Complexes of group IIA cations with adenosine 5'-triphosphate.

The infrared and Raman spectra of the disodium salts of magnesium and calcium with adenosine 5'-triphosphate (ATP) along with the Be2+, Mg2+, Ca2+, Sr2+, and Ba2+ salts with H2ATP2- and Ca2+, Sr2+ and Ba2+ salts with ATP4- in the solid state are reported and the structural implications of these data considered. The infrared and Raman findings for the disodium salts of ATP with calcium and magnesium are in disagreement with earlier conclusions that ATP-4 is acting as a tetradentate ligand. Similarities among the spectra of all substances suggest that the group IIA cations interact mainly with the beta- and gamma-phosphates of ATP, in accordance with studies in aqueous solutions.