Synthesis and spectroscopic properties of two different structural Schiff base Zn(II) complexes constructed with/without auxiliary ligands

In vitro and in vivo antiproliferative activity on lung cancer of two acylhydrazone based zinc(II) complexes

Two acylhydrazone based zinc(II) complexes [Zn(HL)2Cl2(CH3OH)2] (Zn1) and [ZnL(AC)]2 (Zn2) were synthesized from 3-(1-(salicyloylhydrazono)ethyl) pyridine (HL). Single crystal X-ray structure analyses showed that complexes Zn1 and Zn2 have a zero-dimensional monomer or dimer structure. Antiproliferative activity studies revealed that Zn1 and Zn2 are both more effective against A549 cells than cisplatin. The results of the reactive oxygen species (ROS) generation assay on A549 cells showed that both Zn1 and Zn2 induced apoptosis through ROS accumulation. The apoptosis-inducing and cell cycle arrest effects of Zn1 and Zn2 on A549 cells indicated that the antitumor effect was achieved through apoptosis induction and inhibition of DNA synthesis by blocking the G0/G1 phase of the cell cycle. What's more, the results of wound-healing assay showed that Zn1 and Zn2 could inhibit the migration of A549 cells. Western blot analysis further demonstrated that Zn1 and Zn2 induced cell apoptosis through the mitochondrial pathway, in which process, the expression level of cytochrome C, cleaved-PARP, cleaved-caspase 3 and cleaved-caspase 9 proteins increased while pro-caspase 3 and pro-caspase 9 expression decreased. In vivo anticancer evaluation demonstrated that both Zn1 and Zn2 complexes effectively inhibited tumor growth without causing significant toxicity in systemic organs.

Synthesis, Crystal Structure, Hirschfeld Surface Analysis and Catalytic Activity of a New Binuclear Zn(II) Complex Based on Homophthalic Acid and 2,2'-Bipyridine Ligands

A new binuclear Zn(II) complex, [Zn2L2(BIPY)2(H2O)2](1) (H2L = homophthalic acid, BIPY = 2,2'-bipyridine) has been synthesized by one-pot method of homophthalic acid, 2,2'-bipyridine, zinc acetate dihydrate, and NaOH in water/ethanol (v:v = 1:1) solution. The structure of complex (1) was characterized by IR and X-ray single-crystal diffraction analysis. The results show that each Zn(II) ion is five-coordinated with two carboxylic O atoms from two homophthalate ligands (O2, O3 or O2a, O3a), two N atoms from two 2,2'-bipyridine ligands (N1, N2 or N1a, N2a) and one O atom from coordinated water molecule (O5 or O5a), and forms a distorted trigonal bipyramid coordination geometry. Complex (1) forms 1D chained structure and 3D network structure by the p-p interaction of 2,2'-bipyridine ligands. The Hirschfeld surface analysis of complex (1) was calculated. The catalytic performance of complex (1) has also been investigated for the oxidation of benzyl alcohol under O2 atmosphere. The optimal reaction temperature and pressure were 100 °C and 0.3 MPa for complex (1). Copyright © 2022 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0). 

A highly selective and sensitive salamo-salen-salamo hybrid fluorometic chemosensor for identification of Zn2+ and the continuous recognition of phosphate anions

A salamo-salen-salamo hybrid fluorescent chemical sensor (H₄L) was synthesized and characterized. It exhibits high selectivity and sensitivity to Zn²⁺ in physiological pH range. Meanwhile, its zinc(II) complex (L-Zn²⁺) continuously responses phosphate anions in DMF/H₂O (v/v, 9:1) solution. Moreover, the identification processes are explored using characterization methods such as UV-absorption spectra, IR spectra and ESI-MS spectrum. In addition, the coordination mechanism of H₂PO₄^- and Zn²⁺ were successfully exploited to make the chemical sensor reproducible. In short, the sensors H₄L and L-Zn²⁺ will be promising detection devices for Zn²⁺ and phosphate anions.

