Carbohydrate based IMDA/aldol strategy towards the densely functionalized trans-decalin subunit of azadirachtin

Abstract

L-Rhamnal is converted into an hex-2-en-4-ulo C-glycopyranoside in which properly configured diastereomeric centers, asymmetric as well as geometric, are developed in the pendant anomeric substitutent via a Claisen aldol addition, and the resulting product proceeds via an IMDA reaction to provide a highly functionalised terpene AB ring system.

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