Synthesis and characterization of new derivatives of bis(1,4‐diazepinium) salts and bis(γ‐substituted pentamethine cyanine(dyes using vinamidinium salt

New-Generation Heterocyclic Bis-Pentamethinium Salts as Potential Cytostatic Drugs with Dual IL-6R and Mitochondria-Targeting Activity

IL-6 signaling is involved in the pathogenesis of a number of serious diseases, including chronic inflammation and cancer. Targeting of IL-6 receptor (IL-6R) by small molecules is therefore an intensively studied strategy in cancer treatment. We describe the design, synthesis, and characteristics of two new bis-pentamethinium salts 5 and 6 (meta and para) bearing indole moieties. Molecular docking studies showed that both compounds have the potential to bind IL-6R (free energy of binding −9.5 and −8.1 kcal/mol). The interaction with IL-6R was confirmed using microscale thermophoresis analyses, which revealed that both compounds had strong affinity for the IL-6R (experimentally determined dissociation constants 26.5 ± 2.5 nM and 304 ± 27.6 nM, respectively). In addition, both compounds were cytotoxic for a broad spectrum of cancer cell lines in micromolar concentrations, most likely due to their accumulation in mitochondria and inhibition of mitochondrial respiration. In summary, the structure motif of bis-pentamethinium salts represents a promising starting point for the design of novel multitargeting compounds with the potential to inhibit IL-6 signaling and simultaneously target mitochondrial metabolism in cancer cells.

Synthesis of new allylidene amino phenol-containing Schiff bases and metal complex formation using trimethinium salts

An efficient route for the synthesis of novel Schiff bases from the condensation reaction of 2-substituted 1,3-bis(dimethylamino)-trimethinium salts with diverse aminophenols in the presence of triethylamine in EtOH at reflux is described. Complexes of transition metals with Schiff base ligand (L) 3c, having the donor atom set N₂O₂, were studied. The ultraviolet spectral behavior of the complexes in DMSO was investigated and the λ_max of these compounds was examined. The structure of the new compounds was confirmed based on their spectral data from IR, ¹H NMR and ¹³C NMR, mass spectra, and elemental analysis.

An efficient route for the synthesis of novel Schiff bases from the condensation reaction of 2-substituted 1,3-bis(dimethylamino)-trimethinium salts with diverse aminophenols in the presence of triethylamine in EtOH at reflux is described.