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In this work, we describe the synthesis of heterobimetallic Fe(II)/Pd(II) complexes bearing different halides and halide‐substituted butadienyl ligands. The synthetic approach involves the preparation of suitable Pd(II)‐butadienyl precursors containing a thioquinoline moiety, followed by the substitution of this relatively labile ligand with dppf (dppf=1,1′‐bis(diphenylphosphino)ferrocene). With the exception of complexes containing at least one iodine atom, all compounds were synthesized in high yields and purity, and thoroughly characterized using spectroscopic and diffractometric methods. The investigation of the antiproliferative activity of the synthesized organometallic complexes against ovarian and breast cancer cell lines revealed that all compounds exhibit noteworthy cytotoxicity, with IC50 values in the micromolar range and generally comparable to those of cisplatin. Interestingly, significant differences of cytotoxicity among the analysed compounds were observed in the case of MRC‐5 normal cells. Of particular interest is the dichloride derivative 3 a, which is essentially inactive towards non‐cancerous cells (IC50>100 μM), thus demonstrating promising in vitro selectivity that we believe warrants further investigation in the future. [ABSTRACT FROM AUTHOR]

This work presents the synthesis and full characterization of Pd(II)‐butadienyl complexes incorporating picolyl‐NHC or phosphine ligands (PPh3 or PTA). These complexes were evaluated against four different cancer cell lines and human lung fibroblasts. Our findings indicate a slightly lower antiproliferative activity of picolyl‐NHC Pd(II)‐butadienyl complexes compared to recently published ones featuring N−N, P−P, and C−C ligands but, above all, they exhibited selectivity for ovarian cancer cells. Additionally, trans‐[PdX (phosphine)2C4(COOMe)4Y)] derivatives (X=Br, Cl and Y=CH3, Br) proved excellent anticancer activity across all tested cancer cell lines, especially the bisPTA complexes. Importantly, the IC50 values suggest minimal impact from the halide coordinated to palladium or that present in the butadienyl terminal position. Furthermore, the low activity observed towards non‐cancerous cells underscores the potential of these synthesized Pd(II)‐butadienyl compounds as promising candidates for further investigation in anticancer research. [ABSTRACT FROM AUTHOR]

The search for new antineoplastic agents is imperative, as cancer remains one of the most preeminent causes of death worldwide. Since the discovery of the therapeutic potential of cisplatin, the study of metallodrugs in cancer chemotherapy acquired increasing interest. Starting from cisplatin derivatives, such as oxaliplatin and carboplatin, in the last years, different compounds were explored, employing different metal centers such as iron, ruthenium, gold, and palladium. Nonetheless, metallodrugs face several drawbacks, such as low water solubility, rapid clearance, and possible side toxicity. Encapsulation has emerged as a promising strategy to overcome these issues, providing both improved biocompatibility and protection of the payload from possible degradation in the biological environment. In this respect, liposomes, which are spherical vesicles characterized by an aqueous core surrounded by lipid bilayers, have proven to be ideal candidates due to their versatility. In fact, they can encapsulate both hydrophilic and hydrophobic drugs, are biocompatible, and their properties can be tuned to improve the selective delivery to tumour sites exploiting both passive and active targeting. In this review, we report the most recent findings on liposomal formulations of metallodrugs, with a focus on encapsulation techniques and the obtained biological results. [ABSTRACT FROM AUTHOR]

