title: A diastereoselective total synthesis of trans-trikentrin A: a ring contraction approach.
abstract: A new route to obtain the polyalkylated indole (+/-)-trans-trikentrin A was developed. The synthesis of this natural alkaloid features a thallium(III)-mediated ring contraction reaction to obtain the trans-1,3-disubstituted five-membered ring in a diastereoselective manner. Thallium(III) is chemoselective in this rearrangement, reacting with the olefin without oxidation of the indole moiety. Other key transformations are the Bartoli's reaction to construct the heterocyclic ring and a Heck coupling to add the carbons atom that will originate the nonaromatic cycle.
authors.affiliation: Instituto de Química, Universidade de São Paulo, Av. Prof. Lineu Prestes, 748, CP 26077, CEP 05513-970 São Paulo SP, Brazil. luizfsjr@iq.usp.br
authors.forename: Luiz F
authors.initials: LF
authors.lastname: Silva
authors.forename: Marcus V
authors.initials: MV
authors.lastname: Craveiro
mesh_terms: D001554:Benzene / Q000737:chemistry; D026121:Indole Alkaloids / Q000138:chemical synthesis* / Q000737:chemistry*; D013237:Stereoisomerism; D013379:Substrate Specificity
chemical_list: D026121:Indole Alkaloids; C519345:trikentrin A; D001554:Benzene