Pyridine bioisosteres of potent GluN2B subunit containing NMDA receptor antagonists with benzo[7]annulene scaffold

European Journal of Medicinal Chemistry
2018.0

Abstract

It has been reported that benzo [7]annulen-7-amines bearing electron withdrawing substituents such as 3d with a 2-Cl or 3e with a 2-NO2 moiety show very high affinity towards the ifenprodil binding site of GluN2B subunit containing NMDA receptors. Therefore, bioisosteres of 3 with an electron deficient pyridine ring instead of the chloro- or nitrobenzene ring were envisaged. Starting from pyridine-2,3-dicarboxylic acid (5) a five-step synthesis of the key intermediate, the ketone 10, was developed. Reductive amination with various primary amines and NaBH(OAc)3 led to the homologous secondary amines 11a-c. Subsequent methylation yielded the tertiary amines 12b and 12c. Receptor binding studies with [3H]ifenprodil revealed Ki-values above 100 nM for the most active phenylpropyl- and phenylbutylamines 11b and 11c. The >100-fold reduced GluN2B affinity of pyridines 11b and 11c compared to the GluN2B affinity of the corresponding chloro- and nitrobenzene derivatives 3d and 3e indicates that the pyridine ring is not tolerated as bioisosteric replacement of the chloro- or nitrobenzene ring in this type of compounds.

Knowledge Graph

Similar Paper

Pyridine bioisosteres of potent GluN2B subunit containing NMDA receptor antagonists with benzo[7]annulene scaffold
European Journal of Medicinal Chemistry 2018.0
Synthesis, GluN2B affinity and selectivity of benzo[7]annulen-7-amines
Bioorganic & Medicinal Chemistry 2014.0
Synthesis and receptor binding of thiophene bioisosteres of potent GluN2B ligands with a benzo[7]annulene-scaffold
MedChemComm 2019.0
Thiophene bioisosteres of GluN2B selective NMDA receptor antagonists: Synthesis and pharmacological evaluation of [7]annuleno[b]thiophen-6-amines
Bioorganic & Medicinal Chemistry 2020.0
Hydroxymethyl bioisosteres of phenolic GluN2B-selective NMDA receptor antagonists: Design, synthesis and pharmacological evaluation
European Journal of Medicinal Chemistry 2018.0
Impact of hydroxy moieties at the benzo[7]annulene ring system of GluN2B ligands: Design, synthesis and biological evaluation
Bioorganic & Medicinal Chemistry 2019.0
Negative allosteric modulators of the GluN2B NMDA receptor with phenylethylamine structure embedded in ring-expanded and ring-contracted scaffolds
European Journal of Medicinal Chemistry 2020.0
Do GluN2B subunit containing NMDA receptors tolerate a fluorine atom in the phenylalkyl side chain?
MedChemComm 2017.0
Biososteric Replacement in the Design and Synthesis of Ligands for Nicotinic Acetylcholine Receptors
Medicinal Chemistry Research 2005.0
2-Methyltetrahydro-3-benzazepin-1-ols – The missing link in SAR of GluN2B selective NMDA receptor antagonists
Bioorganic & Medicinal Chemistry 2018.0