Posovolone

Posovolone
Clinical data
Other names	CO-134444; Co 134444; V-134444; 3β-Hydroxy-21-(1H-imidazol-1-yl)-3α-(methoxymethyl)-5α-pregnan-20-one
Identifiers
	IUPAC name 1-[(3R,5S,8R,9S,10S,13S,14S,17S)-3-hydroxy-3-(methoxymethyl)-10,13-dimethyl-1,2,4,5,6,7,8,9,11,12,14,15,16,17-tetradecahydrocyclopenta[a]phenanthren-17-yl]-2-imidazol-1-ylethanone;
CAS Number	256955-84-7;
PubChem CID	9802683;
ChemSpider	7978445;
UNII	1GA9JVO9ZA;
Chemical and physical data
Formula	C26H40N2O3
Molar mass	428.617 g·mol−1
3D model (JSmol)	Interactive image;
	SMILES C[C@]12CC[C@@](C[C@@H]1CC[C@@H]3[C@@H]2CC[C@]4([C@H]3CC[C@@H]4C(=O)CN5C=CN=C5)C)(COC)O;
	InChI InChI=1S/C26H40N2O3/c1-24-10-11-26(30,16-31-3)14-18(24)4-5-19-20-6-7-22(25(20,2)9-8-21(19)24)23(29)15-28-13-12-27-17-28/h12-13,17-22,30H,4-11,14-16H2,1-3H3/t18-,19-,20-,21-,22+,24-,25-,26+/m0/s1; Key:BRVGKZNQWCQKTC-MVCIVNJCSA-N;

Posovolone (developmental code name Co 134444) is a synthetic neurosteroid which was under development as a sedative/hypnotic medication for the treatment of insomnia.^[1]^[2]^[3]^[4] It is orally active and acts as a GABA_A receptor positive allosteric modulator.^[1]^[5]^[2] In animals, posovolone shows anticonvulsant, anxiolytic-like, ataxic, and sleep-promoting effects and appeared to produce effects similar to those of pregnanolone.^[2]^[6] Development of the agent was started by 1999 and appears to have been discontinued by 2007.^[1]^[6] In 2021, an INNTooltip International Nonproprietary Name was registered for posovolone with the descriptor of "antidepressant".^[5] Posovolone was originally developed by Purdue Pharma.^[1]