title: Cascade cyclization, dipolar cycloaddition to bridged tricyclic amines related to the Daphniphyllum alkaloids.
abstract: A tandem one-pot reaction of an aldehyde with a primary amine involving condensation and then cyclization (N-alkylation), followed by intramolecular dipolar cycloaddition of the resulting nitrone or azomethine ylide, provides a synthesis of bridged tricyclic amines. The reaction was most successful using hydroxylamine, and when the dipolarophile was an unsaturated ester, subsequent reduction of the N-O bond and cyclization to the lactam provided the core ring system of the yuzurimine, daphnilactone B, and bukittinggine type Daphniphyllum alkaloids.
authors.affiliation: Department of Chemistry, University of Sheffield, Brook Hill, Sheffield, S3 7HF, UK. i.coldham@sheffield.ac.uk
authors.forename: Iain
authors.initials: I
authors.lastname: Coldham
authors.forename: Adam J M
authors.initials: AJ
authors.lastname: Burrell
authors.forename: Hélène D S
authors.initials: HD
authors.lastname: Guerrand
authors.forename: Niall
authors.initials: N
authors.lastname: Oram
mesh_terms: D000447:Aldehydes / Q000737:chemistry*; D000470:Alkaloids / Q000138:chemical synthesis* / Q000737:chemistry*; D000588:Amines / Q000737:chemistry*; D018360:Crystallography, X-Ray; D003500:Cyclization; D008968:Molecular Conformation; D015394:Molecular Structure; D031995:Saxifragaceae / Q000737:chemistry*; D000077743:Diterpene Alkaloids
chemical_list: D000447:Aldehydes; D000470:Alkaloids; D000588:Amines; C114746:bukittinggine; D000077743:Diterpene Alkaloids; C512154:daphnilactone B