Total synthesis of (5R,6R,8R,9S)-(-)-5,9Z-indolizidine 221T using sulfinimine-derived N-sulfinyl beta-amino ketones.
The first total asymmetric synthesis of the poison frog alkaloid (-)-221T, a 5,6,8-trisubstituted indolizidine is described. The key core piperidine ring was constructed via an acid catalyzed intramolecular cascade Mannich cyclization reaction of a N-sulfinyl syn-alpha-methyl beta-amino ketone and crotonaldehyde. The beta-amino ketone was prepared via the reaction of prochiral lithium Weinreb amide enolate with an enantiopure N-2,4,6-triisopropylphenylsulfinyl imine.
Davis
Franklin A
FA
Department of Chemistry, Temple University, Philadelphia, PA 19122, USA. fdavis@temple.edu
Song
Minsoo
M
Qiu
Hui
H
Chai
Jing
J
D000588:Amines / Q000737:chemistry; D007097:Imines / Q000737:chemistry; D054836:Indolizidines / Q000138:chemical synthesis*; D007659:Ketones / Q000737:chemistry; D013452:Sulfonium Compounds / Q000737:chemistry
D000588:Amines; D007097:Imines; D054836:Indolizidines; D007659:Ketones; D013452:Sulfonium Compounds; C522016:sulfinimine