Spectral, thermoanalytical and XRD study of zinc(II) complexes containing adenine and guanosine

Guanosine (Guo) and adenine (Ade) zinc(II) complexes were synthesized by the reaction of the zinc(II) acetate and the respective base. Spectroscopic and thermal properties of the two complexes [Zn2(CH3COO)4(Guo)]·2H2O and [Zn(CH3COO)(Ade−)]·H2O (Ade−=adenine monoanion) are reported. Combination of thermal investigations with IR spectroscopy and powder XRD studies showed that pyrolysis of zinc(II) acetate took place in the first step of the thermal decomposition followed by release and pyrolysis of adenine or guanosine. The decomposition differs from those of zinc(II) carboxylates with N-donor organic molecules (nicotinamide, caffeine) studied elsewhere, in which the organic ligand is released in the first stage of decomposition followed by pyrolysis of the carboxylate.