title: Total synthesis of (+)-cassaine utilizing an anionic polycyclization strategy.
abstract: A stereoselective total synthesis of (+)-cassaine (1) via an anionic polycyclization methodology is described. Commercially available (+)-carvone (5), the only chiral source, was used to fix the entire stereochemistry of the natural product. Anionic polycyclization of a new substituted 2-(methoxycarbonyl)cyclohex-2-en-1-one (4) with known 1-phenylysulfinyl-3-penten-2-one (3) provided the versatile tricycle (2) with requisite stereochemistry. A sequence of functional group manipulations of tricycle (2) furnished the natural product 1.
authors.affiliation: Département de Chimie, Faculté des Sciences et de Génie, Pavillon Alexandre-Vachon, Université Laval , 1045, avenue de la Médecine, Québec City, QC G1V 0A6, Canada , and Département de Chimie, Université de Sherbrooke , Sherbrooke, QC, J1K 2R1 Canada.
authors.forename: Kontham
authors.initials: K
authors.lastname: Ravindar
authors.forename: Pierre-Yves
authors.initials: PY
authors.lastname: Caron
authors.forename: Pierre
authors.initials: P
authors.lastname: Deslongchamps
mesh_terms: D045784:Abietanes; D000470:Alkaloids / Q000138:chemical synthesis* / Q000737:chemistry; D000838:Anions / Q000138:chemical synthesis / Q000737:chemistry; D003500:Cyclization; D008968:Molecular Conformation; D013237:Stereoisomerism
chemical_list: D045784:Abietanes; D000470:Alkaloids; D000838:Anions; C010696:cassaine