Chemosensor C1, namely, 3-acetoacetyl-7-hydroxycoumarin, was synthesized and exhibited highly selective and sensitive fluorescence sensing ability for Cu2+ over other metal ions under physiological conditions. The fluorescence quenching response of C1 for Cu2+ indicated that C1 can be used as an on-off fluorescent chemosensor to selectively detect Cu2+. The binding process was confirmed by UV–vis absorption, fluorescence measurement, mass spectroscopy, IR spectra and DFT calculation. To test the practical use of the probe, the determination of Cu2+ in real water samples was evaluated. The application of the fluorescent probe in monitoring intracellular Cu2+ in HeLa cells has also been demonstrated.

•A hydrazone derivative ligand has been used to construct functional MOFs.•Two MOFs are candidates for potential photoactive materials.•Three MOFs are excellent candidates as photocatalysts in decomposing MB.Three novel complexes, namely {[Zn3(L)2(SO4)2(H2O)4]·2H2O}n (1), {[Cd(L)(OAc)]}n (2) and [Hg2(L)(I)3]2 (3) (HL = N′ - isonicotinoylpyrimidine -2- carbohydrazonamide), have been synthesized and characterized by elemental analyses, infrared spectra and single-crystal X-ray diffraction analyze. The 1D complex 1 and complex 2, and the binuclear complex 3 are expanded to 3D networkers by the strong hydrogen bonds and π-π stacking interactions. The photocatalytic degradation of methylene blue (MB) results indicate that complexes 1–3 are excellent candidates as photocatalysts in decomposing MB with the presence of H2O2. In addition, the luminescent properties of these three complexes have been studied in the solid state.

The main theme of interest is to design functional metal–organic frameworks (MOFs) for exploring structural correlation with photocatalytic activity. So firstly, three different structural MOFs, namely, Cd(APAPT)2I2·2H2O (1) (APAPT = 3-(5-Amino-1H-pyrazol-4-yl)-5-(3-amino-1H-pyrazol-4-yl)-3,5-dihydro-[1,2,4]triazol-4-ylamine), [Mn(APAPT)(SO4)(H2O)]n (2) and {[Zn3(APAPT)2(SO4)(OH)2]·(H2O)}n (3) constructed by the same parasol-based ligands and different metal ions are reported here. Complex 1 shows one-dimensional chain linked by mononuclear Cd units through π⋯π interactions. Complex 2 possesses two-dimensional layer with left- and right-handed helical chains. Complex 3 with infinite Zn-cluster chains is a three-dimensional porous framework. The structural diversity indicates that the APAPT with different coordination modes play important roles in tuning the dimensionalities and structures of the title complexes. Photocatalytic studies show that the MB degradation rates were 63.2%, 51.3% and 80.3% for complexes 1–3, respectively. The results manifest that the more extended networks may aid in the transport of excited holes/electrons to the surface to initiate the photocatalytic decomposition reaction with MB. Besides, steric hindrance etc. helical chains or weaving structure may lead to a relative lower photocatalytic activity.Three different structural complexes have been constructed by parasol-based ligands and different metal ions for exploring structural correlation with photocatalytic activity.Download high-res image (125KB)Download full-size image

A novel two-fold interpenetrating network, namely, {[Zn(DPTMIA)]·(H2O)2(DMF)0.5}n (HPU-1), with rectangular channels was synthesized and structurally characterized. HPU-1 was shown to be potentially applicable as a multi-functional fluorescent probe. It was shown to specifically detect Fe3+, through a cation exchange mechanism, and hazardous phenol compounds, using a mechanism involving a decrease in the efficiency of the transfer of electrons and energy from the ligands to the metal ions. The detection limits of HPU-1 for Fe3+ and the phenol compounds were found to be lower than those of MOFs reported in the literature. This HPU-1 probe was shown to be functional in aqueous solution and to be affected neither by the type of solvent nor the pH.

A rhodamine derivative was synthesised via the hydrazone formation of rhodamine 6G hydrazide with 7-diethylamino-3-(1-hydroxy-3-oxobut-1-enyl)-2H-chromen-2-one. As a colourimetric and ratiometric fluorescent probe, the derivative exhibited high selectivity towards Cu2+ in neutral aqueous media. Moreover, the probe sensed Hg2+ with fluorescence enhancement at pH 10. The binding process was confirmed via UV-vis absorption, fluorescence measurements, 1H NMR, mass spectroscopy and density functional theory calculation. To validate the applicability of the probe, the probe was used to detect Cu2+ and Hg2+ ions in actual water samples. The application of the fluorescent sensor in monitoring intracellular Cu2+ in Hela cells has also been demonstrated.

