Cell nucleus localization and high anticancer activity of quinoline-benzopyran rhodium(III) metal complexes as therapeutic and fluorescence imaging agents.

Four novel rhodium(III) complexes, [RhIII(QB1)Cl3(DMSO)] (RhN1), [RhIII(QB2)Cl3(CH3OH)]·CH3OH (RhN2), [RhIII(QB3)Cl3(CH3OH)]·CH3OH (RhS), and [RhIII(QB4)Cl3(DMSO)] (RhQ), bearing quinoline-benzopyran ligands (QB1-QB4) were synthesized and used to develop highly anticancer therapeutic and fluorescence imaging agents. Compared with the QB1-QB4 ligands (IC50 > 89.2 ± 1.7 µM for A549/DDP), RhN1, RhN2, RhS and RhQ exhibit selective cytotoxicity against lung carcinoma cisplatin-resistant A549/DDP (A549CDDP) cancer cells, with IC50 values in the range of 0.08-2.7 µM. The fluorescent imaging agent RhQ with the more extended planar QB4 ligand exhibited high anticancer activity in A549CDDP cells and was found in the cell nucleus fraction, whereas RhS had no fluorescence properties. RhQ and RhS may trigger cell apoptosis by causing DNA damage and initiating the mitochondrial dysfunction pathway. Furthermore, RhQ has a higher antitumor efficacy (ca. 55.3%) than RhS (46.4%) and cisplatin (CDDP, 33.1%), and RhQ demonstrated significantly lower toxicity in vivo than CDDP, making it a promising Rh(III)-based anticancer therapeutic and fluorescence imaging agent.

A Multifunctional Lanthanide Carbonate Cluster Based Metal-Organic Framework Exhibits High Proton Transport and Magnetic Entropy Change.

A novel multifunctional, three-dimensional (3D) lanthanide carbonate cluster based metal-organic framework (MOF) with the general formula {[Gd2(CO3)(ox)2(H2O)2]·3H2O} n (1) has been synthesized via self-assembly of gadolinium (Gd) carbonate and oxalate under hydrothermal conditions. Single-crystal X-ray diffraction reveals that the compound 1 consists of the Gd carbonate cluster with oxalic acid ligands, which form a 3D framework structure with an ordered one-dimensional (1D) pore channel along the a-axis. The coordination water molecules of Gd3+ ions point to the interior of the pore and form a 1D hydrogen bond pathway with oxygen atoms in adjacent oxalic acid that is stable at high temperature (up to 150 °C). The compound 1 features multiple hydrogen-bonding walls and good thermal stabilities, and shows the highest proton conductivity of 1.98 × 10-3 S cm-1 at T = 150 °C and in room air without additional humidity. Magnetic investigations of compound 1 demonstrate that weak antiferromagnetic couplings between adjacent Gd3+ ions bring about large cryogenic magnetocaloric effects. Remarkably, the maximum entropy change (-Δ Sm) of compound 1 reaches 58.5 J kg-1 K-1 at 2 K for a moderate field change (Δ H = 7 T). Moreover, the isomorphous MOFs: {[Ln2(CO3)(ox)2(H2O)2]·3H2O} n (Ln3+ = Ce3+(2), Pr3+(3), Nd3+(4), Tb3+(5)) also are structurally and functionally characterized, and compounds 2-5 exhibit proton conductivity above 10-3 S cm-1 in room air and without additional humidity.

Bis[2,4-dichloro-6-(ethyl-imino-meth-yl)phenolato-κN,O]nickel(II).

In the title compound, [Ni(C(9)H(8)Cl(2)NO)(2)], the Ni(II) ion lies on an inversion centre and is coordinated in a slightly distorted square-planar geometry by an N and an O atom from two symmetry-related bidentate 2,4-dichloro-6-(ethyl-imino-meth-yl)phenolate ligands. In the crystal structure, there are short Cl⋯Cl distances of 3.506 (1) and 3.350 (1) Å.