17α-Ethynyl-3β-androstanediol (developmental code HE-3539; also known as 17α-ethynyl-5α-androstane-3β,17β-diol) is a

synthetic Synthetic may refer to: Science * Synthetic biology * Synthetic chemical or compound, produced by the process of chemical synthesis * Synthetic elements, chemical elements that are not naturally found on Earth and therefore have to be created in ...

estrogen Estrogen (also spelled oestrogen in British English; see spelling differences) is a category of sex hormone responsible for the development and regulation of the female reproductive system and secondary sex characteristics. There are three ...

and a 17α-substituted

derivative In mathematics, the derivative is a fundamental tool that quantifies the sensitivity to change of a function's output with respect to its input. The derivative of a function of a single variable at a chosen input value, when it exists, is t ...

of 3β-androstanediol which was never marketed. 17α-Ethynyl-3β-androstanediol shows high

affinity Affinity may refer to: Commerce, finance and law * Affinity (law), kinship by marriage * Affinity analysis, a market research and business management technique * Affinity Credit Union, a Saskatchewan-based credit union * Affinity Equity Pa ...

for the

estrogen receptor Estrogen receptors (ERs) are proteins found in cell (biology), cells that function as receptor (biochemistry), receptors for the hormone estrogen (17β-estradiol). There are two main classes of ERs. The first includes the intracellular estrogen ...

s ''

in vitro ''In vitro'' (meaning ''in glass'', or ''in the glass'') Research, studies are performed with Cell (biology), cells or biological molecules outside their normal biological context. Colloquially called "test-tube experiments", these studies in ...

'' ( values of 16 nM for

ERα Estrogen receptor alpha (ERα), also known as NR3A1 (nuclear receptor subfamily 3, group A, member 1), is one of two main types of estrogen receptor, a nuclear receptor (mainly found as a chromatin-binding protein) that is activated by the se ...

and 126 nM for

ERβ Estrogen receptor beta (ERβ) also known as NR3A2 (nuclear receptor subfamily 3, group A, member 2) is one of two main types of estrogen receptor—a nuclear receptor which is activated by the sex hormone estrogen. In humans ERβ is encoded by t ...

relative to values of 8 nM at ERα and 7 nM at ERβ for

estradiol Estradiol (E2), also called oestrogen, oestradiol, is an estrogen steroid hormone and the major female sex hormone. It is involved in the regulation of female reproductive cycles such as estrous and menstrual cycles. Estradiol is responsible ...

), and activates the estrogen receptors ''in vitro'' ( value of 0.9 nM relative to 0.002 nM for estradiol). It also has weak affinity for the

androgen receptor The androgen receptor (AR), also known as NR3C4 (nuclear receptor subfamily 3, group C, member 4), is a type of nuclear receptor that is activated by binding any of the androgenic hormones, including testosterone and dihydrotestosterone, in th ...

''in vitro'' (IC₅₀ = 277 nM relative to 15 nM for

dihydrotestosterone Dihydrotestosterone (DHT, 5α-dihydrotestosterone, 5α-DHT, androstanolone or stanolone) is an endogenous androgen sex steroid and hormone primarily involved in the growth and repair of the prostate and the penis, as well as the production o ...

), but doesn't appear to activate the receptor. 17α-Ethynyl-3β-androstanediol may produce 17α-ethynyl-3α-androstanediol and

5α-dihydroethisterone 5α-Dihydroethisterone (5α-DHET; developmental code name HE-3562) is an active metabolite of the formerly clinically used but now-discontinued progestin ethisterone and the experimental and never-marketed hormonal antineoplastic agent ethynyla ...

(5α-dihydro-17α-ethynyltestosterone) as

active metabolite An active metabolite, or pharmacologically active metabolite is a biologically active metabolite of a xenobiotic substance, such as a drug or environmental chemical. Active metabolites may produce therapeutic effects, as well as harmful effects. ...

s ''

in vivo Studies that are ''in vivo'' (Latin for "within the living"; often not italicized in English) are those in which the effects of various biological entities are tested on whole, living organisms or cells, usually animals, including humans, an ...