•Four new complexes based on 3-ethyl-2-acetylpyrazine semicarbazone were synthesized and characterized.•The effect of the four complexes on human pancreatic cancer, gastric cancer and hepatic cancer cell lines were detected.•The complexes can inhibit cell proliferation and induce cell apoptosis in human cancer cell lines.Four new complexes based on L (where L = 3-ethyl-2-acetylpyrazine semicarbazone), namely [CoL2]Cl2·0.5H2O (1), [CoL2](NO3)2 (2), [CdL(H2O)2(NO3)](NO3)·H2O (3) and [CuL(CH3OH)Cl2]·[CuLCl2] (4) have been synthesized and characterized by X-ray diffraction analyses. The results show that the semicarbazone acts as a tridentate neutral ligand in all complexes. Each of complex 1 and 2 reveals a distorted octahedral geometry around the metal ion provided by two units of the ligand, while the ratio of the ligand and metal is 1:1 in complexes 3 and 4. The effect of complexes 1–4 on cell proliferation, apoptosis of human pancreatic cancer (Patu8988), human gastric cancer (SGC7901) and human hepatic cancer (SMMC7721) cell lines have been detected by MTT assay, Annexin V/PI double staining flow cytometry and TUNEL assay. The results show that complexes 1–4 can inhibit cell proliferation of Patu8988, SGC7901 and SMMC7721 cells, significantly higher than the effect of the ligand. However, the complex 4 reveals higher apoptosis rate, and displays up-regulated expression level of caspase 3, detected by western blotting, which also indicates the complex 4 can induce caspase-dependent cell apoptosis in SMMC7721.

•A new rhodamine-based fluorescent “off-on” probe for Al3+ has been developed.•The probe shows a high sensitivity and selectivity for Al3+.•Response of probe to Al3+ is a cation-catalyzed reaction.•The probe has been used for monitoring Al3+ in drinking water.A rhodamine derivative (R1) has been synthesized by a hydrazone formation of rhodamine 6G hydrazide with 3-methylthiophene-2-carbaldehyde, which exhibits high selectivity and sensitivity as an “off–on” fluorescent sensor toward Al3+ in water containing media. The binding process was confirmed by UV–vis absorption, fluorescence measurements, mass spectroscopy and DFT calculation. The probe functions by Al3+ induced hydrolytic cleavage of the imine-bond to produce an intense rhodamine-based emission. To test the practical use of the probe, the determination of Al3+ in real water samples was also evaluated.

•Two pyrrole containing Schiff base chemo-sensors were synthesized.•Each probe could act as colorimetric and fluorescent off on sensor to Zn2 +.•The detection limits of both sensors to Zn2 + are at the parts per million level.•Selective fluorescence sensing of Zn2 + ion via CN isomerization.•Both sensors have been applied in monitoring Zn2 + in real water samples.Two bis(pyrrol-2-yl-methyleneamine) chemo-sensors, 1, 3- and 1, 4-bis[3,4-dimethyl-5-ethyloxy -carbonyl-pyrrol-2-yl-methyleneamine]benzene (H2L1 and H2L2, respectively) have been synthesized and characterized, which exhibit high selectivity as off-on fluorescence sensors toward Zn2 + in CH3CN/H2O (9:1, v/v) solution. The detection limits of both sensors are at the parts per million level. Moreover, the probes H2L1 and H2L2 could sense Zn2 + by “naked eye” with a color change from colorless to yellow, and from yellow to dark yellow, respectively. To test the practical use of the probes, the determination of Zn2 + in real water samples was also evaluated.

