title: Total syntheses of mitragynine, paynantheine and speciogynine via an enantioselective thiourea-catalysed Pictet-Spengler reaction.
abstract: The pharmacologically interesting indole alkaloids (-)-mitragynine, (+)-paynantheine and (+)-speciogynine were synthesised in nine steps from 4-methoxytryptamine by a route featuring (i) an enantioselective thiourea-catalysed Pictet-Spengler reaction, providing the tetrahydro-β-carboline ring and (ii) a Pd-catalysed Tsuji-Trost allylic alkylation, closing the D-ring.
authors.affiliation: Van 't Hoff Institute for Molecular Sciences, Science Park 904, 1098XH Amsterdam, The Netherlands.
authors.forename: Isabel P
authors.initials: IP
authors.lastname: Kerschgens
authors.forename: Elise
authors.initials: E
authors.lastname: Claveau
authors.forename: Martin J
authors.initials: MJ
authors.lastname: Wanner
authors.forename: Steen
authors.initials: S
authors.lastname: Ingemann
authors.forename: Jan H
authors.initials: JH
authors.lastname: van Maarseveen
authors.forename: Henk
authors.initials: H
authors.lastname: Hiemstra
mesh_terms: D002384:Catalysis; D060326:Chemistry Techniques, Synthetic; D026121:Indole Alkaloids / Q000138:chemical synthesis* / Q000737:chemistry; D000078183:Oxindoles; D046948:Secologanin Tryptamine Alkaloids / Q000138:chemical synthesis* / Q000737:chemistry; D013890:Thiourea / Q000737:chemistry*
chemical_list: D026121:Indole Alkaloids; D000078183:Oxindoles; D046948:Secologanin Tryptamine Alkaloids; C580857:paynantheine; C580856:speciogynine; C001801:mitragynine; D013890:Thiourea