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Special Issue "Metal Complexes of Biological Ligands"

A special issue of Molecules (ISSN 1420-3049). This special issue belongs to the section "Organometallic Chemistry".

Deadline for manuscript submissions: closed (31 July 2018)

Special Issue Editor

Guest Editor
Prof. Dr. Wolfgang Beck

Department Chemie, Ludwig-Maximilians-Universität, München, Germany
Website | E-Mail
Interests: metal complexes with biologically important ligands; metal complexes with pseudohalide ligands; organometallic chemistry; organometallic Lewis acids: hydrocarbon bridged metal complexes; metal complexes of dyes; nitrosyl metal complexes

Special Issue Information

Dear Colleagues,

The coordination chemistry of biometals, e.g., Cr, Mn, Fe, Co, Ni, Cu, Zn, and Mo, with biological ligands, comprises an important part in the field of the rapidly-growing Bioinorganic Chemistry. Metal complexes with bioligands play a decisive role for the understanding of biochemical processes. New results on metal complexes with essential biological ligands, amino acids, peptides, proteins, sugars, polysaccharides, nucleobases, nucleosides, DNA, RNA and natural macrocycles (e.g., porphyrins, haemes) find great interest, from structural, biochemical and even medicinal aspects. Other relevant bioligands are naturally-occurring heterocycles, sulfur ligands, phosphates, natural products, e.g., alkaloids, flavine, and vitamins. Metal complexes with nitrogen, carbon monoxide, nitrogen monoxide, oxygen, and carbon dioxide may exhibit biological aspects. For this Special Issue, bio-inspired model complexes are also highly welcome.

Researchers in this field are kindly invited to submit their results to this Special Issue. We are looking forward to receiving many fascinating reports.

Prof. Dr. Wolfgang Beck
Guest Editor

Manuscript Submission Information

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Keywords

  • metal complexes
  • bioligands
  • ligands in nature
  • biometals
  • coordination chemistry
  • organometallic chemistry

Published Papers (12 papers)

