Synthesis of substituted terpyridine nickel nitrate complexes and their inhibitory selectivity against cancer cell lines.

Six terpyridine­nickel complexes 1-6 were formed by the coordination of 4'-(4-R-phenyl)-2,2':6',2″-terpyridine (R = hydroxyl (L1), methoxyl (L2), methylsulfonyl (L3), fluoro (L4), bromo (L5), iodo (L6)) derivatives to nickel nitrate. The compositions and structures of these complexes were analyzed by Fourier Transform infrared spectroscopy (FT-IR), elemental analyses, electrospray ionization mass spectra (ESI-MS), solid-state ultraviolet-visible (UV-Vis) spectroscopy, and single crystal X-ray diffraction (1, 2 and 4) studies. In vitro anticancer cell proliferation experiments against SiHa (human cervical squamous cancer cell line) cells, Bel-7402 (human hepatoma cancer cell line), Eca-109 (human esophageal cancer cell line) and HL-7702 (human normal hepatocyte cell line) indicate that they have more excellent anti-proliferation effects than the cis-platin against Siha cells, Bel-7402 cells and Eca-109 cells. Especially, complex 5 showed a rather outstanding inhibitory effect against the SiHa cell line and was less toxic than the other compounds to the HL-7702 cell line, implying an obvious specific inhibitory effect. Therefore, complex 5 has the potential value to be developed as an anticancer cell-specific drug against human cervical squamous carcinoma. Molecular docking simulation, UV-vis absorption spectroscopy and circular dichroism experiments show that they prefer to bind to DNA part in an embedded binding manner.

Fe(II) complexes of 2,2':6',2''-terpyridine ligands functionalized with substituted-phenyl groups: synthesis, crystal structures and anticancer potential.

With the aim of developing potential anticancer drug candidates, a series of Fe(II) complexes were synthesized using nine 2,2':6',2''-terpyridine ligands functionalized with substituted-phenyl groups, and their biological activities were systematically investigated. Their bis-terpyridine sandwich-like structures were determined by single crystal X-ray crystallography. In vitro antiproliferative experiments based on three human cancer cell lines, including human hepatoma cancer cell line (Bel-7402), human esophageal cancer cell line (Eca-109), and human cervical squamous cancer cell line (SiHa), indicate the high antiproliferation activities of these complexes compared with commercial cisplatin. And their toxicity to normal cells was estimated based on human normal hepatocyte (HL-7702) cell line. In particular, when the phenyl in terpyridine ligand was modified by a carboxyl group, the corresponding complex 3 exhibited much higher antiproliferation to cancer Bel-7402 cells (IC50 = 3.653 µmol L-1) than cisplatin and low toxicity to normal HL-7702 cells (IC50 = 99.92 µmol L-1), implying a significant selectivity for 3 in killing hepatoma cancer cells. Combined with the fact that iron element is more accessible than platin, this series of Fe(II) complexes comprises potential candidates for anticancer drugs with specific inhibition of hepatoma cancer. UV titration experiments and circular dichroism (CD) showed a strong binding affinity between these nine complexes and CT-DNA. However, molecular docking simulation revealed the competitive binding of DNA and protein to these complexes. Further, the interactions between these complexes and bovine serum albumin (BSA) have been studied by fluorescence titration and CD spectroscopy.

Correction: Silver complexes with substituted terpyridines as promising anticancer metallodrugs and their crystal structure, photoluminescence, and DNA interactions.

Correction for 'Silver complexes with substituted terpyridines as promising anticancer metallodrugs and their crystal structure, photoluminescence, and DNA interactions' by Jiahe Li et al., Dalton Trans., 2023, 52, 9607-9621, https://doi.org/10.1039/D2DT03463H.

Silver complexes with substituted terpyridines as promising anticancer metallodrugs and their crystal structure, photoluminescence, and DNA interactions.

Six silver hexafluoroantimonate complexes (1-6) with 4'-(4'-substituted-phenyl)-2,2':6',2''-terpyridine compounds bearing hydrogen (L1), methyl (L2), methylsulfonyl (L3), chloro (L4), bromo (L5) and iodo (L6) were prepared and characterized by 1H NMR, 13C NMR, IR, elemental analysis and single crystal X-ray diffraction. All the compounds exhibit interesting photoluminescence properties in the solid state and solution. In vitro data demonstrate that all of them show higher antiproliferative activities than cisplatin against three human carcinoma cell lines, A549, Eca-109 and MCF-7. Compound 3 exhibits the lowest IC50 value (2.298 µM) against A549 cell lines, which is 2.963 µM for 4 against Eca-109 and 1.830 µM for 1 against MCF-7. For silver halogen-substituted terpyridine compounds, their anticancer activities decrease following the sequence of -Cl, -Br, and -I substituents. The comparison results show that their anticancer activity is significantly higher than that of their free ligands. The DNA interaction was studied by fluorescence titration, circular dichroism spectroscopy and molecular modeling methods. Spectrophotometric results reveal that the compounds have strong affinity binding with DNA as intercalators and molecular docking studies indicate that the binding is contributed by the π-π stacking and hydrogen bonds. The DNA binding ability of the complexes has been correlated with their anticancer activities, which could potentially provide a new rationale for the future design of terpyridine-based metal complexes with antitumor potential.

Enhance the removal and immobilization of Cd(II) by the synthesis in situ of dithiocarbamate-geopolymer microsphere composite.

