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Three new dinuclear Co(II) complexes [Co2(L1)2Cl2](PF6)2 (1), [Co2L2(OAc)2(CH3OH)4](ClO4)2 (2), and [Co2L3(OAc)2(CH3OH)4](ClO4)2 (3) were synthesized and structurally determined by X‐ray single‐crystal diffraction analysis as well as IR, elemental analysis, and mass spectrometry. All complexes exhibit efficiently self‐activated cleavage activity with hydrolytic mechanism, which was accurately proved by addition of regular radical scavengers, anaerobic cleavage experiment, and 2‐thiobarbituric acid reaction. Complex 1 exhibited higher selective cytotoxicity against tumor cells than normal cells, which is significantly better than that of cisplatin. Hoechst 33342 staining, intracellular ROS generation and mitochondrial membrane potential were conducted to assess the apoptosis‐inducing activity of 1. The effect of complex 1 on cell invasion was observed by Transwell assay and angiogenesis experiment, and the results demonstrated that 1 could inhibit the cell invasion and angiogenesis. [ABSTRACT FROM AUTHOR]

A novel and highly efficient dual-targeting PtII system was designed to improve the drug delivery capacity and selectivity in cancer treatment. The dual-targeting monofunctional PtII complexes (1–8) having glycosylated pendants as tridentated ligand were achieved by introducing glycosylation modification in the thioaminocarbazone compounds with potential lysosomal targeting ability. The structures and stability of 1–8 were further established by various techniques. Molecular docking studies showed that 2 was efficiently docked into glucose transporters protein 1 (GLUT1) and P-glycoprotein (Pgp) proteins with the optimal CDocker-interaction-energy of −64.84 and −48.85 kcal mol−1. Complex 2 with higher protein binding capacity demonstrated significant and broad-spectrum antitumor efficacy in vitro, even exhibiting a half maximal inhibitory concentration (IC50) value (∼10 μM) than cisplatin (∼17 μM) against human lung adenocarcinoma cells (A549). The inhibitor experiment revealed GLUT-mediated uptake of 2, and the subcellular localization experiment in A549 also proved that 2 could be localized in the lysosome, thereby causing cell apoptosis. Moreover, cellular thermal shift assay (CETSA) confirmed the binding of 2 with the target proteins of GLUT1 and Pgp. The above results indicated that 2 represents a potential anticancer candidate with dual-targeting functions. [ABSTRACT FROM AUTHOR]

Two chiral Cu(II) complexes of [Cu2( R-L)2](PF6)2·2C2H5OH ( 1) and [Cu2( S-L)2](PF6)2·2C2H5OH ( 2) (HL = 2-(Bis(quinolin-2-ylmethyl)amino)-1-propanol) were designed and synthesized to serve as chemical nucleases and anticancer drugs. X-ray crystallography revealed that two complexes contain chiral binuclear cations and PF6− anions. The interaction of two complexes with CT-DNA was researched via various spectroscopic techniques and viscosity measurement, indicating that the complexes were bound to CT-DNA by a classical intercalation binding mode. In addition, the two complexes exhibited remarkable DNA cleavage activity with an optimal dosage of 10 μM in the absence of any exogenous oxidant agent. Both of the complexes showed excellent in vitro cytotoxicity on A549 cell lines with IC50 values in the low micromolar range. Moreover, complex 2 could damage DNA of A549 cells into fragmentation and then induced cell apoptosis in a dose-dependent manner, which was demonstrated by comet assay and Hoechst 33342 staining experiment. Further research showed that complex 2 could also induce G2 and S phase cell cycle arrest. [ABSTRACT FROM AUTHOR]

