Hydroxynorketamine

Hydroxynorketamine
	The four possible stereoisomers of Hydroxynorketamine
Clinical data
Other names	HNK; 6-Hydroxynorketamine; 6-HNK
ATC code	None;
Identifiers
	IUPAC name 2-Amino-2-(2-chlorophenyl)-6-hydroxycyclohexan-1-one;
CAS Number	81395-70-2 ;
PubChem CID	133669;
ChemSpider	117907;
UNII	6VAD9SC8NW;
CompTox Dashboard (EPA)	DTXSID701001963 ;
Chemical and physical data
Formula	C12H14ClNO2
Molar mass	239.70 g·mol−1
3D model (JSmol)	Interactive image;
	SMILES C1CC(C(=O)C(C1)(C2=CC=CC=C2Cl)N)O;
	InChI InChI=1S/C12H14ClNO2/c13-9-5-2-1-4-8(9)12(14)7-3-6-10(15)11(12)16/h1-2,4-5,10,15H,3,6-7,14H2; Key:CFBVGSWSOJBYGC-UHFFFAOYSA-N;

Hydroxynorketamine (HNK), or 6-hydroxynorketamine, is a minor metabolite of the anesthetic, dissociative, and antidepressant drug ketamine. It is formed by hydroxylation of the intermediate norketamine, another metabolite of ketamine. As of late 2019, (2R,6R)-HNK is in clinical trials for the treatment of depression.

The major metabolite of ketamine is norketamine (80%). Norketamine is secondarily converted into 4-, 5-, and 6-hydroxynorketamines (15%), mainly HNK (6-hydroxynorketamine). Ketamine is also transformed into hydroxyketamine (5%). As such, bioactivated HNK comprises less than 15% of a dose of ketamine.