First highly stereocontrolled synthesis of the unusual 1-hydroxy endo,endo-2,6-diaryl-3,7-dioxabicyclo[3.3.0]octane lignan skeleton

This Letter describes a highly diastereoselective synthesis of the unique 1-hydroxy endo,endo-2,6-diaryl-3,7-dioxabicyclo[3.3.0]octane skeleton starting from a stereodefined 4-arylidenetetrahydrofuran obtained by a multicomponent reaction. The key step of this synthesis is a dealkylative cyclization reaction performed on the corresponding epoxide, generating four contiguous stereogenic centers with total stereocontrol.