Metal derivatives of thiosemicarbazones: crystal and molecular structures of mono- and di-nuclear copper(I) complexes with N1-substituted thiosemicarbazones

Novel mono-, bi-, tri- and tetra-nuclear copper complexes that inhibit tumor growth through apoptosis and anti-angiogenesis

To develop the next-generation metal agents for efficiently inhibiting tumor growth, a series of novel mononuclear, binuclear and trinuclear copper (Cu) thiophene-2-formaldehyde thiosemicarbazone complexes and a tetranuclear Cu 1,2,4-triazole-derived complex have been synthesized and their structure-activity relationships have been studied. The trinucleated Cu complex showed the strongest inhibitory activity against T24 cells among all the Cu complexes. Its antitumor effect in vivo was superior to that of cisplatin, with reduced side effects. Further studies on the antitumor mechanism have showed that Cu complexes not only induced apoptosis of cancer cells but also inhibited tumor angiogenesis by inhibiting the migration and invasion of vascular endothelial cells, blocking the cell cycle in the G1 phase, and inducing autophagy.

Synthesis, characterization, and biological properties of mono-, di- and poly-nuclear bismuth(III) halide complexes containing thiophene-2-carbaldehyde thiosemicarbazones

In order to investigate the coordination chemistry and pharmacological applications of bismuth compounds, a series of new bismuth(III) halide thiosemicarbazone complexes were synthesized. The reactions of thiophene-2-carbaldehyde-N-substituted thiosemicarbazones with bismuth(III) halides resulted in the formation of the {[[BiCl₂(η¹-S-Httsc)₄]⁺.Cl^-][BiCl₂(μ₂-Cl)(η¹-S-Httsc)₂]₂} (1), {[BiCl₃(η¹-S-Htmtsc)₃].CH₃OH} (2), {[BiCl₃(η¹-S-Htetsc)₃].CH₃OH} (3), {[BiBr₂(μ₂-Br)(η¹-S-Httsc)₂]₂.CH₃OH} (4), {[BiBr₂(μ₂-Br)(η¹-S-Htmtsc)₂]_n} (5), and {[BiI₂(μ₂-I)(η¹-S-Httsc)₂]₂} (6) complexes (Httsc: thiophene-2-carbaldehyde thiosemicarbazone, Htmtsc: thiophene-2-carbaldehyde-N-methyl thiosemicarbazone, Htetsc: thiophene-2-carbaldehyde-N-ethyl thiosemicarbazone). The complexes were characterized by a number of different spectroscopic techniques and the crystal structures of all bismuth(III) complexes (1-6) were determined by using single crystal X-ray diffraction study. In addition, the thermal stability of the complexes was compared using Thermogravimetric-differential thermal analysis. Crystal structures of the two free ligands, thiophene-2-carbaldehyde-N-methyl-thiosemicarbazone and thiophene-2-carbaldehyde-N-ethyl-thiosemicarbazone, were also determined by using single crystal X-ray diffraction analysis. The Hirshfeld surface of the bismuth(III) complexes and free ligands were additionally analyzed to verify the intermolecular interactions. Biological studies showed that all six bismuth(III) thiosemicarbazone complexes (1-6) exhibited biological activities against selected bacteria and the human breast adenocarcinoma (MCF-7) cell line.