Cyclopentane compound

Abstract

The present invention addresses the problem of providing a novel compound that has an OX2R agonist activity. The present invention pertains to a cyclopentane compound represented by formula (I) or a pharmacologically acceptable salt thereof. This compound, or a pharmacologically acceptable salt thereof, has an agonist activity against OX2R, and is useful as a treatment agent, etc., for sleep disorders involving OX2R (e.g., narcolepsy, idiopathic hypersomnia, Kleine-Levin syndrome, hypersomnia associated with a physical disease, hypersomnia associated with a mental disease, hypersomnia associated with a drug or a substance, circadian rhythm sleep-wake disorder, insufficient sleep syndrome, and extended sleep).