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Research

Open AccessArticle Peroxidative Oxidation of Alkanes and Alcohols under Mild Conditions by Di- and Tetranuclear Copper (II) Complexes of Bis (2-Hydroxybenzylidene) Isophthalohydrazide
Molecules 2018, 23(10), 2699; https://doi.org/10.3390/molecules23102699
Received: 27 September 2018 / Revised: 13 October 2018 / Accepted: 15 October 2018 / Published: 19 October 2018
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Abstract
Bis(2-hydroxybenzylidene)isophthalohydrazide (H4L) has been used to synthesize the dinuclear [Cu2(1κNO2:2κN′O′2-H2L)(NO3)2(H2O)2] (1) and the tetranuclear [Cu4(μ-1κNO2:2κN
[...] Read more.
Bis(2-hydroxybenzylidene)isophthalohydrazide (H4L) has been used to synthesize the dinuclear [Cu2(1κNO2:2κN′O′2-H2L)(NO3)2(H2O)2] (1) and the tetranuclear [Cu4(μ-1κNO2:2κN′O2-H2L)2(μ-NO3)2(H2O)4]·2C2H5OH (2) complexes. The solvent plays an important role in determining the ligand behaviour in the syntheses of the complexes. An ethanol-acetonitrile mixture of solvents favours partials enolization in the case of 2. Both complexes have been characterized by elemental analysis, infrared radiation (IR), single crystal X-ray crystallography and electrochemical methods. The variable temperature magnetic susceptibility measurements of 2 show strong antiferromagnetic coupling between the central nitrato-bridged Cu (II) ions. The catalytic activity of both 1 and 2 has been screened toward the solvent-free microwave-assisted oxidation of alcohols and the peroxidative oxidation of alkanes under mild conditions. Complex 1 exhibits the highest activity for both oxidation reactions, leading selectively to a maximum product yield of 99% (for the 1-phenylethanol oxidation after 1 h without any additive) and 13% (for the cyclohexane oxidation to cyclohexyl hydroperoxide, cyclohexanol and cyclohexanone after 3 h). Full article
(This article belongs to the Special Issue Metal Complexes of Biological Ligands)
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Open AccessCommunication Polypyridyl Zinc(II)-Indomethacin Complexes with Potent Anti-Breast Cancer Stem Cell Activity
Molecules 2018, 23(9), 2253; https://doi.org/10.3390/molecules23092253
Received: 17 August 2018 / Revised: 27 August 2018 / Accepted: 31 August 2018 / Published: 4 September 2018
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Abstract
Cancer stem cells (CSCs) are thought of as a clinically pertinent subpopulation of tumors, partly responsible for cancer relapse and metastasis. Research programs aimed at discovering anti-CSC agents have largely focused on biologics and purely organic molecules. Recently, we showed that a family
[...] Read more.
Cancer stem cells (CSCs) are thought of as a clinically pertinent subpopulation of tumors, partly responsible for cancer relapse and metastasis. Research programs aimed at discovering anti-CSC agents have largely focused on biologics and purely organic molecules. Recently, we showed that a family of redox-active copper(II) complexes with phenanthroline-based ligands and nonsteroidal anti-inflammatory drugs (NSAIDs) such as indomethacin, are capable of potently and selectively killing breast CSCs. Herein we present analogous redox-inactive, zinc(II)-phenanthroline-indomethacin complexes with the ability to kill breast CSCs and bulk breast cancer cells with equal potency (in the submicro- or micromolar range). A single dose of the zinc(II) complexes could theoretically be administered to eliminate whole tumor populations. Excitingly, some of the zinc(II) complexes decrease the growth and viability of mammospheres to a comparable or higher degree than salinomycin, a compound known to effectively kill breast CSCs. As far as we are aware this is the first report to examine the anti-breast CSC activity of zinc(II)-containing compounds. Full article
(This article belongs to the Special Issue Metal Complexes of Biological Ligands)
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Open AccessFeature PaperArticle Synthesis and Cytotoxicity Studies of Novel NHC*-Gold(I) Complexes Derived from Lepidiline A
Molecules 2018, 23(8), 2031; https://doi.org/10.3390/molecules23082031
Received: 3 August 2018 / Revised: 7 August 2018 / Accepted: 13 August 2018 / Published: 14 August 2018
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Abstract
Ten novel N-heterocyclic carbene gold(I) complexes derived from lepidiline A (1,3-dibenzyl-4,5-dimethylimidazolium chloride) are reported here with full characterisation and biological testing. (1,3-Dibenzyl-4,5-diphenylimidazol-2-ylidene)gold(I) chloride (NHC*-AuCl) (1) was modified by substituting the chloride for the following: cyanide (2), dithiocarbamates (
[...] Read more.