A dual-channel 'turn-on' fluorescent chemosensor for high selectivity and sensitivity detection of CN¯ based on a coumarin-Schiff base derivative in an aqueous system

Novel strategies still need to be proposed that can be used to identify and detect toxic environmental pollutants. In this paper, two channels of colorimetry and fluorescence 'turn-on' fluorescent probe 1 (7-hydroxy-8-[(2-hydroxy-phenylimino)- methyl]-4-methylbenzopyran-2-one) for the simple yet highly selective detection of CN¯ have been successfully designed and synthesized. Crystal features of probe 1 were defined using X-ray single crystal diffractometry. Probe 1 showed a strongly colorimetric and fluorescence response to CN¯ that induced obvious naked-eye colour changes in aqueous solution (DMSO/H₂ O, 3:1 v:v). In addition, probe 1 for CN¯ detection displayed low detection limits of 3.91 × 10^-8  M, which were significantly lower than the 1.9 × 10^-6  M maximum level specified by the World Health Organization (WHO) for potable water. The sensing mechanism for probe 1 was attributed to the deprotonation process as shown by ¹ H NMR titration. Moreover, based on the visible colorimetry and fluorescence change for probe 1 to CN¯, measurement was performed for simulated water samples containing CN¯. This study provides a broad prospect for solving other pollution problems and promoting the design of new fluorescent materials.

Synthesis and crystal structure of poly[(μ3-2-(2-carboxylatophenyl)-1H-benzo[d]imidazole-5-carboxylato-κO,O′:O′;:O″, O″′)-(μ2-1-(4-(1Himidazol-1-yl)phenyl)-1H-imidazole-κ2N:N′)cadmium(II)], C27H18CdN6O4

C27H18CdN6O4, triclinic, P 1 ‾ $P‾{1}$ (no. 2), a = 10.2994(8) Å, b = 10.7795(7) Å, c = 11.0038(7) Å, α = 89.778(5)°, β = 78.046(6)°, γ = 83.049(6)°, Z = 2, V = 1186.11(14) Å3, R gt (F) = 0.0402, wR ref (F 2) = 0.0809, T = 293 K.

A Highly Selective Turn-on Fluorescent and Naked-eye Colourimetric Dual-channel Probe for Cyanide Anions Detection in Water Samples

A highly selective turn-on fluorescent and naked-eye colourimetric dual-channel probe for cyanide anions (CN-) has been designed and characterized. In the mixed solution (DMSO / H₂O, 9:1, v / v), only CN- could cause an increase in the UV absorption intensity and the corresponding fluorescence intensity increased, and other anions had no significant effect on the probe. After treatment with cyanide in the probe solution, the solution showed a noticeable colour change, from light yellow to purple. Moreover, a fluorescence spectrophotometer can be used to observe that the fluorescence intensity of the solution is significantly enhanced. The response of the colourimetric and fluorescent dual-channel probe to CN- was attributed to nucleophilic addition, and the mechanism was determined by ¹H NMR spectroscopy. In addition, this probe was used to detect CN- in actual water samples, including river water, drinking water, and tap water. The spiked CN- recovery rate is very high (97.2%-100.06%), and analytical precision is also very high (RSD < 2%), which shows its feasibility and reliability for detecting cyanide ions in actual water samples.

Two novel tetraphenylethylene-skeleton salamo-type fluorescent probes: specific recognition of cyanide through different response patterns

The possible sensing mechanism of probes TPES1 and TPES2 towards CN− ions.

A highly efficient yet stable salamo-type fluorescent chemosensor with multiple responses to Cu2+ and S2−

A new salamo-type compound H3L has been synthesized, and exploited as a chemosensor with multiple responses to Cu2+ and S2−. The crystal structure of the Cu(ii)  complex has been determined by X-ray crystallographic analysis.