''. In accordance with its ''in-vitro'' estrogenic activity, 17α-ethynyl-3β-androstanediol produces estrogenic effects like

uterotrophy The uterus (from Latin ''uterus'', : uteri or uteruses) or womb () is the organ in the reproductive system of most female mammals, including humans, that accommodates the embryonic and fetal development of one or more fertilized eggs until bir ...

and

testicular atrophy Testicular atrophy is a medical condition in which one or both testicles (or "testes") diminish in size and may be accompanied by reduced testicular function. Testicular atrophy is not related to the temporary shrinkage of the surrounding scrotum, ...

in animals.

Ester In chemistry, an ester is a compound derived from an acid (either organic or inorganic) in which the hydrogen atom (H) of at least one acidic hydroxyl group () of that acid is replaced by an organyl group (R). These compounds contain a distin ...

s of 17α-ethynyl-3β-androstanediol have been developed and studied. 17α-Ethynyl-3β-androstanediol is a

positional isomer In chemistry, a structural isomer (or constitutional isomer in the IUPAC nomenclature) of a compound is a compound that contains the same number and type of atoms, but with a different connectivity (i.e. arrangement of bonds) between them. The ...

of 17α-ethynyl-3α-androstanediol, and is a metabolite of this compound ''

'' via

metabolic Metabolism (, from ''metabolē'', "change") is the set of life-sustaining chemical reactions in organisms. The three main functions of metabolism are: the conversion of the energy in food to energy available to run cellular processes; the ...

inversion of the position of the C3

hydroxyl group In chemistry, a hydroxy or hydroxyl group is a functional group with the chemical formula and composed of one oxygen atom covalently bonded to one hydrogen atom. In organic chemistry, alcohols and carboxylic acids contain one or more hydroxy ...

. It may be involved in the

biological activity In pharmacology, biological activity or pharmacological activity describes the beneficial or adverse effects of a drug on living matter. When a drug is a complex chemical mixture, this activity is exerted by the substance's active ingredient or ...

of 17α-ethynyl-3α-androstanediol.

Analogues

Analogues of 17α-ethynyl-3β-androstanediol include 17α-ethynyl-3α-androstanediol,

ethinylandrostenediol Ethinylandrostenediol (developmental code name SKF-2856), also known as 17α-ethynyl-5-androstenediol, is a synthetic estrogen, progestogen, and androgen which was never marketed. It is the C17α ethynyl derivative of the androgen precursor and ...

(17α-ethynyl-5-androstenediol),

ethandrostate Ethandrostate, also known as ethinylandrostenediol 3β-cyclohexanepropionate, is a synthetic steroidal estrogen and ester of ethinylandrostenediol (17α-ethynyl-5-androstenediol) which was developed and studied in people with certain cancers lik ...

(17α-ethynyl-5-androstenediol 3β-cyclohexanepropionate),

ethinylestradiol Ethinylestradiol (EE) is an estrogen medication which is used widely in birth control pills in combination with progestins. Ethinylestradiol was widely used for various indications such as the treatment of menopausal symptoms, gynecological ...

(17α-ethynylestradiol),

ethisterone Ethisterone, also known as ethinyltestosterone, pregneninolone, and anhydrohydroxyprogesterone and formerly sold under the brand names Proluton C and Pranone among others, is a progestin medication which was used in the treatment of gynecologica ...

(17α-ethynyltestosterone), and

(17α-ethynyldihydrotestosterone).

References

{{DEFAULTSORT:Ethynyl-3β-androstanediol, 17α- 5α-Reduced steroid metabolites Abandoned drugs Ethynyl compounds Androstanes Antigonadotropins Diols Human drug metabolites Synthetic estrogens