Synthesis of (-)-N-Acetylslaframine by C-1, C-5 Bis-hydroxyalkylation of (S)-2-(N,N-Dibenzylamino)-1,5-pentanediol via Highly Diastereoselective Lithiation of the Dicarbamate

Abstract

(-)-N-Acetylslaframine, a stable form of the indolizidine alkaloid (-)-slaframine, has been synthesised by a new strategy. Applying highly stereoselective lithiation and substitution reactions, C-2, C-3 and C-8 of the bicyclic skeleton were introduced to an l-glutamic acid derived diol dicarbamate.

indolizidines - chiral 2-amino-1-ω-alkanediols - lithiated dicarbamates - diastereoselectivity - (-)-sparteine

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