CTEP

• CAT Number: I005248
• CAS Number: 871362-31-1
• Molecular Formula: C19H13ClF3N3O
• Molecular Weight: 391.77
• Purity: ≥95%
• Synonyms: 2-chloro-4-[2-[2,5-dimethyl-1-[4-(trifluoromethoxy)phenyl]imidazol-4-yl]ethynyl]pyridine
• InChI: InChI=1S/C19H13ClF3N3O/c1-12-17(8-3-14-9-10-24-18(20)11-14)25-13(2)26(12)15-4-6-16(7-5-15)27-19(21,22)23/h4-7,9-11H,1-2H3
• InChIKey: GOHCTCOGYKAJLZ-UHFFFAOYSA-N
• SMILES: CC1=C(N=C(N1C2=CC=C(C=C2)OC(F)(F)F)C)C#CC3=CC(=NC=C3)Cl

CTEP (RO 4956371) is a novel, long-acting, orally bioavailable allosteric antagonist of mGlu5 receptor with IC50 of 2.2 nM, and shows > 1000-fold selectivity over other mGlu receptors. CTEP is a click chemistry reagent, it contains an Alkyne group and can undergo copper-catalyzed azide-alkyne cycloaddition (CuAAc) with molecules containing Azide groups.
CTEP (RO 4956371) inhibits quisqualate-induced Ca2+ mobilization with an IC50 of 11.4 nM and [3H]IP accumulation with an IC50 of 6.4 nM in HEK293 cells stably expressing human mGlu5. CTEP (RO 4956371) inhibits the constitutive activity of human mGlu5 by approximately 50% with an IC50 of 40.1 nM in HEK293 cells stably expressing human mGlu5[1].
CTEP (RO 4956371) is significantly active at doses of 0.1 mg/kg and 0.3 mg/kg in treatment of anxiety in mouse. CTEP (RO 4956371) significantly increases drinking time at doses of 0.3 mg/kg and 1.0 mg/kg in the Vogel conflict drinking test in rat, whereas it has no effect at lower doses. The half-life of CTEP (RO 4956371) (oral) is 18 h, and the B/P ratio based on total drug concentrations in plasma and whole brain homogenates is 2.6 in mice. After single oral doses of 4.5 and 8.7 mg/kg CTEP (RO 4956371) formulated as microsuspension in a saline/Tween vehicle administrated to adult C57BL/6 mice is rapidly absorbed and achieves close to maximal exposure after approximately 30 min. Chronic administration in adult mice with a dose of 2 mg/kg p.o. every 48 h for 2 months reaches a minimal CTEP (RO 4956371) brain exposure of 240 ng/g. CTEP (RO 4956371) fully displaces [3H]ABP688 in mouse brain regions known to express mGlu5, and 50% displacement is achieved with doses producing an average compound concentration of 77.5 ng/g measured in whole brain homogenate[1]. CTEP (RO 4956371) (2 mg/kg, p.o. bid) achieves uninterrupted mGlu5 occupancy per 48 hours in mice. CTEP (RO 4956371) (2 mg/kg, p.o.) treatment corrects elevated hippocampal long-term depression, excessive protein synthesis, and audiogenic seizures in the Fmr1 knockout mouse[2].

Reference

[1]. Lindemann L, et al. CTEP: a novel, potent, long-acting, and orally bioavailable metabotropic glutamate receptor 5 inhibitor. J Pharmacol Exp Ther. 2011 Nov;339(2):474-86.
 [Content Brief]

[2]. Michalon A, et al. Chronic pharmacological mGlu5 inhibition corrects fragile X in adult mice. Neuron. 2012 Apr 12;74(1):49-56.
 [Content Brief]