for a variety of indications, including pregnancy support for those with a ...

estradiol benzoate Estradiol benzoate (EB), sold under the brand name Progynon-B among others, is an estrogen medication which is used in hormone therapy for menopausal symptoms and low estrogen levels in women, in hormone therapy for transgender women, and in the ...

when administered orally. Along with diethylstilbestrol and triphenylmethylethylene, triphenylchloroethylene was studied in 1944 by

Sir Alexander Haddow Sir Alexander Haddow Royal Society of London, FRS FRSE (18 January 1907 – 21 January 1976) was a Scottish physician and pathologist at the forefront of cancer research in the 1940s. He served as Director of the Institute of Cancer Research fr ...

for the treatment of

breast cancer Breast cancer is cancer that develops from breast tissue. Signs of breast cancer may include a lump in the breast, a change in breast shape, dimpling of the skin, milk rejection, fluid coming from the nipple, a newly inverted nipple, or a re ...

and was found to be significantly effective, and this is historically notable in that it was the first time that high-dose estrogens were found to be effective in the treatment of breast cancer.

Chlorotrianisene Chlorotrianisene (CTA), also known as tri-''p''-anisylchloroethylene (TACE) and sold under the brand name Tace among others, is a nonsteroidal estrogen related to diethylstilbestrol (DES) which was previously used in the treatment of menopausal ...

, or tri-''p''-anisylchloroethylene (TACE), is a potent marketed estrogen and a

derivative In mathematics, the derivative of a function of a real variable measures the sensitivity to change of the function value (output value) with respect to a change in its argument (input value). Derivatives are a fundamental tool of calculus. F ...

of triphenylchloroethylene in which each of the three

phenyl ring In organic chemistry, the phenyl group, or phenyl ring, is a cyclic group of atoms with the formula C6 H5, and is often represented by the symbol Ph. Phenyl group is closely related to benzene and can be viewed as a benzene ring, minus a hydrogen ...

s has been substituted with a 4-

methoxy group In organic chemistry, a methoxy group is the functional group consisting of a methyl group bound to oxygen. This alkoxy group has the formula . On a benzene ring, the Hammett equation classifies a methoxy substituent at the ''para'' position as ...

Estrobin Estrobin, also known as α,α-di(''p''-ethoxyphenyl)-β-phenylbromoethylene and commonly abbreviated as DBE, is a Organic compound#Synthetic compounds, synthetic, nonsteroidal estrogen of the triphenylethylene group that was never marketed. Chlor ...

, or DBE, is a related, never-marketed estrogen in which there is a

bromine Bromine is a chemical element with the symbol Br and atomic number 35. It is the third-lightest element in group 17 of the periodic table (halogens) and is a volatile red-brown liquid at room temperature that evaporates readily to form a simila ...

in place of the

chlorine Chlorine is a chemical element with the Symbol (chemistry), symbol Cl and atomic number 17. The second-lightest of the halogens, it appears between fluorine and bromine in the periodic table and its properties are mostly intermediate betwee ...

and two of the three phenyl rings have ethoxy groups. Broparestrol, or BDPE is a marketed

selective estrogen receptor modulator Selective estrogen receptor modulators (SERMs), also known as estrogen receptor agonist/antagonists (ERAAs), are a class of drugs that act on the estrogen receptor (ER). A characteristic that distinguishes these substances from pure ER agonists a ...

(SERM) that has a bromine in place of the chlorine of triphenylchloroethylene and a 4-

ethyl group In organic chemistry, an ethyl group (abbr. Et) is an alkyl substituent with the formula , derived from ethane (). ''Ethyl'' is used in the International Union of Pure and Applied Chemistry's nomenclature of organic chemistry for a saturated ...

on one of the phenyl rings. The SERM

clomifene Clomifene, also known as clomiphene, is a medication used to treat infertility in women who do not ovulate, including those with polycystic ovary syndrome. Use results in a greater chance of twins. It is taken by mouth once a day, with a course ...

is also a derivative of triphenylchloroethylene.

References

Abandoned drugs Hormonal antineoplastic drugs Organochlorides Synthetic estrogens Triphenylethylenes {{antineoplastic-drug-stub

See also

References