Polyfunctional Binding of Thymidine 5'-Triphosphate with a Synthetic Polyammonium Receptor Containing Aromatic Groups. Crystal Structure of the Nucleotide-Receptor Adduct

The protonated forms of the new polyfunctional polyamine receptors L, containing two terpyridine units linked together by two diamine spacers, interact with the nucleotide thymidine 5'-triphosphate (TTP) to form stable adducts in aqueous solution. Both solution studies and the crystal structure of the [(H sub(4)L)HTTP] super(.)12H sub(2)O adduct show that tight association of the two partners is achieved by the formation of hydrogen bonds and salt bridges involving the ammonium groups of L and TTP phosphate oxygen atoms and multiple interactions of the nucleobase with aliphatic and aromatic groups of the ligand, mimicking the modes of interaction of TTP binding proteins.