K3375 Sigma-Aldrich

Kynurenic acid


Synonym: 4-Hydroxyquinoline-2-carboxylic acid

  • CAS Number 492-27-3

  • Empirical Formula (Hill Notation) C10H7NO3

  • Molecular Weight 189.17

  •  Beilstein/REAXYS Number 147451

  •  EC Number 207-751-5

  •  MDL number MFCD00006753

  •  PubChem Substance ID 24277986

  •  NACRES NA.77



Related Categories AMPA/Kainate Antagonists, Bioactive Small Molecule Alphabetical Index, Bioactive Small Molecules, Cell Biology, Cell Signaling and Neuroscience,
Quality Level   200
assay   ≥98%
mp   275 °C (dec.) (lit.)
SMILES string   OC(=O)c1cc(O)c2ccccc2n1
InChI   1S/C10H7NO3/c12-9-5-8(10(13)14)11-7-4-2-1-3-6(7)9/h1-5H,(H,11,12)(H,13,14)
Gene Information   human ... CHRNA1(1134), CHRNA10(57053), CHRNA2(1135), CHRNA3(1136), CHRNA4(1137), CHRNA5(1138), CHRNA6(8973), CHRNA7(1139), CHRNA9(55584), CHRNB1(1140), CHRNB2(1141), CHRNB3(1142), CHRNB4(1143), GRIA3(2892), GRIA4(2893), GRIK1(2897), GRIK2(2898), GRIK3(2899), GRIK4(2900), GRIK5(2901), GUCA2A(2980), GUCA2B(2981), NGFR(4804), SLC23A2(9962)
rat ... Gria1(50592), Grik1(29559), Grin2a(24409)



Kynurenic acid has been used as a constituent in dissection saline solution for embryonic cerebral cortical cells and human primary astrocytes. It has also been used as a medium supplement for murine intestinal epithelial cell line, MODE-K and induced pluripotent stem cell (iPSC)-derived neurons cells.


1, 5 g in poly bottle

250 mg in poly bottle

Biochem/physiol Actions

Kynurenic acid (KynA) is a non-selective antagonist of N-methyl-d-aspartate (NMDA), α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) and kainate receptors. It blocks kainic acid neurotoxicity. Kynurenic acid also blocks nicotinic acetylcholine receptors. It is a by-product of tryptophan catabolic pathway. Kynurenic acid is a neuromodulator and controls the levels of glutamate, dopamine, acetylcholine and α-aminobutyric acid (GABA). KynA controls neuroendocrine functions and altered levels of KynA is a potential marker in depression, schizophrenia Alzheimer′s and Huntington′s diseases. Normal levels of KynA in the brain is crucial for the cognitive function.

Features and Benefits

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Legal Information

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Safety & Documentation

Safety Information

Personal Protective Equipment 
NONH for all modes of transport
WGK Germany 
Flash Point(F) 
Not applicable
Flash Point(C) 
Not applicable


Certificate of Analysis (COA)

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Certificate of Origin (COO)

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Protocols & Articles


Discover Bioactive Small Molecules for Neuroscience

The nervous system, comprised of the brain and spinal cord (central nervous system, or CNS) and network of nerves that connects the CNS to the rest of the body (peripheral nervous system, or PNS) is ...
Keywords: Bioactive small molecules, Central Nervous System, Diseases, Metabolism, Neurodegenerative Diseases, Neuroscience, Neurotransmission, Neurotransmitters

MSMLS Online Plate Map

Metabolite descriptors included with the software download upon purchase of the product include: Name, Parent CID, molecular formula, molecular weight, CAS, ChEBI, HMDB ID, PubChem Compound and Subst...
Keywords: Mass spectrometry, Metabolites

OAMLS Online Plate Map

OAMLS compounds are conveniently provided at 5µg per well, enough for multiple injections. These are high purity (>95%) compounds supplied in an economical, ready to use format. Compounds are arrange...
Keywords: Metabolites

Peer-Reviewed Papers


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