0000000000924118
AUTHOR
Gabriele Quandt
Stereoselektive Synthese enantiomerenreiner Nupharamin-Alkaloide aus dem Castoreum (Bibergeil)
Tierische Parfumalkaloide: Eine stereoselektive Mannich-Michael-Reaktion an N-Galactosylfurylaldimin zu 1 (Piv = Pivaloyl), anschliesende konjugierte Cuprataddition und stereoselektive Protonierung des gebildeten Enolats, alle kontrolliert vom Kohlenhydrat, ermoglichen erstmals die Totalsynthese des all-cis-Nupharamins 2 aus dem Castoreum. Enolatprotonierung nach Abspaltung des Kohlenhydrats fuhrt alternativ zum Epimer 3.
Stereoselective Synthesis of Enantiomerically Pure Nupharamine Alkaloids from Castoreum
An animalic note: The first total synthesis of the all-cis nupharamine 2, an alkaloid from beaver castoreum, is based on the stereoselective domino Mannich-Michael reaction of N-galactosylfurylaldimine to give 1 (Piv = pivaloyl), subsequent conjugate cuprate addition, and stereoselective protonation of the enolate. These reactions are all controlled by the carbohydrate. Protonation of the enolate after cleavage of the auxiliary leads to epimer 3.