Synthesis, Characterization and Antiviral Properties of Pd(II) Complexes With Penciclovir

With the aim to improve and extend the antiviral activity of the antiherpic drug penciclovir, to a wider spectrum of viruses, we have synthesized and characterized new binary and ternary complexes of Pd(II) of formulae cis-(pen)(2)PdCl(2) and cis,[(nucl)(2)Pd(pen)(2)]Cl(2), where nucl = guanosine, inosine, cytidine or penciclovir. The characterization was mainly based on IR and (1)H NMR spectroscopy, and the results showed that in all prepared complexes, penciclovir coordinates to the metal through N7. The far-i.r. spectrum of the complex cis-(pen)(2)PdCl(2) confirmed the cis- geometry around Pd(II). All the prepared complexes were markedly active against HSV-1 and HSV-2 strains, but not against thymidine kinase-deficient HSV-1 strains.