Synthesis, pharmacological and structural characterization, and thermodynamic aspects of GluA2-positive allosteric modulators with a 3,4-dihydro-2H-1,2,4-benzothiadiazine 1,1-dioxide scaffold.Nrholm, A.B., Francotte, P., Olsen, L., Krintel, C., Frydenvang, K., Goffin, E., Challal, S., Danober, L., Botez-Pop, I., Lestage, P., Pirotte, B., Kastrup, J.S.
(2013) J.Med.Chem. 56: 8736-8745
- PubMed: 24131202
- DOI: 10.1021/jm4012092
- Also Cited By: 4U4S, 5ELV, 5OEW, 5BUU, 4U4X
- PubMed Abstract:
Positive allosteric modulators of ionotropic glutamate receptors are potential compounds for treatment of cognitive disorders, e.g., Alzheimer's disease. The modulators bind within the dimer interface of the ligand-binding domain (LBD) and stabilize ...
Positive allosteric modulators of ionotropic glutamate receptors are potential compounds for treatment of cognitive disorders, e.g., Alzheimer's disease. The modulators bind within the dimer interface of the ligand-binding domain (LBD) and stabilize the agonist-bound conformation, thereby slowing receptor desensitization and/or deactivation. Here we describe the synthesis and pharmacological testing at GluA2 of a new generation of 3,4-dihydro-2H-1,2,4-benzothiadiazine 1,1-dioxides. The most potent modulator 3 in complex with GluA2-LBD-L483Y-N754S was subjected to structural analysis by X-ray crystallography, and the thermodynamics of binding was studied by isothermal titration calorimetry. Compound 3 binds to GluA2-LBD-L483Y-N754S with a Kd of 0.35 μM (ΔH = -7.5 kcal/mol and -TΔS = -1.3 kcal/mol). This is the first time that submicromolar binding affinity has been achieved for this type of positive allosteric modulator. The major structural factor increasing the binding affinity of 3 seems to be interactions between the cyclopropyl group of 3 and the backbone of Phe495 and Met496.
Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen , Universitetsparken 2, DK-2100 Copenhagen, Denmark.