Ten novel N-heterocyclic carbene gold(I) complexes derived from lepidiline A (1,3-dibenzyl-4,5-dimethylimidazolium chloride) are reported here with full characterisation and biological testing. (1,3-Dibenzyl-4,5-diphenylimidazol-2-ylidene)gold(I) chloride (NHC*-AuCl) (1) was modified by substituting the chloride for the following: cyanide (2), dithiocarbamates (35), p-mercaptobenzoate derivatives (1214) and N-acetyl-l-cysteine derivatives (1517). All complexes were synthesised in good yields of 57–78%. Complexes 2, 12, 13, and 14 were further characterised by X-ray crystallography. Initial evaluation of the biological activity was conducted on all ten complexes against the multidrug resistant MCF-7topo breast cancer, HCT-116wt, and p53 knockout mutant HCT-116−/− colon carcinoma cell lines. Across the three cell lines tested, mainly single-digit micromolar IC50 values were observed. Nanomolar activity was exhibited on the MCF-7topo cell line with 3 displaying an IC50 of 0.28 μM ± 0.03 μM. Complexes incorporating a Au–S bond resulted in higher cytotoxic activity when compared to complexes 1 and 2. Theoretical calculations, carried out at the MN15/6–311++G(2df,p) computational level, show that NHC* is the more favourable ligand for Au(I)-Cl when compared to PPh3. Full article
(This article belongs to the Special Issue Metal Complexes of Biological Ligands)
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Open AccessArticle Effects of a Ruthenium Schiff Base Complex on Glucose Homeostasis in Diet-Induced Pre-Diabetic Rats
Molecules 2018, 23(7), 1721; https://doi.org/10.3390/molecules23071721
Received: 7 June 2018 / Revised: 11 July 2018 / Accepted: 11 July 2018 / Published: 14 July 2018
Cited by 1 | PDF Full-text (1678 KB) | HTML Full-text | XML Full-text
Abstract
Pre-diabetes is a condition that precedes type 2 diabetes mellitus (T2DM) that is characterised by elevated glycated haemoglobin (HbA1c). The management of pre-diabetes includes the combination of dietary and pharmacological interventions to increase insulin sensitivity. However, poor patient compliance has been reported with
[...] Read more.
Pre-diabetes is a condition that precedes type 2 diabetes mellitus (T2DM) that is characterised by elevated glycated haemoglobin (HbA1c). The management of pre-diabetes includes the combination of dietary and pharmacological interventions to increase insulin sensitivity. However, poor patient compliance has been reported with regard to dietary interventions, therefore, new alternative drugs are required that can be effective even without the dietary intervention. In our laboratory, we have synthesised a novel ruthenium complex that has been shown to have elevated biological activity. This study investigated the effects of this complex in both the presence and absence of dietary intervention on glucose handling in a diet-induced pre-diabetes rat model. Pre-diabetic animals were randomly assigned to respective treatment groups. The ruthenium complex was administered to pre-diabetic rats once a day every third day for 12 weeks. The administration of the ruthenium complex resulted in reduced fasting blood glucose, food intake, and body weight gain which was associated with decreased plasma ghrelin, insulin, and HbA1c levels in both the presence and absence of dietary intervention. The administration of the ruthenium complex ameliorated glycaemic control and insulin sensitivity in pre-diabetic rats. The results of this study warrant further investigations as this compound could potentially be able to re-sensitize insulin resistant cells and reduce the incidence of T2DM. Full article
(This article belongs to the Special Issue Metal Complexes of Biological Ligands)
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Open AccessArticle Spectroscopical Investigations on the Redox Chemistry of [FeFe]-Hydrogenases in the Presence of Carbon Monoxide
Molecules 2018, 23(7), 1669; https://doi.org/10.3390/molecules23071669
Received: 19 June 2018 / Revised: 4 July 2018 / Accepted: 6 July 2018 / Published: 9 July 2018
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Abstract
[FeFe]-hydrogenases efficiently catalyzes hydrogen conversion at a unique [4Fe–4S]-[FeFe] cofactor, the so-called H-cluster. The catalytic reaction occurs at the diiron site, while the [4Fe–4S] cluster functions as a redox shuttle. In the oxidized resting state (Hox), the iron ions of the diiron site
[...] Read more.
