Simulation strategies for unusual EPR spectra of binuclear mixed-valence manganese complexes: synthesis, properties, and x-ray structures of the MnIIMnIII complexes [Mn2(bpmp)(.mu.-OAc)2](ClO4)2.cntdot.H2O and [Mn2(bcmp)(.mu.-OAc)2](ClO4)2.cntdot.CH2Cl2
作者:Habibe Diril、Hsiu Rong Chang、Mark J. Nilges、Xiaohua Zhang、Joseph A. Potenza、Harvey J. Schugar、Stephan S. Isied、David N. Hendrickson
DOI:10.1021/ja00196a013
日期:1989.7
group P2sub 1}/n with a = 12.493 (1) angstrom}, b = 21.583 (2) angstrom}, c = 16.631 (2) angstrom}, beta} = 95.31 (1)degree}, Z = 4; Rsub F} = 0.061 and Rsub wF} = 0.085 for 4298 unique reflections (I > 3sigma}(I)) at 297 (1) K. (Mnsub2}(bcmp)(mu}-OAc)sub2})(ClOsup minus}}sub4})sub2}center dot}CHsub2}Clsub2}, where bcmpsup minus}} is the monoanion of 2,6-bis(1,4,67-triazac
Acceleration of Hydrolytic DNA Cleavage by Dicopper(II) Complexes with<i>p</i>-Cresol-Derived Dinucleating Ligands at Slightly Acidic pH and Mechanistic Insights
Four dicopper(II) complexes, [Cu2(µ-X)(bcmp)](ClO4)2 [X = OH (1a) and X = Cl (1b)], [Cu2(µ-OH)(Me4bcmp)](ClO4)2 (2), and [Cu2(bcc)](ClO4)3 (3), were synthesized with three p-cresol-derived ligands,...
四种二铜 (II) 配合物,[Cu2(µ-X)(bcmp)](ClO4)2 [X = OH (1a) 和 X = Cl (1b)],[Cu2(µ-OH)(Me4bcmp)]( )2 (2) 和 [Cu2(bcc)]( )3 (3) 是用三个对甲酚衍生的配体合成的,...
DNA damage and induction of apoptosis in pancreatic cancer cells by a new dinuclear bis(triazacyclonane) copper complex
The dinuclear copper(II) complex [Cu-2bcmp(-H)}(mu-OH)](NO3)(2)center dot H2O (1, bcmp = 2,6-bis(1,4,7-triazacyclonon-1-ylmethyl)-4-methylphenol) has been synthesized and characterized by electrospray ionization mass spectrometry, potentiometric titration and cyclovoltammetry. The X-ray structure of the analogous perchlorate salt [Cu-2bcmp(-H)}(mu-OH)](ClO4)(2)center dot 2.5H(2)O (2) was determined. Cytotoxicity studies showed very promising activity of 1 against various pancreatic tumor cell lines with IC50 values comparable or even lower than those of cisplatin. The Cu complex displayed low toxicity against a human non-tumor cell line (HEM 293) demonstrating selectivity for cancer cells. 1 converts supercoiled pUC19 plasmid DNA into the nicked form at micromolar concentrations in the absence of added reductants. A detailed kinetic study on the hydrolysis of the DNA model bis(2,4-dinitrophenyl) phosphate (BDNPP) has been performed. 1 hydrolyses BDNPP with a second order rate constant of 0.047 M s(-1) at pH 8 and 40 degrees C. Finally, single cell electrophoresis (comet assay) and fluorescence microscopy analysis showed that 1 interacts with cellular DNA and induces apoptotic cell death of Capan-1 pancreatic cancer cells. Western blotting analysis indicated that the Cu complex activates the p53 dependent pathway of apoptosis. (C) 2015 Elsevier Inc. All rights reserved.
DNA binding, cleavage and cytotoxicity of a novel dimetallic Fe(III) triaza-cyclononane complex
A novel bimetallic Fe(III) complex with the bis(triaza-cyclononane) ligand 2,6-bis(1,4,7-triazacyclonon-1-ylmethyl)-4-methylphenol (bcmp) is reported. [Fe-2(bcmp(-H))(mu-OH)Cl-2]Cl-2 (2) contains two octahedral Fe(III) centers bound to the two triaza-cyclononane rings of bcmp. The coordination sphere is completed by one chlorine, one bridging phenolate oxygen and one bridging hydroxide group. The complex has been characterized by elemental analysis, Mossbauer spectroscopy, UV-Vis spectroscopy, pH potentiometric titration, ESI mass spectrometry and cyclic voltammetry. The complex hydrolyzes the DNA model bis (2,4-dinitrophenyl) phosphate (BDNPP) with a maximum activity a pH 7. Michaelis-Menten behavior is observed with k(cat) = 3.56 x 10(-4)s(-1) and K-m = 0.56 mM (pH 7.0, 40 degrees C). The interaction of 2 with CT DNA was studied by electronic absorption spectroscopy and gel electrophoresis. Notably, the complex relaxes supercoiled pUC19 DNA into the nicked form at low micromolar concentration (10 mu M) in the presence of an external reducing agent (ascorbic acid). Finally, the in vitro antiproliferative activity of 2 was assessed on a panel of human cancer cell lines and results revealed that the complex exhibited a significant cytotoxic effects in particular versus colon LoVo cancer cells, wih IC50 value 2.5 times lower than that shown by the reference metallodrug cisplatin (3.54 versus 8.53 mu M). (C) 2016 Elsevier B.V. All rights reserved.