Synthesis, crystal structure and DNA interaction studies of a 2D cadmium(II) coordination polymer constructed from 2-(2-pyridyl)benzimidazole

Exploring novel Cd(II) complexes with 5-methyl-4-imidazolecarboxaldehyde: synthesis, structure, computational insights, and affinity to DNA through switchSense methodology

A series of four Cd(II) complexes with 5-methyl-4-imidazolecarboxaldehyde (L) with different inorganic anions within or outside the coordination sphere of general formula: [CdCl2L2] (1), [CdBr2L2] (2), [CdI2L2] (3), and [CdL4](PF6)2·3H2O (4) was synthesized through one-step and two-step reactions, respectively. All complexes were obtained as colorless crystals without the need for recrystallization and exhibited solubility in aqueous solutions. Structural analysis revealed different coordination environments for each complex, with variations in bond lengths and angles. The crystal packing of the complexes was stabilized by hydrogen bonding and π-π stacking interactions. FT-IR analysis indicated coordination of the ligand to the metal ion, and UV-Vis studies confirmed the stability of the complexes in solution. Computational analysis has revealed the polar nature of the complexes and their favorable stability constants. Affinity studies with DNA using the switchSense technique demonstrated rapid association and dissociation processes for all complexes, with temperature-dependent binding constants. Thermodynamic analysis suggested spontaneous with positive entropy change and endothermic formation processes for the complexes. Overall, the study underscores the synthesis, examination, and interaction with DNA of Cd(II) complexes, demonstrating their promise within medicinal chemistry.

Synthesis and Photocatalytic Properties of Four Coordination Compounds Constructed from Two Benzimidazole-Based Asymmetric Polyazocyclic Ligands

In this paper, two benzimidazole derivative ligands were obtained using o-phenylenediamine and n-pyridine formaldehyde (n = 3, 4) by amine-aldol condensation reactions, which were reacted with selected inorganic metal salts by ambient temperature volatilization method to give compounds 1-4: {[(L1)₆]·[Cu₈I₈]} (1), {[L1]·[CuBr]·H₂O} (2), {[L2]·[CuBr]}_n(3), and {[(L2)₄]·[Cu₄I₄]} (4). They were characterized by IR, UV-Vis absorption spectroscopy, thermogravimetric analysis, and single crystal X-ray analysis. Simultaneously, compounds 1-4 were found to possess photocatalytic degradation of ciprofloxacin (CIP) by preliminary experimental investigations.

A novel binuclear hydrazone-based Cd(II) complex is a strong pro-apoptotic inducer with significant activity against 2D and 3D pancreatic cancer stem cells

A novel binuclear Cd complex (1) with hydrazone-based ligand was prepared and characterized by spectroscopy and single crystal X-ray diffraction techniques. Complex 1 reveals a strong pro-apoptotic activity in both human, mammary adenocarcinoma cells (MCF-7) and pancreatic AsPC-1 cancer stem cells (CSCs). While apoptosis undergoes mostly caspase-independent, 1 stimulates the activation of intrinsic pathway with noteworthy down regulation of caspase-8 activity in respect to non-treated controls. Distribution of cells over mitotic division indicates that 1 caused DNA damage in both cell lines, which is confirmed in DNA interaction studies. Compared to 1, cisplatin (CDDP) does not achieve cell death in 2D cultured AsPC-1 cells, while induces different pattern of cell cycle changes and caspase activation in 2D cultured MCF-7 cells, implying that these two compounds do not share similar mechanism of action. Additionally, 1 acts as a powerful inducer of mitochondrial superoxide production with dissipated trans-membrane potential in the majority of the treated cells already after 6 h of incubation. On 3D tumors, 1 displays a superior activity against CSC model, and at 100 μM induces disintegration of spheroids within 2 days of incubation. Fluorescence spectroscopy, along with molecular docking show that compound 1 binds to the minor groove of DNA. Compound 1 binds to the human serum albumin (HSA) showing that the HSA can effectively transport and store 1 in the human body. Thus, our current study strongly supports further investigations on antitumor activity of 1 as a drug candidate for the treatment of highly resistant pancreatic cancer.