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Discovery of a Series of 2-Phenyl-N-(2-(pyrrolidin-1-yl)phenyl)acetamides as Novel Molecular Switches that Modulate Modes of K(v)7.2 (KCNQ2) Channel Pharmacology: Identification of (S)-2-Phenyl-N-(2-(pyrrolidin-1-yl)phenyl)butanamide (ML252) as a Potent, Brain Penetrant K(v)7.2 Channel Inhibitor

Department of Pharmacology, Vanderbilt University Medical Center , Nashville, Tennessee 37232, United States.
Journal of Medicinal Chemistry (Impact Factor: 5.48). 07/2012; 55(15):6975-9. DOI: 10.1021/jm300700v
Source: PubMed

ABSTRACT A potent and selective inhibitor of KCNQ2, (S)-5 (ML252, IC(50) = 69 nM), was discovered after a high-throughput screen of the MLPCN library was performed. SAR studies revealed a small structural change (ethyl group to hydrogen) caused a functional shift from antagonist to agonist activity (37, EC(50) = 170 nM), suggesting an interaction at a critical site for controlling gating of KCNQ2 channels.

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