[FeFe]-hydrogenases efficiently catalyzes hydrogen conversion at a unique [4Fe–4S]-[FeFe] cofactor, the so-called H-cluster. The catalytic reaction occurs at the diiron site, while the [4Fe–4S] cluster functions as a redox shuttle. In the oxidized resting state (Hox), the iron ions of the diiron site bind one cyanide (CN) and carbon monoxide (CO) ligand each and a third carbonyl can be found in the Fe–Fe bridging position (µCO). In the presence of exogenous CO, A fourth CO ligand binds at the diiron site to form the oxidized, CO-inhibited H-cluster (Hox-CO). We investigated the reduced, CO-inhibited H-cluster (Hred´-CO) in this work. The stretching vibrations of the diatomic ligands were monitored by attenuated total reflection Fourier-transform infrared spectroscopy (ATR FTIR). Density functional theory (DFT) at the TPSSh/TZVP level was employed to analyze the cofactor geometry, as well as the redox and protonation state of the H-cluster. Selective 13CO isotope editing, spectro-electrochemistry, and correlation analysis of IR data identified a one-electron reduced, protonated [4Fe–4S] cluster and an apical CN ligand at the diiron site in Hred´-CO. The reduced, CO-inhibited H-cluster forms independently of the sequence of CO binding and cofactor reduction, which implies that the ligand rearrangement at the diiron site upon CO inhibition is independent of the redox and protonation state of the [4Fe–4S] cluster. The relation of coordination dynamics to cofactor redox and protonation changes in hydrogen conversion catalysis and inhibition is discussed. Full article
(This article belongs to the Special Issue Metal Complexes of Biological Ligands)
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Open AccessArticle Cu(II) Complexes of 4-[(1E)-N-{2-[(Z)-Benzylidene-amino]ethyl}ethanimidoyl]benzene-1,3-diol Schiff Base: Synthesis, Spectroscopic, In-Vitro Antioxidant, Antifungal and Antibacterial Studies
Molecules 2018, 23(7), 1581; https://doi.org/10.3390/molecules23071581
Received: 2 May 2018 / Revised: 24 May 2018 / Accepted: 30 May 2018 / Published: 29 June 2018
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Abstract
The current study reports the synthesis of copper complexes of a tridentate Schiff base ligand. The compounds of the type [Cu(L)X]∙n(H2O) (where L = tridentate ONN Schiff base ligand, X = Cl, Br, SCN, NO
[...] Read more.
The current study reports the synthesis of copper complexes of a tridentate Schiff base ligand. The compounds of the type [Cu(L)X]∙n(H2O) (where L = tridentate ONN Schiff base ligand, X = Cl, Br, SCN, NO3, CH3COO), were characterized on the basis of elemental analyses, FT-IR, UV-vis, molar conductance, 1H-NMR, XRD and thermal analyses. The spectra revealed that the Schiff base ligand acts as a tridentate ligand through two azomethine nitrogen atoms and a phenolic oxygen atom. The molar conductance measurements of the complexes in DMF correspond to non-electrolytic nature. TGA and DTA studies results gave insight into the dehydration, thermal stability, and thermal decomposition. Square-planar geometry has been assigned to the prepared complexes as indicated by the electronic spectral measurements. Cu(II) compounds showed antiradical potential against DPPH and ABTS radicals. The antimicrobial potential of the Schiff base ligand and its Cu(II) complexes were evaluated by the rapid p-iodonitrotetrazolium chloride (INT) colorimetric assay against some selected bacteria strains: Staphylococcus aureus and Enterococcus faecalis (Gram +ve); Klebsiella pneumoniae and Pseudomonas aeruginosa (Gram −ve), and fungi (Candida albicans and Cryptococcus neoformans). The compounds showed a broad spectrum of antibacterial and antifungal activities, with MIC values ranging from 48.83 to 3125 μg/mL. Full article
(This article belongs to the Special Issue Metal Complexes of Biological Ligands)
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Open AccessArticle Detection and Identification of Estrogen Based on Surface-Enhanced Resonance Raman Scattering (SERRS)
Molecules 2018, 23(6), 1330; https://doi.org/10.3390/molecules23061330
Received: 25 April 2018 / Revised: 28 May 2018 / Accepted: 31 May 2018 / Published: 1 June 2018
Cited by 1 | PDF Full-text (14719 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
Many studies have shown that it is important to consider the harmful effects of phenolic hormones on the human body. Traditional UV detection has many limitations, so there is a need to develop new detection methods. We demonstrated a simple and rapid surface-enhanced
[...] Read more.
Many studies have shown that it is important to consider the harmful effects of phenolic hormones on the human body. Traditional UV detection has many limitations, so there is a need to develop new detection methods. We demonstrated a simple and rapid surface-enhanced resonance Raman scattering (SERRS) based detection method of trace amounts of phenolic estrogen. As a result of the coupling reaction, there is the formation of strong SERRS activity of azo compound. Therefore, the detection limits are as low as 0.2 × 10−4 for estrone (E1), estriol (E3), and bisphenol A (BPA). This method is universal because each SERRS fingerprint of the azo dyes a specific hormone. The use of this method is applicable for the testing of phenolic hormones through coupling reactions, and the investigation of other phenolic molecules. Therefore, this new method can be used for efficient detection. Full article