This review highlights significant advancements in antibody–drug conjugates (ADCs) equipped with metal-based and nature-inspired payloads, focusing on synthetic strategies for antibody conjugation. Traditional methods such us maleimide and succinimide conjugation and classical condensation reactions are prevalent for metallodrugs and natural compounds. However, emerging non-conventional strategies such as photoconjugation are gaining traction due to their milder conditions and, in an aspect which minimizes side reactions, selective formation of ADC. The review also summarizes the therapeutic and diagnostic properties of these ADCs, highlighting their enhanced selectivity and reduced side effects in cancer treatment compared to non-conjugated payloads. ADCs combine the specificity of monoclonal antibodies with the cytotoxicity of chemotherapy drugs, offering a targeted approach to the elimination of cancer cells while sparing healthy tissues. This targeted mechanism has demonstrated impressive clinical efficacy in various malignancies. Key future advancements include improved linker technology for enhanced stability and controlled release of cytotoxic agents, incorporation of novel, more potent, cytotoxic agents, and the identification of new cancer-specific antigens through genomic and proteomic technologies. ADCs are also expected to play a crucial role in combination therapies with immune checkpoint inhibitors, CAR-T cells, and small molecule inhibitors, leading to more durable and potentially curative outcomes. Ongoing research and clinical trials are expanding their capabilities, paving the way for more effective, safer, and personalized treatments, positioning ADCs as a cornerstone of modern medicine and offering new hope to patients. [ABSTRACT FROM AUTHOR]

Our search of new organopalladium compounds able to promote an effective antiproliferative action towards ovarian cancer cells continues. In this paper we have examined for the first time the anticancer activity of palladium imidoyl complexes, for which two different types of phosphines have been chosen as ancillary ligands: i) PTA and DAPTA to take advantage from their solubility in aqueous environment, and ii) dppf for combining the action of the Pd‐imidoyl fragment with that, well‐known, of ferrocene. The synthetic protocols as well as the exhaustive characterisation of the complexes through spectroscopic and diffractometric methods are described. In vitro tests carried out to assess the cytotoxicity of the new compounds towards two ovarian cancer cell lines (one cisplatin sensitive and the other cisplatin resistant) have revealed an interesting effect of the halide coordinated to the palladium centre (halogen effect). Moreover, all complexes have shown the same activity against the cisplatin‐sensitive (A2780) and cisplatin‐resistant (A2780cis) cell lines, suggesting a different mode of action with respect to the "classical" platinum‐based drugs. Finally, a selection of the most active compounds has shown an interesting selectivity towards ovarian cancer cells. [ABSTRACT FROM AUTHOR]

A wide range of platinum(0)-η2-(E)-1,2-ditosylethene complexes bearing isocyanide, phosphine and N-heterocyclic carbene ancillary ligands have been prepared with high yields and selectivity. All the novel products underwent thorough characterization using spectroscopic techniques, including NMR and FT-IR analyses. Additionally, for some compounds, the solid-state structures were elucidated through X-ray diffractometry. The synthesized complexes were successively evaluated for their potential as anticancer agents against two ovarian cancer cell lines (A2780 and A2780cis) and one breast cancer cell line (MDA-MB-231). The majority of the compounds displayed promising cytotoxicity within the micromolar range against A2780 and MDA-MB-231 cells, with IC50 values comparable to or even surpassing those of cisplatin. However, only a subset of compounds was cytotoxic against cisplatin-resistant cancer cells (A2780cis). Furthermore, the assessment of antiproliferative activity on MRC-5 normal cells revealed certain compounds to exhibit in vitro selectivity. Notably, complexes 3d, 6a and 6b showed low cytotoxicity towards normal cells (IC50 > 100 µM) while concurrently displaying potent cytotoxicity against cancer cells. [ABSTRACT FROM AUTHOR]

The mechanochemical syntheses of allyl and indenyl palladate complexes are reported. All compounds were obtained in quantitative yields and microanalytically pure without the need of any workup. These complexes are stable in chlorinated and polar (DMSO or DMSO/H2O solutions) solvents. In chlorinated solvents, they appear as ionic pairs of which crystals suitable for single X‐ray diffraction studies have been obtained. Bonding and solvation properties are rationalized through scalar relativistic DFT calculations. Moreover, most complexes showed excellent cytotoxicity towards ovarian cancer cell lines, with IC50 values comparable or lower than cisplatin. The potent anticancer activity of two IPrCl and IPr*‐based palladate complexes was examined in a high‐grade serous ovarian cancer (HGSOC) patient‐derived tumoroid. Moreover, the inhibition of the antioxidant enzyme thioredoxin reductase (TrxR) was noticed, and structure‐activity relationships could be derived, suggesting the ROS detoxifying system is involved in the mode of action. [ABSTRACT FROM AUTHOR]