Iron, copper and zinc ammonium-1-hydroxyalkylidene-diphosphonates with zero-, one- and two-dimensional covalent metal–ligand structures extended into three-dimensional supramolecular networks by charge-assisted hydrogen-bonding

A selective colorimetric chemosensor for detecting Ni(II) in aqueous solutions based on 4-[{[4-(3-chlorophenyl)-1,3-thiazol-2-yl]hydrazono}methyl]phenyl 4-methyl benzene sulfonate (CTHMBS)

Among the toxic heavy metals, Ni(II) can cause a variety of side effects on human health, such as allergy, cardiovascular and kidney diseases, lung fibrosis, lung, and nasal cancer. It is therefore critical from a public health and environmental perspective to determine and monitor Ni(II) ions in drinking water, foods, and environmental samples. In this study, a novel selective chemosensor (4-[{[4-(3-Chlorophenyl)-1,3-Thiazol-2-yl]Hydrazono}Methyl]phenyl4-methylBenzene Sulfonate (CTHMBS) was developed for the colorimetric detection of Ni(II) in aqueous medium. The presence of Ni(II) led to a distinct naked-eye color change from yellow to reddish-brown in aqueous solution. To examine the binding mechanism of CTHMBS to Ni(II), UV-vis spectroscopy analysis and DFT calculations were conducted. The detection limit of CTHMBS for Ni(II) was 11.87 µM, and the sensing ability of CTHMBS for Ni(II) was successfully carried out in real water samples.

The Fischer–Tropsch reaction in the aqueous phase over rhodium catalysts: a promising route to selective synthesis and separation of oxygenates and hydrocarbons

In the present communication, we uncovered the aqueous phase Fischer–Tropsch reaction over rhodium catalysts with high alcohol selectivity and separation of hydrocarbons and oxygenates into two phases.

Deciphering preferred solid-state conformations in nitrogen-containing bisphosphonates and their coordination compounds. A case study of discrete Cu(ii) complexes based on Cα-substituted analogues of zoledronic acid: crystal structures and solid-state characterization

Conformation diversity of N-containing bisphosphonic acids and related anions within their metal complexes and salts.

Ibandronate metal complexes: solution behavior and antiparasitic activity

To face the high costs of developing new drugs, researchers in both industry and academy are looking for ways to repurpose old drugs for new uses. In this sense, bisphosphonates that are clinically used for bone diseases have been studied as agents against Trypanosoma cruzi, causative parasite of Chagas disease. In this work, the development of first row transition metal complexes (M = Co²⁺, Mn²⁺, Ni²⁺) with the bisphosphonate ibandronate (iba, H₄iba representing the neutral form) is presented. The in-solution behavior of the systems containing iba and the selected 3d metal ions was studied by potentiometry. Mononuclear complexes [M(H_xiba)]^(2-x)- (x = 0-3) and [M(Hiba)₂]^4- together with the formation of the neutral polynuclear species [M₂iba] and [M₃(Hiba)₂] were detected for all studied systems. In the solid state, complexes of the formula [M₃(Hiba)₂(H₂O)₄]·6H₂O were obtained and characterized. All obtained complexes, forming [M(Hiba)]^- species under the conditions of the biological studies, were more active against the amastigote form of T. cruzi than the free iba, showing no toxicity in mammalian Vero cells. In addition, the same complexes were selective inhibitors of the parasitic farnesyl diphosphate synthase (FPPS) enzyme showing poor inhibition of the human one. However, the increase of the anti-T. cruzi activity upon coordination could not be explained neither through the inhibition of TcFPPS nor through the inhibition of TcSPPS (T. cruzi solanesyl-diphosphate synthase). The ability of the obtained metal complexes of catalyzing the generation of free radical species in the parasite could explain the observed anti-T. cruzi activity.

Aminobisphosphonates based on cyclohexane backbone as coordinating agents for metal ions. Thermodynamic, spectroscopic and biological studies

Complex formation equilibria of calcium, magnesium, copper and nickel with amino-bisphosphonic ligands are described, together with a speciation study along with calorimetric outcome and cytotoxicity characteristics.

