Synthesis, characterization and biological activity of binuclear palladium(II) complexes

Two N,N,N′,N′-tetramethylethylenediamine (tmeda) protected palladium(II) complexes 1 and 2 were synthesized using two amide functionalized ligands L1 and L2 respectively. Complexes 1 and 2 were characterized by ¹H, ¹³C NMR, HH COSY, CH COSY and ESI-MS. Molecular structures of both the complexes were confirmed by single crystal X-ray diffraction of analogous complexes 1′ and 2′. Molecular packing in the crystal lattice was evaluated using Hirshfeld surface analysis. It was found that the H…H interaction is the major contributor to the molecular packing in complex 1′. However, in complex 2′, O…H/H…O short contact is the major stabilising factor of the crystal lattice. The biological activity of complexes 1′ and 2′ were evaluated using molecular docking tool. Both the complexes were found to interact with MexB protein and complex 2′ having higher binding affinity as evident from the binding energy values.