The employment of a reduced Schiff-base ligand, 1,3-bis(3-methoxy-salicylamino)-2-propanol (H3L), with the assistance of acetate anions led to the isolation of eight heptanuclear heterometallic complexes containing [Cu5Ln2] cores. Single-crystal X-ray diffraction analyses have been performed for all the complexes and show that they all have dicationic [Cu5Ln2] cores with two nitrate or hexafluorophosphate anions to compensate the charge. The dicationic parts in 1–8 display centrosymmetric hexagonal-like arrangements in which one CuII ion sits on the inversion centre with six peripheral metal ions (two LnIII and four CuII) around it. The magnetic susceptibilities of all the complexes have been studied by dc magnetic measurements. The temperature dependent magnetic susceptibility data for the CuII–GdIII complex have been processed using PHI software. The results reveal that the magnetic exchange interactions between CuII and CuII ions are antiferromagnetic while those between CuII and GdIII ions are ferromagnetic. The magnetostructural correlations reveal that the bridging angles of Cu–O–Cu and Cu–O–Gd greatly influence the magnetic coupling of CuII–CuII and CuII–GdIII, respectively. Further, ac susceptibility studies have been carried out for DyIII and TbIII complexes and HoIII derivatives. The complexes CuII–HoIII and CuII–TbIII show slow magnetization relaxation behaviour of an SMM. [ABSTRACT FROM AUTHOR]

A series of NiII, CoII, ZnII and CdII complexes 1–9 with polytopic Schiff base ligands have been synthesized. The single-crystal X-ray crystallography results show that tetranuclear complexes 1–6 have common face-shared defective dicubane cores, whereas trinuclear CdII complexes 7–9 are almost linear entities. Synthesis methods (solvent evaporation and hydrothermal synthesis), reaction conditions (pH, solvents and dosage) and coligands (azide, methanol, chloride and acetate) play vital roles in determining the final structure of the complexes and therefore their magnetic properties. In complexes 1–6, the terminal and central M2+ ions are connected through mixed bridges, μ-phenoxido/μ1,1,1-X and μ-Oalphatic/μ1,1,1-X, while central two M2+ ions are linked by double bridges, μ1,1,1-X (X = azido and methoxido groups for 1 and 2–6 respectively). For complex 1, two central NiII ions are connected through two μ1,1,1-N3− which is relatively less reported. For complexes 7–9, there are two kinds of CdII, the centre CdII ions are eight-coordinated with triangle dodecahedral geometries, while the two side CdII ions are six-coordinated with trigonal prism geometries using chlorides or acetates as terminal ligands. Magnetic susceptibility measurements (χM) for compounds 1–6 have been performed, and they reveal predominant ferromagnetic exchange interactions in CoII and NiII tetramers. The photoluminescence studies show that the ZnII complex 6 and three CdII complexes 7–9 have strong fluorescence, and the lifetimes are measured to be in the 102 nanosecond timescale. [ABSTRACT FROM AUTHOR]

Two new chiral mononuclear Mn(III) complexes, [Mn L( R)Cl (C2H5OH)]•C2H5OH ( 1) and [Mn L( S) (CH3OH)2]Cl•CH3OH ( 2), {H2 L = ( R, R)-or ( S, S)-N,N'-bis-(2-hydroxy-1-naphthalidehydene)-cyclohexanediamine} were synthesized and characterized by various physicochemical techniques. Bond valence sum (BVS) calculations and the Jahn-Teller effect indicate that the Mn centers are in a +3 oxidation state. The statuses of the two complexes in the solution were confirmed as a pair of enantiomers by electrospray ionization, (ESI-MS) spectrum. The binding ability of the complexes with calf thymus CT-DNA was investigated by spectroscopic and viscosity measurements. Both of the complexes could interact with CT-DNA via an intercalative mode with the order of 1 ( R-enantiomer) > 2 ( S-enantiomer). Under the physiological conditions, the two compounds exhibit efficient DNA cleavage activities without any external agent, which also follows the order of R-enantiomer > S-enantiomer. Interestingly, the concentration-dependent DNA cleavage experiments indicate an optimal concentration of 17.5 μM. In addition, the interaction of the compounds with bovine serum albumin (BSA) was also investigated, which indicated that the complexes could quench the intrinsic fluorescence of BSA by a static quenching mechanism. Chirality 27:142-150, 2015. © 2014 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Six complexes with chiral Schiff‐base ligands containing TPP+ groups, [VOLR,R/S,S](ClO4)2(1 for RR, 2 for SS), [NiLR,R/S,S](ClO4)2·C2H5OH (3 for RR, 4 for SS) and [CuLR,R/S,S](ClO4)2·CHCl3·CH3CH2OH (5 for RR, 6 for SS) (LR,R/S,S = N,N′‐Bis{5‐[(triphenylphosphonium)‐methyl]salicylidine}‐(1R,2R/1S,2S)‐diphenylethane‐1,2‐diamine, were synthesized to serve as mitochondrion‐targeting anticancer drugs. The introduction of TPP+ group(s) might markedly influence the properties of complexes. Compounds 3 and 5 were structurally characterized by X‐ray crystallography. Complexes 1–6 could be moderate intercalating agents to CT‐DNA which is determined by several spectroscopy methods. DNA cleavage experiments revealed that all compounds could promote oxidative cleavage of pBR322 plasmid DNA in the presence of H2O2. MTT assay indicated 1–6 exhibited effective cytotoxicity on A549 and MCF‐7 cell lines. Notably, the IC50 values of 5 (1.24 ± 0.33 μM) or 6 (1.47 ± 0.52 μM) were approximately 9–11 fold lower than that of cisplatin (IC50 = 13.56 ± 0.88 μM) on A549 cells. 5 and 6 were picked for further study, which indicated that the cytotoxicity seems to result from multiple mechanisms of action, including effectively suppress the growth and proliferation of A549 cells, generation of reactive oxygen species, dissipation of mitochondrial membrane potential, cell cycle perturbation and apoptosis induction. Compounds 1–6 could highly accumulate in the mitochondria by means of ICP‐MS assay. This study demonstrates that 1–6 with mitochondrion‐targeting function could be efficient anticancer drugs. [ABSTRACT FROM AUTHOR]

