An enantioselective synthesis of the C-35 threo, trans, threo-mono-tetrahydrofuran annonaceous acetogenin longifolicin through use of chiral long-chain alpha- and gamma-OMOM allylic stannanes and (E)-ethyl 3-formyl-2-propenoate as the starting materials is described. The synthesis is structurally definitive and potentially applicable to other members of this family of cytotoxic acetogenins. (C) 1998 Elsevier Science Ltd. All rights reserved.