[Kynurenines and drug research].

Currently kynurenines are considered a hot topic, because of their involvement in numerous physiological and pathological processes. The essential amino acid, tryptophan's main metabolism is through the kynurenine pathway. During the degradation of tryptophan, kynurenic acid is formed with the help of kynurenine aminotransferases. Kynurenic acid is an excitatory receptor ligand and it possesses neuroprotective properties. Abnormal decrease or increase in the kynurenic acid level can cause an imbalance in the neurotransmitter systems and it is associated with several neurodegenerative and neuropsychiatric disorders. Kynurenic acid has a poor penetration through the blood-brain barrier, so it is unfit for therapeutic purposes. For this reason, the aim of our research was the synthesis and pharmacological testing of kynurenic acid analogues with a better blood-brain barrier penetration. The newly synthetized kynurenic acid analogues proved to be effective in models of some nervous system disorders (migraine, Huntington's disease). According to our results with the novel kynurenic acid analogues, these molecules may represent a new therapeutic target in the treatment of neurodegenerative diseases. Several patent applications were filed based on our results. Orv Hetil. 2020; 161(12): 443-451.