A 17α-alkylated anabolic steroid is a synthetic anabolic–androgenic steroid (AAS) that features an alkyl group , specifically a methyl or ethyl group , at the C17α position. Unlike many other AAS, 17α-alkylated AAS are orally active and do not require intramuscular injection . However, they uniquely possess a high potential for hepatotoxicity , which simultaneously limits their use. In addition, some have a high risk of gynecomastia due to uniquely high estrogenic activity, although this does not apply to 17α-alkylated AAS that are also 4,5α-reduced or 19-demethylated (i.e., that are also dihydrotestosterone (DHT) or nandrolone derivatives, respectively). The prototypical example of a 17α-alkylated AAS is methyltestosterone (17α-methyltestosterone).
Structure-activity relationships
Extension of the C17α alkyl chain longer than an ethyl group abolishes androgenic activity and converts the drug into an antiandrogen , as in topterone (17α-propyltestosterone) and allylestrenol (17α-allyl-3-deketo-19-nortestosterone) (an extended-chain variant of ethylestrenol ). Conversely, replacement of the C17α alkyl group with an ethynyl group greatly reduces but does not abolish androgenic activity, as in ethisterone (17α-ethynyltestosterone) and norethisterone (17α-ethynyl-19-nortestosterone).[ 1] Similarly to extension of the C17α alkyl chain, extension of the C17α ethynyl chain abolishes androgenic activity, as with dimethisterone (6α,21-dimethylethisterone). Dienogest , which is antiandrogenic, features extension of the C17α chain in the form of a cyanomethyl group at the C17α position.
List of 17α-alkylated AAS
Testosterone derivatives
Dihydrotestosterone derivatives
Nandrolone (19-nortestosterone) derivatives
See also
References
Androgens (incl. AAS Tooltip anabolic–androgenic steroid )
AR Tooltip Androgen receptor agonists
Testosterone derivatives: Androstenediol dipropionate
Boldenone undecylenate
Clostebol
Clostebol acetate
Clostebol caproate
Clostebol propionate
Cloxotestosterone acetate
Prasterone (dehydroepiandrosterone, DHEA)
Prasterone enanthate (DHEA enanthate)
Prasterone sulfate (DHEA sulfate)
Quinbolone
Testosterone #
Testosterone esters (e.g., testosterone cypionate , testosterone enanthate , testosterone propionate , testosterone undecanoate , testosterone ester mixtures (Deposterona , Omnadren , Sustanon , Testoviron Depot ))
Dihydrotestosterone derivatives: Androstanolone (stanolone, dihydrotestosterone, DHT)
Androstanolone esters
Bolazine capronate
Drostanolone propionate (dromostanolone propionate)
Epitiostanol
Mepitiostane
Mesterolone
Metenolone acetate (methenolone acetate)
Metenolone enanthate (methenolone enanthate)
Stenbolone acetate
19-Nortestosterone derivatives: Bolandiol dipropionate
Nandrolone esters (e.g., nandrolone decanoate , nandrolone phenylpropionate )
Norclostebol
Norclostebol acetate
Oxabolone cipionate (oxabolone cypionate)
Trenbolone acetate
Trenbolone hexahydrobenzylcarbonate (trenbolone cyclohexylmethylcarbonate)
17α-Alkylated testosterone derivatives: Bolasterone
Calusterone
Chlorodehydromethyltestosterone (CDMT)
Fluoxymesterone
Formebolone
Metandienone (methandienone, methandrostenolone)
Methandriol (methylandrostenediol)
Methandriol bisenanthoyl acetate
Methandriol dipropionate
Methandriol propionate
Methyltestosterone
Methyltestosterone 3-hexyl ether
Oxymesterone
Penmesterol
Tiomesterone (thiomesterone)
17α-Alkylated dihydrotestosterone derivatives: Androisoxazole
Furazabol
Mebolazine (dimethazine)
Mestanolone
Oxandrolone
Oxymetholone
Stanozolol
17α-Alkylated 19-nortestosterone derivatives: Ethylestrenol
Mibolerone
Norethandrolone
Normethandrone (methylestrenolone, normethisterone)
Propetandrol (propethandrol)
17α-Vinyltestosterone derivatives: Norvinisterone (vinylnortestosterone)
17α-Ethynyltestosterone derivatives: Danazol
Gestrinone
Progestins (e.g., ethisterone (ethynyltestosterone) , levonorgestrel , norgestrel , norethisterone (norethindrone) , lynestrenol , norgestrienone )
Tibolone
Progesterone derivatives: Medroxyprogesterone acetate
Progonadotropins
Antiandrogens
AR Tooltip Androgen receptor antagonists Steroidogenesis inhibitors
Antigonadotropins
D2 receptor antagonists (prolactin releasers ) (e.g., domperidone , metoclopramide , risperidone , haloperidol , chlorpromazine , sulpiride )
