Novel acyclic ligands for metal cations based on the adjacent bistetrahydrofuran as analogs of natural Annonaceous acetogenins

The acrylic ligands with an adjacent bistetrahydrofuran (THF) skeleton have been synthesized as analogs of bullatacin, a representative natural product in a family of Annonaceous acetogenins, and their binding properties towards metal cations have been investigated. The dihydroxyl bis-THF ligands with alkyl chains showed specific binding toward Ca²⁺, and those with acetamido groups exhibited potent binding with Ca²⁺ and Mg²⁺. The ligand with ether chains showed higher affinity toward Mg²⁺. These binding properties which depend on the nature of side chains and their stereochemistry have been analyzed by molecular modeling.