COR 170

A novel CB2 agonist, COR167, potently protects rat brain cortical slices against OGD and reperfusion injury.[Pubmed:23036353]

Pharmacol Res. 2012 Dec;66(6):555-63.

Cannabinoid CB2 receptor activation has been shown to have many pharmacological but not psychotropic effects. The aim of this study was to investigate the potential protection of brain tissues afforded by the novel substituted 4-quinolone-3-carboxylic acid derivative COR167, a selective CB2 agonist, toward ischemia and reperfusion-induced injury, as well as the mechanism of this potential effect. Rat brain cortical slices subjected to oxygen and glucose deprivation (OGD) followed by re-oxygenation were used. Cell damage was quantified by measuring at the end of the reperfusion phase the release into the artificial cerebrospinal fluid (ACSF) of lactate dehydrogenase (LDH), glutamate, IL-6 and TNF-alpha and by evaluating in tissue the lipid-peroxides (thiobarbituric acid-reactive substances, TBARS), the free, reduced glutathione content (GSH) and the water gain (TWG), taken as an index of cell swelling. COR167 (10nM or 100 nM), added to ACSF during the entire reperfusion phase, markedly reduced LDH and glutamate release, as well as TWG. Lower (0.1-1 nM) or higher concentrations (1,000 nM) were ineffective, suggesting thereby an hormetic behavior. COR167 at 10nM concentration markedly reverted in tissues TBARS increase and GSH decrease, while reducing IL-6 and TNF-alpha release into ACSF. COR167 effects on glutamate and LDH release were abrogated by the selective CB2 inverse-agonists COR170 (1 nM) and AM630 (1muM) but not by the CB1 antagonist AM251 (1 muM). COR170 as well as AM630 per se were able to revert TWG. The CB2 receptor agonist COR167 potently protected rat brain cortical slices against OGD and reperfusion injury, partly through CB2 receptors activation.

Investigations on the 4-quinolone-3-carboxylic acid motif. 2. Synthesis and structure-activity relationship of potent and selective cannabinoid-2 receptor agonists endowed with analgesic activity in vivo.[Pubmed:18680276]

J Med Chem. 2008 Aug 28;51(16):5075-84.

Quinolone-3-carboxamides 11 bearing at position 5, 6, 7, or 8 diverse substituents such as halides, alkyl, aryl, alkoxy, and aryloxy groups differing in their steric/electronic properties, were prepared. The new compounds were tested in vitro for CB1 and CB2 receptor affinity in comparison with the reference compounds rimonabant and SR144528. The tested compounds exhibited CB2 affinity in the range from 55.9 to 0.8 nM and CB1 affinity in the range from >10,000 to 5.3 nM, with selectivity indeces [Ki(CB1)/Ki(CB2)] varying from >2666.6 to 1.23. On the basis of the structure-selectivity relationship developed, the presence of a substituent at C6/C8 or C7 well accounts for the high or low CB2 selectivity, respectively. Compound 11c, characterized by high CB2 affinity and selectivity, showed analgesic activity in the formalin test of acute peripheral and inflammatory pain in mice as a result of selective CB2 agonistic activity.