In this study, slag-based geopolymer microspheres (SGS) were combined with dithiocarbamate (DTC) to synthesize the composite adsorbent of SGS and DTC in situ (SGS-DTC). Synthesis was carried out with optimal dosages of 10 mL of EDA, 1.0 g of SGS, and 20 mL of CS2. The differences in material properties, performance, and mechanisms in the adsorption and immobilization of toxic Cd(II) in water between SGS and SGS-DTC were investigated. SGS-DTC showed better adsorption performance than SGS, irrespective of adsorbent dosage, pH, original content, and contact duration. Although after the Cd(II) adsorption, the immobilization performance at a different pH was better in the SGS-DTC than in the SGS, the immobilization performance was unaffected by changes in the other factors. For static adsorption, the adsorption rate of SGS-DTC (1.5 h) was faster than that of SGS (6 h); the Cd(II) adsorption capacity of SGS-DTC (211.2 mg/g) was almost twice that of SGS (116.7 mg/g), and correspondingly, the removal rate of SGS-DTC (99.75%) was nearly twice that of SGS (53.2%). For dynamic adsorption, the adsorption capacity of SGS-DTC was 389.78 mg/g, which is considerably higher than that of SGS (293.38 mg/g) in the Cd(II) solution prepared with deionized water. Furthermore, the adsorption capacity of the SGS-DTC was 299.26 mg/g, which is significantly higher than that of SGS (150.03 mg/g) in the Cd(II) solution prepared by the river water from Yongjiang, Nanning, Guangxi, China. One reason is that DTC was able to activate Si-O-Si without adsorption performance within SGS, thereby improving its adsorption and purification properties significantly. The other reason is that, after anchoring DTC on SGS, the specific surface area varied from 34.05-146.47 m2/g, the morphology was smooth-leaf-like, the pore volume was 0.13-0.20 cm3/g, and the pore size in SGS, was 14.75-5.60 nm. The high potential of SGS-DTC in removing and immobilizing heavy metal materials in wastewater is demonstrated in the results.

Synthesis, characterization, photoluminescence, anti-tumor activity, DFT calculations and molecular docking with proteins of zinc(ii) halogen substituted terpyridine compounds.

Reactions between halogen substituted terpyridine ligands F- (L1), Cl- (L2), Br- (L3) and I-4'-phenyl-terpyridine (L4) and ZnBr2 or ZnI2 led to the formation of complexes [Zn(Br)2L1] (1), [Zn(i)2L1] (2), [Zn(Br)2L2] (3), [Zn(i)2L2] (4), [Zn(Br)2L3] (5), [Zn(i)2L3] (6), [Zn(Br)2L4] (7), and [Zn(i)2L4] (8), respectively, which were characterized by elemental analysis, 1H NMR, IR and single crystal X-ray diffraction. Their photoluminescence properties, solution stabilities, hydrophilicity/lipophilicity properties and anti-proliferative activity against three cancer cell lines as well as structure-function relationships are analyzed. All the complexes, which show high solution stabilities and lipophilicity under determination conditions, reveal much higher antiproliferative activities than cisplatin against the human lung carcinoma cell line (A549), human hepatocellular carcinoma cell line (Bel-7042) and human breast cancer cell line (MCF-7) in vitro. Fluorescence spectroscopy and circular dichroic analysis reveal that the compounds have strong affinity binding with ctDNA and stack onto the base pairs of the ctDNA. The results obtained are further explained in terms of the electronic properties of the compounds by density functional theory (DFT) calculations, and it is found that the halogen anions play critical roles in the antitumor activity of these compounds. Their affinities to HSP90 proteins, ALK, EGFR and HER2 kinases and the binding sites on these proteins have been determined by computational docking analysis, and the results indicate that the only form of their binding is van der Waals forces.

Study on the Photoluminescent and Thermal Properties of Zinc Complexes with a N6O4 Macrocyclic Ligand.

Reactions between a N6O4 macrocyclic ligand (L¹) and several Zn(II) salts (trifluoromethane sulfonate, p-toluenesulfonate, acetate, benzoate, o-, m- or p-hydroxybenzoate) led to the formation of seven complexes, [Zn2L¹ (DMSO)4](OSO2CF3)4 (1), [Zn2(p-OSO2PhCH3)4L¹] (2), [Zn2(OCOCH3)4L¹] (3), [Zn2(OCOPh)4L¹] (4), [Zn2(o-OCOPhOH)4L¹] (5), [Zn2(m-OCOPhOH)4 L¹] (6) and [Zn2(p-OCOPhOH)4 L¹] (7), which were characterized by elemental analysis, ¹H-NMR, 13C-NMR, IR, fluorescence spectroscopies and single crystal X-ray diffraction. In 1, the Zn atom is pentacoordinated with a N3O2 irregular trigonal bipyramidal coordination environment, like the geometries in compounds 3⁻7, whereas in structure 2 the metal atom is envisaged as possessing a distorted N3O3 octahedronal environment. All the compounds show interesting photoluminescent properties in solid states and solutions in DMF and DMSO, which are reported along with their TG-DTA thermal decomposition processes, UV-vis absorption spectroscopy and fluorescence quantum yields in DMF and DMSO.

[Determination of trace gold by on-line enrichment flow injection flame atomic absorption spectrometry with N1923 levextrel resin].

A new method for the determination of micro amount of gold with N1923 levextrel resin by flow injection on-line separation and flame atomic absorption spectrometry is described. Au (III) absorbed on the resin can be eluted quantitatively using sulphuric-urea solution. The absorption is carried out in 1.0 mol.L-1 HCl medium and the enhancement factor of 32 is achieved for a loading period of 90 s. The detection limit is 0.001 microgram.mL-1. The flow rate of sample injection, the time of extraction, the flow rate of enrichment, the concentration and acidity of eluting and the effect of coexistence element are studied by flame atomic absorption spectrometry. The recoveries of Au are 98.3%-101%. The developed method has been applied to the determination of trace gold in water samples with satisfactory results.