Organomercury(II) complexes of 6-thioguanine: synthesis, characterization, and biological studies

Organomercury(II) complexes involving 6-thioguanine, of the type p-XC6H4HgL (Fig. 1) [LH = 6-thioguanine; X = Me, MeO, NO2], have been synthesized and characterized. Conductance measurements indicate that the complexes are nonelectrolytes. From IR and UV studies, it is concluded that 6-thioguanine acts as a bidentate ligand, coordinating through the 6-thione group and deprotonation of N-7. 1H and 13C NMR support the stoichiometry of the complexes. From thermal studies (TG and DSC) various kinetic and thermodynamic parameters for thermal degradation have been enumerated. In addition, the fragmentation pattern of the complexes have been analyzed on the basis of mass spectra. The p-MeC6H4HgL and p-MeOC6H4HgL complexes display significant activity against L1210 leukemia cells.