title: Conjugate additions to phenylglycinol-derived unsaturated delta-lactams. Enantioselective synthesis of uleine alkaloids.
abstract: The stereochemical outcome of the conjugate addition of a variety of stabilized nucleophiles (2-indoleacetic enolates and sulfur-stabilized anions) to the phenylglycinol-derived unsaturated lactams trans-2, cis-2, and its 8-ethyl-substituted analogue 10 is studied. The factors governing the exo or endo facial stereoselectivity are discussed. This methodology provides short synthetic routes to either cis- or trans-3,4-disubstituted enantiopure piperidines as well as efficient routes for the enantioselective construction of the tetracyclic ring system of uleine alkaloids, both in the normal and 20-epi series. The formal total synthesis of several alkaloids of this group is reported.
authors.affiliation: Laboratory of Organic Chemistry and Department of Physical Chemistry, Faculty of Pharmacy, University of Barcelona, 08028 Barcelona, Spain. amat@ub.edu
authors.forename: Mercedes
authors.initials: M
authors.lastname: Amat
authors.forename: Maria
authors.initials: M
authors.lastname: Pérez
authors.forename: Núria
authors.initials: N
authors.lastname: Llor
authors.forename: Carmen
authors.initials: C
authors.lastname: Escolano
authors.forename: F Javier
authors.initials: FJ
authors.lastname: Luque
authors.forename: Elies
authors.initials: E
authors.lastname: Molins
authors.forename: Joan
authors.initials: J
authors.lastname: Bosch
mesh_terms: D000470:Alkaloids / Q000138:chemical synthesis*; D001952:Bridged-Ring Compounds / Q000138:chemical synthesis*; D018360:Crystallography, X-Ray; D004983:Ethanolamines; D005998:Glycine / Q000031:analogs & derivatives* / Q000737:chemistry*; D007769:Lactams / Q000138:chemical synthesis*; D008968:Molecular Conformation; D013237:Stereoisomerism
chemical_list: D000470:Alkaloids; D001952:Bridged-Ring Compounds; D004983:Ethanolamines; D007769:Lactams; C428545:uleine; C005332:N-phenylethanolamine; D005998:Glycine