title: Conformation and charge distribution of bicyclic beta-lactams: structure-activity relationships.
abstract: The structures of 7-oxo-1-azabicyclo[3.2.0]heptane and its 4-oxa, 3-ethylene-4-oxa, and 3-ethylene-6-methyl-4-oxa derivatives, and of 8-oxo-1-azabicyclo[4.2.0]octane and its 5-oxa derivative, were studied by ab initio methods. Conformations were refined without constraints using the 4-21G and the 4-21G* basis sets, and energies and charge distributions were improved by single-point 6-31G*/4-21G* calculations. The results are are interpreted in terms of structural trends related to beta-lactamase inhibitor capability.
authors.affiliation: Departamento de Química Física, Facultad de Química, Santiago de Compostela, Spain.
authors.forename: B
authors.initials: B
authors.lastname: Fernández
authors.forename: L
authors.initials: L
authors.lastname: Carballeira
authors.forename: M A
authors.initials: MA
authors.lastname: Ríos
mesh_terms: D013329:Structure-Activity Relationship; D065093:beta-Lactamase Inhibitors; D047090:beta-Lactams / Q000737:chemistry* / Q000494:pharmacology
chemical_list: D065093:beta-Lactamase Inhibitors; D047090:beta-Lactams