3α-Androstanediol

3α-Androstanediol also known as 5α-androstane-3α,17β-diol and sometimes shortened in the literature to 3α-diol, is an endogenous steroid hormone and neurosteroid and a metabolite of androgens like dihydrotestosterone (DHT).^[1][2][3]

3α-Androstanediol

Names
IUPAC name 5α-Androstane-3α,17β-diol
Systematic IUPAC name (1S,3aS,3bR,5aS,7R,9aS,9bS,11aS)-9a,11a-Dimethylhexadecahydro-1H-cyclopenta[a]phenanthrene-1,7-diol
Other names Hombreol
Identifiers
CAS Number	1852-53-5 Y
3D model (JSmol)	Interactive image
ChEBI	CHEBI:36713
ChemSpider	15039
ECHA InfoCard	100.015.862
PubChem CID	15818
UNII	J34MX0M30Y Y
CompTox Dashboard (EPA)	DTXSID3022378
InChI InChI=1S/C19H32O2/c1-18-9-7-13(20)11-12(18)3-4-14-15-5-6-17(21)19(15,2)10-8-16(14)18/h12-17,20-21H,3-11H2,1-2H3/t12-,13+,14-,15-,16-,17-,18-,19-/m0/s1 Key: CBMYJHIOYJEBSB-KHOSGYARSA-N InChI=1/C19H32O2/c1-18-9-7-13(20)11-12(18)3-4-14-15-5-6-17(21)19(15,2)10-8-16(14)18/h12-17,20-21H,3-11H2,1-2H3/t12-,13+,14-,15-,16-,17-,18-,19-/m0/s1 Key: CBMYJHIOYJEBSB-KHOSGYARBM
SMILES C[C@]12CC[C@H]3[C@@H](CC[C@H]4C[C@H](O)CC[C@@]43C)[C@@H]1CC[C@@H]2O
Properties
Chemical formula	C19H32O2
Molar mass	292.463 g·mol−1
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

Biological activity

3α-Androstanediol is an inhibitory androstane neurosteroid and weak androgen and estrogen.^[1][2][3]

As a neurosteroid, it acts as a potent positive allosteric modulator of the GABA_A receptor,^[4] and has been found to have rewarding,^[5][6] anxiolytic,^[7] pro-sexual,^[8] and anticonvulsant effects.^[9][10] As androgens such as testosterone and DHT are known to have many of the same effects as 3α-diol and are converted into it in vivo, it is thought that this compound may in part be responsible for said effects.^{[5][6][7][10]}

Relative to its isomer 3β-androstanediol, which is a potent estrogen, 3α-androstanediol has substantially lower, though still significant affinity for the estrogen receptors, with a several-fold preference for ERβ over ERα.^[11][12] It has approximately 0.07% and 0.3% of the affinity of estradiol at the ERα and ERβ, respectively.^[13]

Biochemistry

v t e Testosterone metabolism in humans This diagram illustrates the metabolic pathways involved in the metabolism of DHT in humans. In addition to the transformations shown in the diagram, conjugation (e.g., sulfation and glucuronidation) occurs with DHT and metabolites that have one or more available hydroxyl (–OH) groups.

3α-Androstanediol shows high affinity for sex hormone-binding globulin (SHBG), similar to that of testosterone.^[14]

Chemistry

See also: List of neurosteroids

3α-Androstanediol, also known as 5α-androstane-3α,17β-diol, is a naturally occurring androstane steroid and a structural analogue of DHT (5α-androstan-17β-ol-3-one). A notable positional isomer of 3α-androstanediol is 3β-androstanediol.

An orally active synthetic analogue of 3α-androstanediol, 17α-ethynyl-3α-androstanediol (HE-3235, Apoptone), was formerly under investigation for the treatment of prostate cancer and breast cancer.^[15]