Metal complexes of macrocyclic schiff-base ligand: preparation, characterisation, and biological activity

A new macrocyclic multidentate Schiff-base ligand Na4L consisting of two submacrocyclic units (10,21-bis-iminomethyl-3,6,14,17-tricyclo[17.3.1.1]tetracosa-1(23),2,6,8,10,12(24),13,17,19,21,-decaene-23,24-disodium) and its tetranuclear metal complexes with Mn(II), Co(II), Ni(II), Cu(II), and Zn(II) are reported. Na₄L was prepared via a template approach, which is based on the condensation reaction of sodium 2,4,6-triformyl phenolate with ethylenediamine in mole ratios of 2 : 3. The tetranuclear macrocyclic-based complexes were prepared from the reaction of the corresponding metal chloride with the ligand. The mode of bonding and overall geometry of the compounds were determined through physicochemical and spectroscopic methods. These studies revealed tetrahedral geometries about Mn, Co, and Zn atoms. However, square planar geometries have been suggested for Ni(II) and Cu(II) complexes. Biological activity of the ligand and its metal complexes against Gram positive bacterial strain Staphylococcus aureus and Gram negative bacteria Escherichia coli revealed that the metal complexes become more potentially resistive to the microbial activities as compared to the free ligand. However, these metal complexes do not exhibit any effects on the activity of Pseudomonas aeruginosa bacteria. There is therefore no inhibition zone.

A series of novel lanthanide carboxyphosphonates with a 3D framework structure: synthesis, structure, and luminescent and magnetic properties

By introduction of 1,4-benzenedicarboxylic acid as the second organic ligand, a series of novel lanthanide carboxyphosphonates with a 3D framework structure, namely, [Ln(3)(H(2)L)(HL)(2)(bdc)(2)(H(2)O)]·7H(2)O (Ln = La (1), Ce (2), Pr (3), Nd (4), Sm (5), Eu (6), Gd (7), Tb (8); H(3)L = H(2)O(3)PCH(2)NC(5)H(9)COOH; H(2)bdc = HOOCC(6)H(4)COOH) have been synthesized under hydrothermal conditions. Compounds are isostructural and feature a 3D framework in which Ln(III) polyhedra are interconnected by bridging {CPO(3)} tetrahedra into 2D inorganic layers parallel to the ab plane. The organic groups of H(2)L(-) are grafted on the two sides of the layer. These layers are further cross-linked by the bdc(2-) ligands from one layer to the Ln atoms from the other into a pillared-layered architecture with one-dimensional channel system along the a axis. The thermal stability of compounds has been investigated. Luminescent properties of compounds , and the magnetic properties of compound have also been studied.

Hydrothermal synthesis, structures, and luminescent properties of zinc(II) and cadmium(II) phosphonates with a 3D framework structure using terephthalate as second linkers

By introduction of 1,4-benzenedicarboxylic acid as a second organic ligand, two new divalent metal(II) phosphonates with a 3D framework structure, namely, [Zn(HL1)(bdc)(0.5)] (1) and [Cd(1.5)(HL2)(bdc)(0.5)] (2) (H(2)L1 = H(2)O(3)PCH(NH(2))C(6)H(5), H(3)L2 = H(2)O(3)PCH(2)-NC(5)H(9)-COOH, H(2)bdc = HOOCC(6)H(4)COOH), have been synthesized under hydrothermal conditions. The two compounds show three-dimensional (3D) framework structure with infinite two-dimensional (2D) networks pillared by H(2)bdc. For compound 1, the {ZnO(4)} polyhedra are interconnected by phosphonate groups into a 2D layer, and the adjacent layers are further cross-linked via the bdc(2-) anions to generate a three-dimensional framework structure with two types of channel system along the c-axis. A notable feature of compound 1 is the presence of alternate left- and right-handed helical chains in the structure. In compound 2, the inorganic chains, composed of {Cd(1)O(7)}, {Cd(2)O(4)} and {CPO(3)} polyhedra, are linked by HL2(2-) ligands to form a double layer structure in the ab plane, and the adjacent layers are further linked by the bdc(2-) anions to form a 3D framework structure with one-dimensional channel systems along the a-axis. Luminescence properties of compounds 1 and 2 have also been studied.