De Novo Asymmetric Synthesis of d- and l-Swainsonine
摘要:
The enantioselective syntheses of both enantiomers of the indolizidine natural product swainsonine have been achieved in 13 steps from furan. The indolizidine ring system is installed by a one-pot hydrogenolysis of both an azide and an O-Bn group along with an intramolecular reductive amination reaction. The asymmetry of swainsonine was introduced by Noyori reduction of an acylfuran. This route relies upon an Achmatowicz rearrangement, a diastereoselective palladium-catalyzed glycosylation, Luche reduction, and a dihydroxylation reaction.
Decarbonylation of α-tertiary amino acids application to the synthesis of polyhydroxylated indolizidines from D,L-pipecolic acid
作者:María J. Martín-López、Rosa Rodriguez、Francisco Bermejo
DOI:10.1016/s0040-4020(98)00689-9
日期:1998.9
The decarbonylation of the bicyclic α-tertiary carboxamido acid 11 led to the enamide 12, easily transformed into the indolizidine alkaloid 8,8a-trans-8-hydroxy-indolizidine 14. Likewise, the same process applied to the α-substituted pipecolic acid derivative 5 led to the unsaturated ester 6 which was easily transformed either into δ-coniceine 9 or to 14. The thermal fragmentation of the acyl derivative
Decarbonylation of α-tertiary amino acids. Application to the synthesis of polyhydroxylated indolizidines
作者:Rosa Rodríguez、Francisco Bermejo
DOI:10.1016/0040-4039(96)01130-6
日期:1996.7
The decarbonylation of the bicyclic α-tertiaryaminoacid 16 easily obtained from D,L-pipecolic acid, is the key step in our strategy to prepare polyhydroxylatedindolizidines. Thermal fragmentation of the acyl chloride 17 allowed us access to the enamide 19, which has been described as a valuable intermediate in the synthesis of (±)-swainsonine.
De Novo Asymmetric Synthesis of <scp>d</scp>- and <scp>l</scp>-Swainsonine
作者:Haibing Guo、George A. O'Doherty
DOI:10.1021/ol0602811
日期:2006.4.1
The enantioselective syntheses of both enantiomers of the indolizidine natural product swainsonine have been achieved in 13 steps from furan. The indolizidine ring system is installed by a one-pot hydrogenolysis of both an azide and an O-Bn group along with an intramolecular reductive amination reaction. The asymmetry of swainsonine was introduced by Noyori reduction of an acylfuran. This route relies upon an Achmatowicz rearrangement, a diastereoselective palladium-catalyzed glycosylation, Luche reduction, and a dihydroxylation reaction.
De novo asymmetric syntheses of d-, l- and 8-epi-d-swainsonine
作者:Haibing Guo、George A. O'Doherty
DOI:10.1016/j.tet.2007.10.109
日期:2008.1
A highly enantioselective and stereocontrolled approach to d-, l- and 8-epi-d-swainsonine has been developed from achiral furan and γ-butyrolactone. A one-pot hydrogenolysis of both azide and benzyl ether followed by an intramolecular reductive amination has been employed as key step to establish the indolizidine ring system. The absolute stereochemistry was installed by the Noyori reduction and the