Studies directed towards the synthesis of antascomicin A: stereoselective synthesis of the C1–C21 fragment of the molecule

A stereoselective synthesis of the C1–C21 fragment of the non-immunosuppressive immunophilin-binding natural product, antascomicin A was achieved using, as key steps, highly stereoselective Aldol reactions to build the C1–C17 fragment and a Nozaki–Hiyama–Kishi reaction to couple it with the remaining C18–C21 moiety.