Non-classical N-metallated Pd(II) pincer complexes featuring amino acid pendant arms: Synthesis and biological activity

Palladium(II) Pincer Complexes of Functionalized Amides with S-Modified Cysteine and Homocysteine Residues: Cytotoxic Activity and Different Aspects of Their Biological Effect on Living Cells

“…As a confirmation of our rationale, the analogues of complexes I bearing histidine pendant arms with N-donor ancillary groups (compounds II , Figure ) were shown to exhibit very low antiproliferative activity against several human cancer cell lines or even facilitated the growth of cancer cells . Another avenue used to modify the ligand framework was the variation of an acid component (N-modification) . The resulting pincer complexes with S,N,S- and S,N,P-donor sets (compounds III – V ) appeared to be inferior in cytotoxic activity to their S,N,N-counterparts I derived from picolinylamides .…”

“…6 Another avenue used to modify the ligand framework was the variation of an acid component (N-modification). 10 The resulting pincer complexes with S,N,S-and S,N,P-donor sets (compounds III−V) appeared to be inferior in cytotoxic activity to their S,N,N-counterparts I derived from picolinylamides. 6 Finally, palladium(II) pincer complexes that featured a complementary S,N,N-coordination but were deprived of amino acid residues (compounds VI and VII) also displayed lower cytotoxic effects in comparison to I.…”

Halide exchange studies of novel Pd(ii) NNN-pincer complexes

“…While formation of a carbon-palladium bond provides stability, replacing carbon with other elements such as Si, P, N have been shown to lead to signicant changes in reactivity and an lead to signicant developments in catalysis 4,8,[21][22][23][24][25][26][27] and cytotoxicity studies. 18,20,[28][29][30][31][32] A key factor in reactivity is the general lability of the fourth coordination site. For instance, the nature of the monodentate ligand (L) at the fourth coordination site has been shown to provide remarkable control over the electronic structures of palladium and platinum complexes with NCN pincer ligands.…”

Design of pincer complexes based on (methylsulfanyl)acetic/propionic acid amides with ancillary S‐ and N‐donors as potential catalysts and cytotoxic agents

“…Their counterparts with dianionic ligand frameworks were found to be key intermediates in various palladium‐catalysed CH functionalization processes, including regio‐ and stereoselective reactions, which give access to complex natural products and biologically active compounds (complexes V – VII ) . Furthermore, a series of Pd(II) pincer complexes with N‐heterocyclic carbene donor moieties or ancillary amino acid residues displayed promising cytotoxic activity against several human cancer cell lines (compounds VIII – XI ).…”

“…In recent years, our research group has extended a range of pincer‐type palladocycles based on functionalized carboxamides with several series of complexes (see, for example, Scheme ) [3c,d,4c,7a,8,9]. Some of them demonstrated pronounced cytotoxic effects against human colon (HCT116), breast (MCF7) and prostate (PC3) cancer cells (compounds XII and XIII );[7a,8] others exhibited moderate to high catalytic activity in Suzuki cross‐coupling (compounds XIV – XVI ) . The performed investigations allowed us to outline preliminary tendencies in the structure–activity relationships.…”