Discovery and structure-activity relationship of 1,3-cyclohexyl amide derivatives as novel mGluR5 negative allosteric modulators.

A novel series of trans-1,3-cyclohexyl diamides was discovered and characterized as mGluR5 negative allosteric modulators (NAMs) lacking an alkyne moiety. Conformational constraint of one of the amide bonds in the diamide template led to a spirooxazoline template. A representative compound (24d) showed good in vitro potency, high CNS penetration and, upon subcutaneous dosing, demonstrated efficacy in the mouse marble burying test, generally used as indicative of potential anxiolytic activity.

Pharmacological characterization and modeling of the binding sites of novel 1,3-bis(pyridinylethynyl)benzenes as metabotropic glutamate receptor 5-selective negative allosteric modulators.

Metabotropic glutamate receptor subtype 5 (mGluR5) is a potential drug target in neurological and psychiatric disorders, and subtype-selective allosteric modulators have attracted much attention as potential drug candidates. In this study, the binding sites of three novel 2-methyl-6-(phenylethynyl)pyridine (MPEP)-derived negative allosteric modulators, 2-, 3-, and 4-BisPEB, have been characterized. 2-, 3-, and 4-BisPEB are 1,3-bis(pyridinylethynyl)-benzenes and differ only by the position of the nitrogen atoms in the pyridine rings.

Synergy between L-DOPA and a novel positive allosteric modulator of metabotropic glutamate receptor 4: implications for Parkinson's disease treatment and dyskinesia.

Group III metabotropic glutamate (mGlu) receptors are localized in presynaptic terminals within basal ganglia (BG) circuitry that become hyperactive due to dopamine depletion in Parkinson's disease (PD). For this reason, group III mGlu receptors, in particular mGlu4, have been considered as key strategic targets for non-dopaminergic pharmacological treatments aimed at modulating these synapses, without producing the well known side-effects of l-DOPA, in particular the highly disabling l-DOPA-induced dyskinesia (LID). Herein we add physiological and functional support to this hypothesis using Lu AF21934, a novel selective and brain-penetrant mGlu4 receptor positive allosteric modulator (PAM) tool compound.

4-(1-Phenyl-1H-pyrazol-4-yl)quinolines as novel, selective and brain penetrant metabotropic glutamate receptor 4 positive allosteric modulators.

4-(1-Phenyl-1H-pyrazol-4-yl)quinoline (1) was identified by screening the Lundbeck compound collection, and characterized as having mGlu4 receptor positive allosteric modulator properties. Compound 1 is selective over other mGlu receptors and a panel of GPCRs, ion channels and enzymes, but has suboptimal lipophilicity and high plasma and brain non-specific binding. In view of the challenges at the hit-to-lead stage previously reported in the development of mGlu4 receptor positive allosteric modulators (PAMs), a thorough structure-mGlu4 PAM activity relationship study was conducted to interrogate the chemical tractability of this chemotype.

Structure-activity relationships for negative allosteric mGluR5 modulators.

A series of compounds based on the mGluR5-selective ligand 2-methyl-6-(phenylethynyl)pyridine (MPEP) were designed and synthesized. The compounds were found to be either structural analogues of MPEP, substituted monomers, or dimeric analogues. All compounds retained mGluR5 selectivity with only weak or no activity at other mGluRs or iGluRs.

5-(2'-Pyridyl)-2-aminothiazoles: alkyl amino sulfonamides and sulfamides as potent NPY(5) antagonists.

Synthesis, SAR and physico-chemical properties of an alkyl aminothiazole series 8 and 16 are described. 2-Pyridylaminothiazole based compounds such as 8c and 16a exhibit high affinity at the NPY(5) receptor with desirable cLogPs and solubilities. However, they also suffer from high in vitro and in vivo clearance.

6-Aryl-3-pyrrolidinylpyridines as mGlu5 receptor negative allosteric modulators.

A series of 6-aryl-3-pyrrolidinylpyridine analogs was explored as structurally novel negative allosteric modulators of the mGlu5 receptor lacking an alkyne or oxadiazole moiety. Compounds in this series were characterized by tractable SAR, good in vitro potencies and brain penetration in rodents.