A novel and highly efficient dual-targeting Pt II system was designed to improve the drug delivery capacity and selectivity in cancer treatment. The dual-targeting monofunctional Pt II complexes (1-8) having glycosylated pendants as tridentated ligand were achieved by introducing glycosylation modification in the thioaminocarbazone compounds with potential lysosomal targeting ability. The structures and stability of 1-8 were further established by various techniques. Molecular docking studies showed that 2 was efficiently docked into glucose transporters protein 1 (GLUT1) and P-glycoprotein (Pgp) proteins with the optimal CDocker-interaction-energy of -64.84 and -48.85 kcal mol -1 . Complex 2 with higher protein binding capacity demonstrated significant and broad-spectrum antitumor efficacy in vitro , even exhibiting a half maximal inhibitory concentration (IC 50 ) value (∼10 μM) than cisplatin (∼17 μM) against human lung adenocarcinoma cells (A549). The inhibitor experiment revealed GLUT-mediated uptake of 2, and the subcellular localization experiment in A549 also proved that 2 could be localized in the lysosome, thereby causing cell apoptosis. Moreover, cellular thermal shift assay (CETSA) confirmed the binding of 2 with the target proteins of GLUT1 and Pgp. The above results indicated that 2 represents a potential anticancer candidate with dual-targeting functions.

Two new chiral mononuclear Mn((III)) complexes, [MnL((R)) Cl (C2 H5 OH)]•C2 H5 OH () and [MnL((S)) (CH3 OH)2 ]Cl•CH3 OH (), {H2 L = (R,R)-or (S,S)-N,N'-bis-(2-hydroxy-1-naphthalidehydene)-cyclohexanediamine} were synthesized and characterized by various physicochemical techniques. Bond valence sum (BVS) calculations and the Jahn-Teller effect indicate that the Mn centers are in a +3 oxidation state. The statuses of the two complexes in the solution were confirmed as a pair of enantiomers by electrospray ionization, mass spectrometry (ESI-MS) spectrum. The binding ability of the complexes with calf thymus CT-DNA was investigated by spectroscopic and viscosity measurements. Both of the complexes could interact with CT-DNA via an intercalative mode with the order of (R-enantiomer) > (S-enantiomer). Under the physiological conditions, the two compounds exhibit efficient DNA cleavage activities without any external agent, which also follows the order of R-enantiomer > S-enantiomer. Interestingly, the concentration-dependent DNA cleavage experiments indicate an optimal concentration of 17.5 μM. In addition, the interaction of the compounds with bovine serum albumin (BSA) was also investigated, which indicated that the complexes could quench the intrinsic fluorescence of BSA by a static quenching mechanism., (Copyright © 2014 Wiley Periodicals, Inc.)