title: N-Benzyltetrahydropyrido-anellated thiophene derivatives: new anticholinesterases.
abstract: The title compounds, tert-butyl 6-benzyl-2-(3,3-diethylureido)-4,5,6,7-tetrahydrothieno[2,3-c]pyridine-3-carboxylate, C(24)H(33)N(3)O(3)S, (I), 7-benzyl-2-diethylamino-5,6,7,8-tetrahydro-3-oxa-9-thia-1,7-diazafluoren-4-one, C(20)H(23)N(3)O(2)S, (II), and N-(7-benzyl-4-oxo-5,6,7,8-tetrahydro-4H-3,9-dithia-1,7-diazafluoren-2-yl)benzamide, C(23)H(19)N(3)O(2)S(2), (III), form monoclinic crystal systems. In (I) and (II), the molecules are linked into a three-dimensional framework by weak intermolecular C-H...O=C hydrogen bonds, whereas in (III) stronger intermolecular N-H...O=C interactions are observed. The conformation of (I) is further stabilized by an intramolecular N-H...O=C hydrogen bond, which effects the planarity of the ureidothiophenecarboxylate moiety.
authors.affiliation: Pharmaceutical Institute, University of Bonn, An der Immenburg 4, D-53121 Bonn, Germany.
authors.forename: Markus
authors.initials: M
authors.lastname: Pietsch
authors.forename: Martin
authors.initials: M
authors.lastname: Nieger
authors.forename: Michael
authors.initials: M
authors.lastname: Gütschow
mesh_terms: D002800:Cholinesterase Inhibitors / Q000737:chemistry*; D018360:Crystallography, X-Ray; D006575:Heterocyclic Compounds, 3-Ring / Q000737:chemistry*; D008958:Models, Molecular; D013876:Thiophenes / Q000737:chemistry*
chemical_list: D002800:Cholinesterase Inhibitors; D006575:Heterocyclic Compounds, 3-Ring; D013876:Thiophenes