title: Use of (S)-trans-gamma-monocyclofarnesol as a useful chiral building block for the stereoselective synthesis of diterpenic natural products.
abstract: A comprehensive study of the exploitation of (S)-trans-gamma-monocyclofarnesol as a useful chiral building block for the stereoselective synthesis of natural diterpene derivatives is here described. The farnesol derivative (+)-1 was used as starting material in the preparation of the diterpenes (S)-dehydroambliol-A and (S)-trixagol, as well as for the syntheses of the dinorditerpene (S)-dinortrixagone and of the guanidine-interrupted terpenoid (S)-dotofide. Key steps of the presented syntheses were the cross-coupling between an allyl acetate and a Grignard reagent, the Wittig reaction, the selective preparation ofa diacylguanidine derivative and the alkylation of a sulfone derivative, followed by the reductive removal of the same functional group. It is worth noting that the natural products (+)-8, (+)-12 and (+)-15 were prepared stereoselectively for the first time, thus allowing the unambiguous assignment of their absolute configuration.
authors.forename: Stefano
authors.initials: S
authors.lastname: Serra
authors.forename: Alessandra A
authors.initials: AA
authors.lastname: Cominetti
authors.forename: Veronica
authors.initials: V
authors.lastname: Lissoni
mesh_terms: D004224:Diterpenes / Q000138:chemical synthesis*; D012717:Sesquiterpenes / Q000737:chemistry*; D013237:Stereoisomerism
chemical_list: C578736:(S)-trans-gamma-monocyclofarnesol; D004224:Diterpenes; D012717:Sesquiterpenes