1 research outputs found
Lead Optimization of 5‑Aryl Benzimidazolone- and Oxindole-Based AMPA Receptor Modulators Selective for TARP γ‑8
Glutamate
mediates fast excitatory neurotransmission via ionotropic
α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA)
receptors. The trafficking and gating properties of AMPA receptors
(AMPARs) can be amplified by transmembrane AMPAR regulatory proteins
(TARPs), which are often expressed in localized brain regions. Herein,
we describe the discovery, lead optimization, and preclinical characterization
of 5-arylbenzimidazolone and oxindole-based negative modulators of
AMPARs associated with TARP γ-8, the primary TARP found in hippocampus.
High-throughput screen lead <b>4</b> was optimized for potency
and brain penetration to provide benzimidazolone <b>3</b>, JNJ-55511118. Replacement of the benzimidazolone core in <b>3</b> with an oxindole mitigated reactive metabolite formation
and led to the identification of <b>18</b> (GluA1/γ-8
pIC<sub>50</sub> = 9.7). Following oral dosing in rats, <b>18</b> demonstrated robust target engagement in hippocampus as assessed
by <i>ex vivo</i> autoradiography (ED<sub>50</sub> = 0.6
mg/kg, plasma EC<sub>50</sub> = 9 ng/mL)