The invention provides compounds of Formula (I) that bind to GABA.sub.A
receptors. In the above formula, variables are defined herein. Such
compounds may be used to modulate ligand binding to GABA.sub.A receptors
in vivo or in vitro, and are particularly useful in the treatment of a
variety of central nervous system (CNS) disorders in humans, domesticated
companion animals, and livestock animals. Compounds provided herein may
be administered alone or in combination with one or more other CNS agents
to potentiate the effects of the other CNS agent(s). Pharmaceutical
compositions and methods for treating such disorders are provided, as are
methods for using such ligands for detecting GABA.sub.A receptors (e.g.,
receptor localization studies) ##STR00001##