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The structure of the title compound, [CdCl₂(C₁₅H₁₆N₄S)], at 100 K has monoclinic (P2₁/c) symmetry. The compound has a layer structure and is a 1:1 complex of the organic ligand and cadmium chloride. The ligand, 3,3-dimethyl-1-[(E)-[phenyl(pyridine-2-yl)methylidene]amino]thiourea (L, Bp44mT), is of interest with respect to anticancer activity, antiviral properties and potential use in conditions of iron overload, from hemochromatosis or from multiple transfusions in hematological disorders such as sickle cell disease or beta thalassemia. This study is aimed at uncovering the basis of selectivity of the ligand as a chelator and for lead optimization. We also examine the ligand's potential use in treating heavy metal poisoning from cadmium, arsenic, lead or mercury, and for environmental remediation. The crystal structure exhibits no intermolecular or intramolecular hydrogen bonding with the supramolecular features being driven by hydrophobic, π–π and long-range dispersion forces. 

In the centrosymmetric title complexes, di-μ-acetato-bis({N,N-dimethyl-2-[phenyl(pyridin-2-yl)methylidene]hydrazine-1-carbothioamidato}zinc(II)), [Zn₂(C₁₅H₁₅N₄S)₂(C₂H₃O₂)₂] (I), and di-μ-acetato-bis({N-ethyl-2-[phenyl(pyridin-2-yl)methylidene]hydrazine-1-carbothioamidato}zinc(II)), [Zn₂(C₁₆H₁₇N₄S)₂(C₂H₃O₂)₂] (II), the zinc ions are chelated by theN,N,S-tridentate ligands and bridged by pairs of acetate ions. The acetate ion in (I) is disordered over two orientations in a 0.756 (6):0.244 (6) ratio, leading to different zinc coordination modes for the major (5-coordinate) and minor (6-coordinate) disorder components. Geometrical indices [τ₅= 0.32 and 0.30 for (I) (major component) and (II), respectively] suggest the zinc coordination in these phases to be distorted square pyramidal. This study forms part of our aim to discern the mechanism of metal binding in these chelators, their specificity and selectivity, and to gain insight into the role of cellular zinc in physiological processes such as infection, immunity and cancer. 

Disrupted iron balance causes anemia and iron overload leading to hypoxia and systemic oxidative stress. Iron overload may arise from red blood cell disorders such as sickle cell disease, thalassemia major and primary hemochromatosis, or from treatment with multiple transfusions. These hematological disorders are characterized by constant red blood cell hemolysis and the release of iron. Hemolysis is a continuous source of reactive oxygen species whose accumulation changes the redox potential in the erythrocyte, the endothelium and other tissue causing damage to organ systems. Iron overload and its consequences can be treated with iron chelating therapy. We have carried out structural studies of small molecule ligands that were previously reported for their iron chelating ability. The chelators were analyzed using mass spectrometry, proton nuclear magnetic resonance and infrared spectroscopy. The iron chelators, 2-benzoylpyridine-4,4-dimethyl-3-thiosemicarbazone, 3-ethyl-1-{[2-phenyl-1-(pyridin-2-yl)ethylidene]amino}thiourea and 1-{[2-phenyl-1-(pyridin-2-yl)ethylidene]amino}-3-(prop‑2-en-1-yl)thiourea in their unbound conformation were crystallized and their structures were determined. This work addresses the evolution of a thiosemicarbazone class of iron chelators by analyzing and comparing the structure and properties of a series of closely related molecules, relating these to their in vitro activity thus providing valuable update to the search for newer, better and more effective iron chelators and metal-based therapeutics. 

During the course of exploring crystallization conditions in generating metal–organic frameworks (MOFs) for use in the crystalline sponge method, two discrete metal–organic complexes, namely, aqua[2,4,6-tris(pyridin-4-yl)-1,3,5-triazine]zinc(II) bromide, [Zn(C₁₈H₁₂N₆)(H₂O)]Br₂, and aqua[2,4,6-tris(pyridin-4-yl)-1,3,5-triazine]zinc(II) chloride, [Zn(C₁₈H₁₂N₆)(H₂O)]Cl₂, were encountered. Structures in the orthorhombic space groupPnma(No. 62) for the bromide congener at 299 K and the chloride congener at 100 K were obtained. A phase transition for the bromide congener occurred upon cooling from 299 to 100 K, yielding a crystal polymorph with four domains that exhibits monoclinicP2₁/mspace-group symmetry (No. 11), which arises from conformational changes. The main intramolecular contacts that contribute to the crystal packing in all observed structures are H...H, Halide...H/H...Halide, C...H/H...C, and N...H/H...N. Intramolecular hydrogen bonding between the Zn-bound water and non-Zn-bound pyridyl N atoms is a prominent feature within the three-dimensional networks. Aromatic π-stacking between the non-Zn-bound pyridine rings and contacts involving the halide ligands further stabilize the crystal packing.