title: Brønsted acid-catalyzed highly stereoselective arene-ynamide cyclizations. A novel keteniminium Pictet-Spengler cyclization in total syntheses of (+/-)-desbromoarborescidines A and C.
abstract: [reaction: see text] A Brønsted acid-catalyzed highly stereoselective arene-ynamide cyclization is described. These reactions constitute a keteniminium variant of Pictet-Spengler cyclizations, leading to efficient synthesis of nitrogen heterocycles and related alkaloids. Total syntheses of desbromoarborescidines A and C are illustrated here as first applications of this methodology.
authors.affiliation: Department of Chemistry, University of Minnesota, Minneapolis, Minnesota 55455, USA.
authors.forename: Yanshi
authors.initials: Y
authors.lastname: Zhang
authors.forename: Richard P
authors.initials: RP
authors.lastname: Hsung
authors.forename: Xuejun
authors.initials: X
authors.lastname: Zhang
authors.forename: Jian
authors.initials: J
authors.lastname: Huang
authors.forename: Brian W
authors.initials: BW
authors.lastname: Slafer
authors.forename: Allison
authors.initials: A
authors.lastname: Davis
mesh_terms: D002384:Catalysis; D003500:Cyclization; D026121:Indole Alkaloids / Q000138:chemical synthesis*; D015394:Molecular Structure; D013237:Stereoisomerism
chemical_list: D026121:Indole Alkaloids; C506148:desbromoarborescidine A; C506149:desbromoarborescidine C