Convergent Strategy Towards the Synthesis of Restricted Analogues of Peloruside A

A rapid convergent strategy to access unsaturated analogues of peloruside A has been demonstrated. This is depicted as an original C11C12 aldol connection between a C12C20 ketone fragment and a C2C11 pyran fragment bearing an aldehyde function, with high yield and a good level of diastereoselectivity. The desired unsaturated macrocycle was obtained by a late-stage ring closing metathesis reaction.