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Cobalt(III) complexes containing both optically active tetradentate Schiff base ligands, (SB=Salen, MeOSalen, t-Bu-Salen) with axial ligands (L) [Co(SB)L2]ClO4 (L=imidazole (Im), 2-methylimidazole (2-MeIm), 1-methylimidazole (MeIm)) have been prepared and characterized. In addition, the crystal structures of [Co(Salen)(MeIm)2]ClO4 (1c), [Co(MeOSalen)(MeIm)2]ClO4 (2c), and [Co(t-Bu-Salen)(MeIm)2]ClO4 (3c) have been determined by X-ray structure analysis. The properties of these hexacoordinate complexes, such as electronic absorption, circular dichroism spectra, and 1H NMR spectra, have been studied. [Copyright &y& Elsevier]

Graphical abstract Luminescent MOF nanosheets with thicknesses of only 4 nm were used as fluorescent sensor to construct the sensing systems of H 2 O 2 and glucose and activity assay of glucose oxidase. Highlights • A cation-exchange mediated sonication method is used to exfoliate MOF to nanosheets. • The thickness of MOF nanosheets is only 4 nm, ensuring their good dispersibility. • With MOF nanosheets as sensor, an enzyme assisted method is designed to analyze H 2 O 2. • This method can be advanced by multi-enzyme catalysis to sense H 2 O 2 related species. • A glucose detection method and a glucose oxidase assay are developed based on it. Abstract 2D metal-organic framework (MOF) nanosheets have emerged as a novel kind of sensing materials due to the large external surface area and accessible active sites on the surface. In this work, we successfully prepared luminescent MOF nanosheets (In-aip) with thickness of 4 nm by the cation-exchange mediated sonication of a 2D connected anionic MOF. Using In-aip as fluorescent sensor, an enzyme assisted system was established for the analysis of H 2 O 2 with the quenching effect of the oxidation product on its emission. The nanosheet morphology of In-aip ensures its high capture efficiency of unstable intermediate, so high sensitivity was achieved (detection limit = 0.87 μM). With high sensitivity and wide quantitative range, this H 2 O 2 sensing system could be used as a universal platform for the analysis of H 2 O 2 related biomolecules and enzymes. By multi-enzyme cascade catalysis, a detection method of glucose and an activity assay of glucose oxidase were developed based on it. This work is the first example of using luminescent MOF nanosheets to bioanalysis and shows their wide application potential. [ABSTRACT FROM AUTHOR]

Au, Se and porphyrin are widely used components in the design of anticancer drugs, but their combination has never been referred to. In this work, a Se-modified porphyrin Au(III) complex, [AuTPP-Se]Cl, was designed and synthesized as a potential anticancer agent. This compound exhibits remarkable antiproliferative activity on all the six tested cancer cells. Its potency on HepG2 is even ten times higher than that of CDDP. The synergistic action among Au, Se and porphyrin components was validated. Mechanism study showed that both the induction of mitochondria-dependent apoptosis and the arrest of cell cycle contribute to the anticancer activity of [AuTPP-Se]Cl. [ABSTRACT FROM AUTHOR]

Highlights: [•] DFT calculations on porphine/C60 bisadducts were carried out. [•] Pyrrolidine ring appended on C60 has influence on its interaction with porphine. [•] Interaction was found between pyrrolidine ring appended on C60 and porphyrin. [•] Charger transfer between pyrrolidine ring and porphine was observed. [•] The red shift of absorption was predicted for fullerene/porphine complexes. [ABSTRACT FROM AUTHOR]

Abstract: Two C 2-symmetrical hexaazatriphenylene (HAT) derivatives, 2,3-diphenyl-6,7,10,11-tetra(pyridin-2-yl)dipyrazino[2,3-f:2′,3′-h]quinoxaline (1) and 2,3,6,7-tetraphenyl-10,11-di(pyridin-2-yl)dipyrazino[2,3-f:2′,3′-h]quinoxaline (2), were designed and synthesized by the condensation reaction of 1,2-diamines and 1,2-diketones. Both compounds 1 and 2 exhibit sensitive, ratiometric and colorimetric fluorescence selectivity for Zn2+ ion over alkali ions, alkaline earth ions and a wide range of transition metal ions upon excitation at 350nm in acetonitrile/water. The interactions between 1 or 2 and Zn2+ can be observed by naked eyes with an obvious color change of the solution from colorless to yellow. For fluorescence intensity of 2 toward Zn2+, a good linearity (correlation coefficient R 2=0.993) was established with a detection limit of 0.095μM, which is more sensitive than that of 1 (0.2μM). The binding modes of the free ligands 1 and 2 with Zn2+ are discussed in context to their photophysical and electrochemical properties as well as single X-ray crystallographic structures of 1, 2 and 1-Zn. [Copyright &y& Elsevier]