Homoharringtonine and its congener cephalotaxine were synthesized. Oxidative ring-opening of a furan unveils an amine-tethered dicarbonyl, which undergoes spontaneous transannular Mannich cyclization. The cascade builds the full cephalotaxine substructure in a single operation in 60 % yield. A Noyori reduction enabled synthesis of the title compounds with excellent enantioselectivity (k =278).
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