Spectral, electrical conductivity and biological activity properties of some new azopyrimidine derivatives and their complexes

The electronic absorption spectra of 5-(o-substituted phenylazo)-6-amino-2-thiouracils and 6-(o-substituted phenylazo)-5-aminouracils containing different substituents are studied at different pH's. The dissociation constants are evaluated and discussed. Phenomenon of tautomerism is more supported by 1H NMR and 13C NMR spectra. The electrical conductivity of some ligands and their CoII, NiII and CuII complexes in the temperature range 293-150 K favoured their semiconducting properties where the metal ion forms a bridge to facilitate the flow of the current. The biological activity of some ligands and their complexes are tested against a number of Gram-positive and Gram-negative bacteria. The results showed that some of the compounds have a well considerable activity against some of the organisms.