title: Synthetic studies toward the kempane diterpenes. Construction of a key tricyclic intermediate.
abstract: A synthetic sequence is described for construction of the tricyclic portion (35) of kempane diterpenes. The central stereochemistry was established by a Diels-Alder addition of 2,6-dimethyl-para-benzoquinone to a 5-membered, dithiane-protected diene, and the addition of acetylide, with very high chemoselectivity, provided a suitably functionalized handle that will be incorporated into the final seven-membered ring. The remaining stereogenic centres about the decalin moiety were established by a series of equilibration and reduction steps.
authors.affiliation: Department of Chemistry, Memorial University of Newfoundland, St. John's, Newfoundland and Labrador, Canada A1B 3X7.
authors.forename: Guanglin
authors.initials: G
authors.lastname: Bao
authors.forename: Liang
authors.initials: L
authors.lastname: Zhao
authors.forename: D Jean
authors.initials: DJ
authors.lastname: Burnell
mesh_terms: D000466:Alkadienes / Q000737:chemistry; D000818:Animals; D016227:Benzoquinones / Q000737:chemistry; D004224:Diterpenes / Q000138:chemical synthesis*; D006575:Heterocyclic Compounds, 3-Ring / Q000138:chemical synthesis*; D020049:Isoptera / Q000737:chemistry* / Q000378:metabolism; D008968:Molecular Conformation; D015394:Molecular Structure; D009281:Naphthalenes / Q000737:chemistry; D013237:Stereoisomerism
chemical_list: D000466:Alkadienes; D016227:Benzoquinones; D004224:Diterpenes; D006575:Heterocyclic Compounds, 3-Ring; D009281:Naphthalenes; C007229:decalin