(S)-CPW 399

(S)-CPW 399 is a potent and selective agonist of AMPA receptor with Ki value of 747 nM [1].

The α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (AMPA receptor) is an ionotropic transmembrane receptor for glutamate and mediates fast synaptic transmission in the central nervous system. AMPA receptors are oligomeric assemblies of four protein subunits, GluR1-4.

(S)-CPW 399 is a potent and selective AMPA receptor agonist. (S)-CPW 399 exhibited affinity with Ki values of 109, 218, 2137 and 1756 nM for GluR1, GluR2, GluR3 and GluR4 receptors, respectively [1]. In mouse cerebellar granule cells, (S)-CPW 399 induced neuronal cell death in a concentration- and time-dependent way with EC50 value of 70 μM and increased intracellular free-calcium levels ([Ca2+]i ) in a concentration-dependent way with EC50 value of 5 μM [2]. In rat cerebellar granule cells, CPW-399 increased the expression of GABAA receptor δ subunit, which relied on NMDA receptor activation [3]. In Sf9 cells expressing iGluR5, (S)-CPW 399 exhibited affinity for iGluR5 with Ki value of 44 nM. In Xenopus læVis Oocytes, (S)-CPW 399 exhibited agonist activity with EC50 values of 24.9, 13.9, 224 and 34.3 μM for iGluR1, iGluR2, iGluR3 and iGluR4 receptors, respectively [4].

References:
[1].  Campiani G, Morelli E, Nacci V, et al. Characterization of the 1H-cyclopentapyrimidine-2,4(1H,3H)-dione derivative (S)-CPW399 as a novel, potent, and subtype-selective AMPA receptor full agonist with partial desensitization properties. J Med Chem, 2001, 44(26): 4501-4504.
[2].  Sinclair C, Reavy H, Grieve A, et al. Inherent desensitisation-preventing properties of a novel, subtype-selective AMPA receptor agonist, (S)-CPW 399, as a possible explanation for its excitotoxic action in cultured cerebellar granule cells. Neurochem Int, 2003, 42(6): 499-510.
[3].  Salonen V, Kallinen S, Lopez-Picon FR, et al. AMPA/kainate receptor-mediated up-regulation of GABAA receptor delta subunit mRNA expression in cultured rat cerebellar granule cells is dependent on NMDA receptor activation. Brain Res, 2006, 1087(1): 33-40.
[4].  Butini S, Pickering DS, Morelli E, et al. 1H-cyclopentapyrimidine-2,4(1H,3H)-dione-related ionotropic glutamate receptors ligands. structure-activity relationships and identification of potent and Selective iGluR5 modulators. J Med Chem, 2008, 51(20): 6614-6618.

Inherent desensitisation-preventing properties of a novel, subtype-selective AMPA receptor agonist, (S)-CPW 399, as a possible explanation for its excitotoxic action in cultured cerebellar granule cells.[Pubmed:12547649]

Neurochem Int. 2003 May;42(6):499-510.

The synthesis and pharmacological characterisation of (S)-CPW 399 as a novel, potent and subtype-selective agonist of the AMPA receptor was recently reported. Studies have been extended to investigate its excitotoxic action in primary cultures of mouse cerebellar granule cells. (S)-CPW 399 induced neuronal cell death in a time- and concentration-dependent manner (EC(50) approximately 70 microM) at 24-h exposure. (S)-CPW-induced neuronal death could be prevented by co-administration with either of the AMPA/kainate selective receptor antagonists 6-cyano-7-nitro-quinoxaline-2,3-dione (CNQX) and 6-nitro-7-sulphamoylbenzo[f]quinoxaline-2,3-dione (NBQX) or by the 2,3-benzodiazepine, GYKI 53655 (a selective AMPA receptor antagonist); while no protection was afforded by either the NMDA receptor antagonist D,L(+/-)-2-amino-5-phosphonopentanoate (APV) or by nifedipine (an L-type calcium channel antagonist) when used alone or in combination. Cyclothiazide, which blocks AMPA receptor desensitisation, caused minimal potentiation of (S)-CPW 399-induced neuronal death, supporting accumulating evidence that (S)-CPW 399 is a full AMPA receptor agonist that markedly prevents a receptor desensitised conformation. (S)-AMPA, (S)-willardiine (a naturally-occurring heterocyclic excitatory amino acid) and its halogenated derivative, (S)-5-fluorowillardiine, had no deleterious effect on neuronal viability when used alone but each, in the presence of cyclothiazide, induced a concentration-dependent excitotoxic cell death with a rank order of potency (fluorowillardiine>>AMPA=willardiine). (S)-CPW 399 stimulated an increase in intracellular free-calcium levels ([Ca(2+)](i)) in a concentration-dependent fashion (EC(50) approximately 5 microM) attaining a value of six-fold that of 'resting' cells at maximum stimulation; achieved at approximately 100 microM (S)-CPW 399. The (S)-CPW 399-stimulated increase in [Ca(2+)](i) was virtually abolished by GYKI 53655, NBQX, CNQX and by cobalt ions; markedly inhibited by nifedipine and marginally affected by D-APV. These results suggest that (S)-CPW 399 may be used as a pharmacological tool to aid in the investigation of the role of AMPA receptors in excitotoxicity and their molecular mechanisms of desensitisation.

1H-cyclopentapyrimidine-2,4(1H,3H)-dione-related ionotropic glutamate receptors ligands. structure-activity relationships and identification of potent and Selective iGluR5 modulators.[Pubmed:18811139]

J Med Chem. 2008 Oct 23;51(20):6614-8.

(S)-CPW399 ((S)-1) is a potent and excitotoxic AMPA receptor partial agonist. Modifying the cyclopentane ring of (S)-1, we developed two of the most potent and selective functional antagonists (5 and 7) for kainate receptor (KA-R) subunit iGluR5. Derivatives 5 and 7, with their unique pharmacological profile, may lead to a better understanding of the different roles and modes of action of iGluR1-5 subunits, paving the way for the synthesis of new potent, subunit selective iGluR5 modulators.

Characterization of the 1H-cyclopentapyrimidine-2,4(1H,3H)-dione derivative (S)-CPW399 as a novel, potent, and subtype-selective AMPA receptor full agonist with partial desensitization properties.[Pubmed:11741469]

J Med Chem. 2001 Dec 20;44(26):4501-4.

(S)-CPW399 (2b) is a novel, potent, and subtype-selective AMPA receptor full agonist that, unlike (S)-willardiine and related compounds, in mouse cerebellar granule cells, stimulated an increase in [Ca(2+)](i), and induced neuronal cell death in a time- and concentration-dependent manner. Compound 2b appears to be a weakly desensitizing, full agonist at AMPA receptors and therefore represents a new pharmacological tool to investigate the role of AMPA receptors in excitotoxicity and their molecular mechanisms of desensitization.