title: 2D NMR analysis of highly restricted internal rotation in 2-methylthio-3H-4-p-bromophenyl)-7-[(ortho- and para-substituted)-phenylthio]-1, 5-benzodiazepines.
abstract: The complete assignments of twelve 4-aryl-7-thioaryl-1,5-benzodiazepines 1H and 13C spectra, performed with the use of high resolution variable solvent and temperature 1D and 2D techniques (e.g. HOMOCOSY, NOESY, HMQC and HMBC), lead to the determination of conformational equilibria between two rotamers having the aromatic ring of the thioaryl oriented in a perpendicular or helical orientation toward the benzodiazepine ring. The restricted rotation was evaluated from the population of these conformers.
authors.affiliation: Instituto de Química, Universidad Nacional Autonoma de Mexico, UNAM Circuito Exterior, CU Mexico DF.
authors.forename: E
authors.initials: E
authors.lastname: Cortes
authors.forename: M I
authors.initials: MI
authors.lastname: Becerra
authors.forename: Y M
authors.initials: YM
authors.lastname: Osornio
authors.forename: E
authors.initials: E
authors.lastname: Díaz
authors.forename: K
authors.initials: K
authors.lastname: Jankowski
mesh_terms: D001569:Benzodiazepines / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D008968:Molecular Conformation; D012399:Rotation
chemical_list: D001569:Benzodiazepines