Homoquinolinic acid

Homoquinolinic acid (HQA) is a potent excitotoxin^[1] that is a conformationally restricted analogue of N-methyl-D-aspartate (NMDA) and a partial agonist of the main/glutamate site of the NMDA receptor, with some selectivity for NR2B subunit-containing receptors.^[2][3][4] It is approximately equipotent to NMDA and about five times more potent than quinolinic acid as an agonist of the NMDA receptor.^[5] HQA has also been found to label a novel yet uncharacterized binding site, which can be distinguished from the NMDA receptor with the use of 2-carboxy-3-carboxymethylquinoline (CCMQ), a selective ligand of the uncharacterized site.^[6]

Homoquinolinic acid

Clinical data
Other names	Homoquinolinate
ATC code	None
Identifiers
IUPAC name 3-(Carboxymethyl)-2-pyridinecarboxylic acid
CAS Number	490-75-5
PubChem CID	3080554
ChemSpider	2338312
PDB ligand	QM1 (PDBe, RCSB PDB)
CompTox Dashboard (EPA)	DTXSID70197658
ECHA InfoCard	100.164.902
Chemical and physical data
Formula	C8H7NO4
Molar mass	181.147 g·mol−1
3D model (JSmol)	Interactive image
SMILES c1cc(c(nc1)C(=O)O)CC(=O)O
InChI InChI=1S/C8H7NO4/c10-6(11)4-5-2-1-3-9-7(5)8(12)13/h1-3H,4H2,(H,10,11)(H,12,13) Key:HQPMJFFEXJELOQ-UHFFFAOYSA-N

See also

• Aspartate
• Ibotenic acid
• Tetrazolylglycine