title: Molecular structure and stereoelectronic properties of sarmazenil--a weak inverse agonist at the omega modulatory sites (benzodiazepine receptors): comparison with bretazenil and flumazenil.
abstract: X-ray diffraction and ab initio MO theoretical calculations were used in order to investigate the structural and electronic properties of sarmazenil, a weak inverse agonist at the omega modulatory sites (benzodiazepine receptors). This compound was compared to bretazenil, a partial agonist, and to the antagonist flumazenil on the basis of structural and electronic data. The conformational and theoretical properties (interatomic pi overlap populations, molecular electrostatic potential (MEP), the topology of frontier orbitals, and proton affinity) of these three imidazobenzodiazepinones were determined in order to analyse the stereoelectronic properties in relation with their distinct intrinsic efficacies at the omega modulatory sites.
authors.affiliation: Laboratoire de Chimie Moléculaire Structurale, Facultés Universitaires Notre-Dame de la Paix, Namur, Belgium.
authors.forename: B
authors.initials: B
authors.lastname: López-Romero
authors.forename: G
authors.initials: G
authors.lastname: Evrard
authors.forename: F
authors.initials: F
authors.lastname: Durant
authors.forename: M
authors.initials: M
authors.lastname: Sevrin
authors.forename: P
authors.initials: P
authors.lastname: George
mesh_terms: D001569:Benzodiazepines / Q000737:chemistry* / Q000378:metabolism; D001570:Benzodiazepinones / Q000737:chemistry* / Q000378:metabolism; D001665:Binding Sites; D018360:Crystallography, X-Ray; D005442:Flumazenil / Q000737:chemistry* / Q000378:metabolism; D058785:GABA-A Receptor Agonists; D058787:GABA-A Receptor Antagonists; D007093:Imidazoles / Q000737:chemistry* / Q000378:metabolism; D008958:Models, Molecular; D008968:Molecular Conformation; D015394:Molecular Structure
chemical_list: D001570:Benzodiazepinones; D058785:GABA-A Receptor Agonists; D058787:GABA-A Receptor Antagonists; D007093:Imidazoles; D001569:Benzodiazepines; D005442:Flumazenil; C102747:sarmazenil; C054626:bretazenil