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Two new water-soluble copper(II) complexes, [Cu(dmphen)(2)(NO3)]NO3 (1), [Cu(dmphen)(tyr)(H2O)] NO3 center dot H2O (2) and the diquartemary salt of dmphen (dmphen = 4,7-dimethyl-1,10-phenanthroline and tyr = L-tyrosine), have been synthesized and characterized by elemental analysis, H-1 NMR, C-13 NMR and IR spectroscopy, thermal analysis and single crystal X-ray diffraction techniques. The CT-DNA binding properties of these compounds have been investigated by absorption, emission spectroscopy and thermal denaturation measurements. The supercoiled pBR322 plasmid DNA cleavage activity of these compounds has been explored by agarose gel electrophoresis. The cytotoxicity of these compounds against MCF-7, Caco-2, A549 cancer cells and BEAS-2B healthy cells was also studied by the XTT method. Complexes 1 and 2 exhibit significant cytotoxicity, with lower IC50 values than those of cisplatin.

New copper(II) complexes-dimeric-[Cu(nphen)(gly)(H2O)](+) (1) and [Cu(dmphen)(gly)(NO3)(H2O)] (2) (nphen = 5-nitro-1,10-phenanthroline, dmphen = 4,7-dimethyl-1,10-phenanthroline, and gly = glycine)-have been synthesized and characterized by CHN analysis, single-crystal X-ray diffraction techniques, FTIR, EPR spectroscopy, and cyclic voltammetry. The CT-DNA-binding properties of these complexes have been investigated by thermal denaturation measurements and both absorption and emission spectroscopy. The DNA cleavage activity of these complexes has been studied on supercoiled pUC19 plasmid DNA by gel electrophoresis experiments in the absence and presence of H2O2. Furthermore, the interaction of these complexes with bovine serum albumin (BSA) has been investigated using absorption and emission spectroscopy. The thermodynamic parameters, free-energy change (Delta G), enthalpy change (Delta H), and entropy change (Delta S) for BSA + complexes 1 and 2 systems have been calculated by the van't Hoff equation at three different temperatures (293.2, 303.2, and 310.2 K). The distance between the BSA and these complexes has been determined using fluorescence resonance energy transfer (FRET). Conformational changes of BSA have been observed using the synchronous fluorescence technique. In addition, in vitro cytotoxicities of these complexes on tumor cell lines (Caco-2, A549, and MCF-7) and healthy cells (BEAS-2B) have been examined. The antimicrobial activity of the complexes has also been tested on certain bacteria cells. The effect of mono and dimeric in the above complexes is presented and discussed. New copper(II) complexes-dimeric-[Cu(nphen)(gly)(H2O)](+) (1) and [Cu(dmphen)(gly) (NO3)(H2O)] (2) (nphen = 5-nitro-1,10-phenanthroline, dmphen = 4,7-dimethyl-1,10-phenanthroline and gly = glycine)-have been synthesized and characterized by CHN analysis, single-crystal X-ray diffraction techniques, FTIR and EPR spectroscopy. They have been tested for their in vitro DNA/BSA interactions by the spectroscopic methods. These complexes exhibited higher cytotoxic and antimicrobial activities. Complex 1 shows better DNA / BSA interactions in comparison to complex 2.

New 5,5-diethylbarbiturate (barb) complexes of Ni(II), Cu(II) and Zn(II) with 1,10-phenanthroline (phen) and 2,2'-dipyridylamine (dpya), namely [Ni(phen-kappa N,N')(3)]Cl(barb)center dot 7H(2)O (1), [Cu(barb-kappa N)(barb-kappa N-2,O)(phen-kappa N,N')]center dot H2O (2), [Cu(barb-kappa N)(2)(phen-kappa N,N')] (2a), [Zn(barb-kappa N)(2)(phen-kappa N,N')]center dot H2O (3), [Ni(barb-kappa N-2,O) (dpya-kappa N,N')(2)]Cl center dot 2H(2)O (4), [Cu(barb-kappa N-2,O)(2)(dpya-kappa N,N')]center dot 2H(2)O (5) and [Zn(barb-kappa N)(2)(dpya-kappa N,N')] (6), were synthesized and characterized by elemental analysis, UV-vis, FT-IR and ESI-MS. The structures of the complexes were determined by X-ray crystallography. Notably, 3 and 6 were fluorescent in MeOH : H2O at rt. The interaction of the complexes with fish sperm (FS) DNA and bovine serum albumin (BSA) was investigated in detail by various techniques. The complexes exhibited groove binding along with a partial intercalative interaction with DNA, while the hydrogen bonding and hydrophobic interactions played a major role in binding to BSA. It is noteworthy that 2 exhibited the highest affinity towards DNA and BSA. Enzyme inhibition assay showed that 1-4 show a preference for both A/T and G/C rich sequences in pUC19 DNA, while 5 and 6 display a binding specificity to the G/C and A/T rich regions, respectively. These findings were further supported by molecular docking. The cellular uptake studies suggested that 2 was deposited mostly in the membrane fraction of the cells. Among the present complexes, 2 exhibited a very strong cytotoxic effect on A549, MCF-7, HT-29 and DU-145 cancer cells, being more potent than cisplatin. Moreover, 2 induces cell death through the apoptotic mode obtained by flow cytometry.

A new bis-phenanthroline dicopper(II) complex has been synthesized and characterized by elemental analysis and spectroscopic methods. The molecular structure of the dinuclear Cu(II) complex [Cu2(?-CH 3COO)(?-H2O)(?-OH)(phen)2]2+ (phen = 1,10-phenanthroline) (1) was determined by single crystal X-ray diffraction technique. The coordination environment around each Cu(II) ion in complex 1 can be described as slightly distorted square pyramidal geometry. The distance between the Cu?Cu centers in the complex is found to be 2.987 �. The electronic, redox, phosphate hydrolysis, DNA binding and DNA cleavage have been studied. The antiproliferative effect of complex 1 was confirmed by the lactate dehydrogenase (LDH) enzyme level in MCF-7 cancer cell lysate and content media. The dicopper(II) complex inhibited the LDH enzyme as well as the growth of the human breast cancer MCF7 cell line at an IC 50 value of 0.011 ?g ml-1. The results strongly suggest that complex 1 is a good cancer therapeutic agent. Electrochemical studies of complex 1 showed an irreversible, followed by a quasi-reversible, one electron reduction processes between -0.20 to -0.8 V. Michaelis-Menten kinetic parameters for the hydrolysis of 4-nitrophenyl phosphate by complex 1 are kcat = 3.56 � 10-2 s-1 and KM = 4.3 � 10-2 M. Complex 1 shows good binding propensity to calf thymus DNA, with a binding constant value of 1.3 (�0.13) � 105 M-1 (s = 2.1). The size of the binding site and viscosity data suggest a DNA intercalative binding nature of the complex. Complex 1 shows efficient hydrolytic cleavage of supercoiled pBR322-DNA in the dark and in the absence of any external reagents, as demonstrated by the T4 ligase experiment. The pseudo-Michaelis-Menten kinetic parameters for DNA hydrolysis by complex 1 are kcat = 1.27 � 0.4 h-1 and KM = 7.7 � 10-2 M. � 2011 The Royal Society of Chemistry.