Estrogens (e.g., bifluranol , diethylstilbestrol , estradiol , estradiol esters , ethinylestradiol , ethinylestradiol sulfonate , paroxypropione )
GnRH agonists (e.g., leuprorelin )
GnRH antagonists (e.g., cetrorelix )
Progestogens (incl., chlormadinone acetate , cyproterone acetate , hydroxyprogesterone caproate , gestonorone caproate , medroxyprogesterone acetate , megestrol acetate )
Others
AR Tooltip Androgen receptor
Agonists
Testosterone derivatives: 4-Androstenediol
4-Dehydroepiandrosterone (4-DHEA)
4-Hydroxytestosterone
4,17α-Dimethyltestosterone
5-Androstenedione
11-Ketotestosterone
11β-Hydroxyandrostenedione
Adrenosterone (11-ketoandrostenedione, 11-oxoandrostenedione)
Androstenediol (5-androstenediol)
Androstenedione (4-androstenedione)
Atamestane
Boldenone
Boldione (1,4-androstadienedione)
Clostebol
Cloxotestosterone
Dehydroandrosterone
DHEA (androstenolone, prasterone; 5-DHEA)
Exemestane
Formestane
Plomestane
Quinbolone
Silandrone
Testosterone # (+dutasteride )
5α-Dihydrotestosterone derivatives: 1-Androstenediol
1-Androstenedione
1-Androsterone (1-andro, 1-DHEA)
1-Testosterone
3α-Androstanediol
5α-Androst-2-en-17-one
7β-Hydroxyepiandrosterone
11-Ketodihydrotestosterone
Androsterone
Bolazine
Dihydroethyltestosterone
Dihydrofluoxymesterone
Dihydromethylandrostenediol
Dihydrotestosterone (DHT) (androstanolone, stanolone )
Drostanolone
Epiandrosterone
Epitiostanol
Mepitiostane
Mesabolone
Mesterolone
Methyldiazinol
Nisterime
Prostanozol
Stenbolone
Testifenon (testiphenon, testiphenone)
19-Nortestosterone derivatives: 7α-Methyl-19-norandrostenedione (MENT dione, trestione)
11β-Methyl-19-nortestosterone
19-Nor-5-androstenediol
19-Nor-5-androstenedione
19-Nordehydroepiandrosterone
Bolandiol
Bolandione (19-nor-4-androstenedione)
Bolmantalate (nandrolone adamantoate)
Dienedione
Dienolone
Dimethandrolone
LS-1727 (nandrolone 17β-N -(2-chloroethyl)-N -nitrosocarbamate)
Methoxydienone (methoxygonadiene)
Nandrolone
Norclostebol
Normethandrone (methylestrenolone, normethisterone)
Oxabolone
Trenbolone
Trendione
Trestolone (MENT)
5α-Dihydro-19-nortestosterone derivatives: 5α-Dihydronandrolone
5α-Dihydrotrestolone
19-Norandrosterone
17α-Alkylated testosterone derivatives: Bolasterone
Calusterone
Chlorodehydromethylandrostenediol (CDMA)
Chlorodehydromethyltestosterone (CDMT)
Chloromethylandrostenediol (CMA)
Enestebol
Ethyltestosterone
Fluoxymesterone
Formebolone
Hydroxystenozole
Metandienone (methandrostenolone)
Methandriol (methylandrostenediol)
Methylclostebol (chloromethyltestosterone)
Methyltestosterone (+esterified estrogens )
Oxymesterone
Penmesterol
Tiomesterone
17α-Alkylated 5α-dihydrotestosterone derivatives: Androisoxazole
Desoxymethyltestosterone
Furazabol
Mebolazine (dimethazine)
Mestanolone
Metenolone
Methasterone
Methyl-1-testosterone
Methylepitiostanol
Methylstenbolone
Oxandrolone
Oxymetholone
Stanozolol
17α-Alkylated 19-nortestosterone derivatives: Bolenol
Dimethyldienolone
Dimethyltrienolone
Ethyldienolone
Ethylestrenol
Methyldienolone
Methylhydroxynandrolone (MOHN, MHN)
Metribolone
Mibolerone
Norboletone
Norethandrolone
Propetandrol
RU-2309
Tetrahydrogestrinone
17α-Alkylated 5α-dihydro-19-nortestosterone derivatives: 5α-Dihydronorethandrolone
5α-Dihydronormethandrone
17α-Vinyltestosterone derivatives: Norvinisterone (vinylnortestosterone)
17α-Vinyl-19-nortestosterone derivatives: Vinyltestosterone
17α-Ethynyltestosterone derivatives: Danazol
Ethinylandrostenediol
Ethisterone (ethynyltestosterone)
5α-Dihydro-17α-ethynyltestosterone derivatives: 17α-Ethynyl-3α-androstanediol
17α-Ethynyl-3β-androstanediol
Dihydroethisterone
17α-Ethynyl-19-nortestosterone derivatives: Δ4 -Tibolone
Desogestrel
Etonogestrel
Etynodiol
Gestodene
Gestrinone
Levonorgestrel
Levonorgestrel esters (e.g., levonorgestrel butanoate )
Lynestrenol
Norethisterone
Norethisterone esters (e.g., norethisterone acetate , norethisterone enanthate )
Norgestrel
Norgestrienone
Quingestanol
Tibolone
5α-Dihydro-17α-ethynyl-19-nortestosterone derivatives: 5α-Dihydrolevonorgestrel
5α-Dihydronorethisterone
Progesterone derivatives: 6α-Methylprogesterone
Medroxyprogesterone acetate
Megestrol acetate
Others/unsorted: 3-Keto-5α-abiraterone
5α-Androstane
Alternariol
Cl-4AS-1
Drupanol
Trilostane
ZM-182345
SARMs Tooltip Selective androgen receptor modulator Antagonists
GPRC6A