Silver dithiocarbamates derived from amino acid esters

We report herein a series of new silver compounds with dithiocarbamate ligands derived from amino acid esters (AAE-DTCs). Compounds [Ag{SSC-N(R')(CH₂R''COOR)}]_n (Ag(L1)-Ag(L5); N-dithioato-diethyliminodiacetate (L1), -ethyl-sarcosinate (L2), -tert-butyl-sarcosinate (L3), -methyl-L-prolinate (L4), -ethyl-N-benzylglycinate (L5)) were synthesised from in situ generated AAE-DTCs by salt metathesis with silver nitrate. The isolated products were characterised by different analytical techniques. Ag(L1), Ag(L4), and Ag(L5) were accessible to single-crystal X-ray structure determination, comprising hexameric subunits linked by dimeric units into a 1D-polymeric structure (Ag(L1)) and more homogeneous ribbon-like polymeric structures (Ag(L4) and Ag(L5)). DOSY NMR measurements and supporting DFT calculations were carried out to elucidate the structure of these compounds in solution, showing evidence for smaller agglomerates like dimers and tetramers. Additionally, as first evaluation of the biological activity of these complexes, ethidium bromide displacement assays and DNA melting curve experiments were carried out, the results showing moderate DNA binding abilities.