•The biological activity of three dinuclear copper(II) complexes was investigated.•The three complexes can cause DNA damage.•Cell apoptosis was detected by AnnexinV/PI flow cytometry and Western blotting.•All the complexes can effectively induce apoptosis of the human tumor cells.Nowadays, chemotherapy is a common means of oncology. However, it is difficult to find excellent chemotherapy drugs. Here we reported three new ternary copper(II) complexes which have potential chemotherapy characteristics with reduced Schiff base ligand and heterocyclic bases (TBHP), [Cu(phen)(TBHP)]H2O (1), [Cu(dpz)(TBHP)]H2O (2) and [Cu(dppz)(TBHP)]H2O (3) (phen = 1,10-phenanthroline, dpz = dipyrido [3,2:2′,3′-f]quinoxaline, dppz = dipyrido [3,2-a:2′,3′-c]phenazine, H2TBHP = 2-(3,5-di-tert-butyl-2-hydroxybenzylamino)-2-benzyl-acetic acid). The DNA-binding properties of the complexes were investigated by spectrometric titrations, ethidium bromide displacement experiments and viscosity measurements. The results indicated that the three complexes, especially the complex 13, can strongly bind to calf-thymus DNA (CT-DNA). The intrinsic binding constants Kb of the ternary copper(II) complexes with CT-DNA were 1.37 × 105, 1.81 × 105 and 3.21 × 105 for 1, 2 and 3 respectively. Comparative cytotoxic activities of the copper(II) complexes were also determined by 3-(4,5-dimethylthiazol-2yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The results showed that the ternary copper(II) complexes had significant cytotoxic activity against the human lung cancer (A549), human esophageal cancer (Eca109) and human gastric cancer (SGC7901) cell lines. Cell apoptosis were detected by AnnexinV/PI flow cytometry and by Western blotting with the protein expression of p53, Bax and Bcl-2. All the three copper complexes can effectively induce apoptosis of the three human tumor cells.Three new ternary copper(II) complexes which have potential chemotherapy characteristics with reduced Schiff base ligand and heterocyclic bases, and the ternary copper(II) complexes had significant cytotoxic activity against the human cancer cell lines. They also can induce the cancer cell apoptosis.

•Three novel complexes were isolated and characterized by X-ray diffraction analyses.•The three complexes have excellent antitumor activities.•Cell apoptosis was detected by western blotting.Three novel complexes, [Cu4(L)4Cl4]·H2O (1), Zn(L)2 (2) and Cd(L)2 (3), based on HL (where HL = 2-acetylpyridine isonicotinohydrazone) were synthesized and characterized by X-ray diffraction analyses. In the tetranuclear complex 1, each copper(II) ion with a distorted square-planar coordination geometry is five-coordinated by one chloride anion, one ON2 donor set and one 4-pyridine nitrogen atom from another adjacent actylhydrazone ligand. However, the central ions in complexes 2 and 3 possess distorted octahedral coordination geometry, surrounded by two ON2 donor sets. In addition, all the complexes have excellent antitumor activity towards human lung cancer (A549) and human gastric cancer (SGC7901 and BGC823) cell lines. Furthermore, cell apoptosis induced by complex 1 was detected through TUNEL and Annexin V/PI staining with flow cytometric analysis and western blotting analysis.Three novel complexes, [Cu4(L)4Cl4]·H2O (1), Zn(L)2 (2) and Cd(L)2 (3), based on HL (where HL = 2-acetylpyridine isonicotinohydrazone) were synthesized and characterized by X-ray diffraction analyses. The cytotoxic apoptosis and western blotting were investigated.

Two isostructural hydrazide–hydrazone-based complexes, namely [Zn(L)(HL)(ClO4)]·H2O and [Ni(L)(HL)(ClO4)]·H2O (HL = 2-acetylpyridine isonicotinohydrazone), have been obtained and characterized by physicochemical and spectroscopic methods. In each complex, the first ligand is in the neutral keto form, while the second is in the deprotonated monoanionic enolate form. Both complexes have excellent antitumor activity toward A549 human lung cancer, and BGC823 and SGC7901 human gastric cancer cell lines. Furthermore, both complexes are active scavengers for O2−· and OH·, exerting superior activities compared to the free ligand.

•We investigate the biological activity of two new copper(II) complexes.•Drug 2 shows significant inhibitory effect to bacterial strains.•Drug 1 shows significant cytotoxic activities.Two novel Cu(II) complexes, [Cu(L)2(CH3OH)]·CH3OH (1) and [Cu(L)(DMF)Cl] (2) based on HL (where HL = 2-ethoxycarbonyl-5-formyl-3,4-dimethylpyrrole 4-hydroxylbenzoylhydrazone) were synthesized and characterized by X-ray diffraction analyses. The results show that in each complex, the acylhydrazone ligand is deprotonated and coordinated to the copper(II) ion via enolizated oxygen and imine nitrogen atoms. The central metal ion possesses a distorted square pyramidal and a square-planar coordination geometry in complexes 1 and 2, respectively. In addition, complex 2 shows obvious inhibitory effect to bacterial strains Staphylococcus aureus and Salmonella typhimurium, and complex 1 has excellent antitumor activity towards Hepatocellular carcinoma (Hep G2) cells (IC50 = 2.0 μM).Two novel Cu(II) complexes were synthesized and characterized. Complex 2 shows obvious inhibitory effect to bacterial strains, and complex 1 has excellent antitumor activity.