Influence of the Reaction Conditions in the Crystal Structures of Zn(II) and Ni(II) Coordination Compounds with a Dissymmetric Bis(Thiosemicarbazone) Ligand

New Tin (IV) and Organotin (IV) Complexes with a Hybrid Thiosemicarbazone/Hydrazone Ligand: Synthesis, Crystal Structure, and Antiproliferative Activity

Nowadays, the search for new chemotherapeutic agents with low toxicity and high selectivity is a major concern. In this paper, we report the synthesis and characterization of a hybrid thiosemicarbazone/hydrazone ligand in its neutral form (L1H2) and as the chloride salt ([L1H3]Cl)-, three diorganotin (IV) complexes, and one complex with Sn (IV). The compounds have been fully characterized by IR, mass spectra, 1H, 13C, and 119Sn NMR, 119Sn CP/MAS NMR, and by single crystal X-ray diffraction. The organotin compounds have the empirical formula [SnR2L1] (R = Me, Bu, and Ph), but in the solid state, they are polymeric species with seven coordination number due to weak coordination of the pyridine nitrogen, whereas in solution, the polymeric structure is lost to afford hexacoordinate monomeric species. Reaction with SnI4 yields complex [Sn (L1)2]·EtOH, with the metal in a distorted dodecahedral arrangement. We have evaluated the antiproliferative activity of the two forms of the ligands and the four coordination compounds against MDA-MB-231, HeLa, PC3, and HepG2 cancer cell lines, and WI-38 normal cell line, and all the compounds present higher activity than cisplatin, used as the standard control. To investigate the mode of action, we have selected the most active complex, containing phenyl substituents, and used the triple negative breast cancer cell line MDA-MB-231. The results show that the complex induces apoptotic cell death promoted by generation of reactive oxygen species and by disruption of mitochondrial membrane potential.

Synthesis, crystal structure and Hirshfeld surface analysis of (2Z,2'E)-2,2'-(3-meth-oxy-3-phenylpropane-1,2-diyl-idene)bis-(hydrazine-1-carbo-thioamide) di-methyl-formamide monosolvate

The overall mol-ecular configuration of the title compound, C12H16N6OS2·C3H7NO, is stabilized in the solid state by intra-molecular C-H⋯N, C-H⋯O, N-H⋯N and N-H⋯O inter-actions, forming S(5) ring motifs. In the crystal, mol-ecules are linked to each other and solvent di-methyl-formamide mol-ecules by N-H⋯S, N-H⋯O, C-H⋯O and C-H⋯S hydrogen bonds, forming a three dimensional network. The phenyl ring of the title compound is disordered over two sites with an occupancy ratio of 0.57 (4):0.43 (4). A Hirshfeld surface analysis was performed to qu-antify the contributions of the different inter-molecular inter-actions, indicating that the most important contributions to the crystal packing are from H⋯H (38.7%), S⋯H / H⋯S (24.0%), C⋯H / H⋯C (18.5%) and N⋯H / H⋯N (9.8%) inter-actions.

Hydrolysis of a carbamate triggered by coordination of metal ions

The mechanism of carbamate activation promoted by different metal ions has been explored in this work. The reaction of the carbamate ligand H2L with chloride metal salts (M = Ni,...