(This article belongs to the Special Issue Metal Complexes of Biological Ligands)
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Open AccessCommunication Dicyanamide Bridged Cu(II)36-Metallacrown-6 Complex with 1,4,7-Triisopropyl-1,4,7-Triazacyclononane and Binding Properties with DNA
Molecules 2018, 23(6), 1269; https://doi.org/10.3390/molecules23061269
Received: 15 May 2018 / Revised: 21 May 2018 / Accepted: 22 May 2018 / Published: 25 May 2018
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Abstract
A novel 36-metallacrown-6 complex [CuL(N(CN)2)(PF6)]6∙0.5H2O 1 was achieved using a tridendate ligand, 1,4,7-triisopropyl-1,4,7-triazacyclononane (L), and a flexible ligand, dicyanamide in MeOH. The μ1,5 bridging models of the dicyanamide ligand linked the macrocycle to form
[...] Read more.
A novel 36-metallacrown-6 complex [CuL(N(CN)2)(PF6)]6∙0.5H2O 1 was achieved using a tridendate ligand, 1,4,7-triisopropyl-1,4,7-triazacyclononane (L), and a flexible ligand, dicyanamide in MeOH. The μ1,5 bridging models of the dicyanamide ligand linked the macrocycle to form in a specific size with the chair conformation. The anion was important to form this 36-metallacrown-6 complex, as change was obtained with the larger anion BPh4, binuclear copper compound 2. The magnetic property indicates that slightly ferromagnetic interactions resulted from a superexchange mechanism. DNA binding properties were also studied. UV and fluorescence spectra showed that complex 1 could bind with DNA. Full article
(This article belongs to the Special Issue Metal Complexes of Biological Ligands)
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Open AccessArticle Synthesis, Spectroscopic, and Biological Studies of Mixed Ligand Complexes of Gemifloxacin and Glycine with Zn(II), Sn(II), and Ce(III)
Molecules 2018, 23(5), 1182; https://doi.org/10.3390/molecules23051182
Received: 30 April 2018 / Revised: 11 May 2018 / Accepted: 11 May 2018 / Published: 15 May 2018
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Abstract
Three novel mixed ligand metal complexes have been synthesized by the reaction of Zn(II), Sn(II), and Ce(III) with gemifloxacin (GMFX) in the presence of glycine (Gly) (1:1:1 molar ratio). The coordination possibility of the two ligands toward metal ions has been proposed in
[...] Read more.
Three novel mixed ligand metal complexes have been synthesized by the reaction of Zn(II), Sn(II), and Ce(III) with gemifloxacin (GMFX) in the presence of glycine (Gly) (1:1:1 molar ratio). The coordination possibility of the two ligands toward metal ions has been proposed in the light of elemental analysis, molar conductance, spectral infrared (IR), ultraviolet-visible (UV-Vis) and proton-nuclear magnetic resonance (1H NMR), and magnetic studies. Results suggest that GMFX and Gly interact with the metal ions as bidentate ligands. Electronic and magnetic data proposed the octahedral structure for all complexes under investigation. Antibacterial screening of the compounds was carried out in vitro against two Gram-positive bacteria, Clavibacter michiganensis and Bacillus megaterium, and two Gram-negative bacteria, Escherichia coli and Xanthomonas campestris. Antifungal activity was performed in vitro against Rhizoctonia solani, Sclerotinia sclerotiorum, Aspergillus niger, Botrytis cinerea, and Penicillium digitatum. The ligands and their complexes were also screened for their antioxidant activity. Results showed that some metal complexes showed more biological efficiency than the parent GMFX drug. Full article
(This article belongs to the Special Issue Metal Complexes of Biological Ligands)
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Open AccessArticle Synthesis and Fluorescence Properties of a New Heterotrinuclear Co(II)-Ce(III)Complex Constructed from a bis(salamo)-Type Tetraoxime Ligand
Molecules 2018, 23(4), 804; https://doi.org/10.3390/molecules23040804
Received: 27 February 2018 / Revised: 20 March 2018 / Accepted: 30 March 2018 / Published: 31 March 2018
Cited by 1 | PDF Full-text (27897 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
[Co2(L)Ce(OAc)3(CH3CH2OH)]·1.5CH3OH∙0.5CH2Cl2, a heterotrinuclear Co(II)-Ce(III) bis(salamo)-type complex with a symmetric bi(salamo)-type ligand H4L and an acyclic naphthalenediol moiety, was designed, synthesized and characterized by elemental analyses, FT-IR, UV-Vis
[...] Read more.
[Co2(L)Ce(OAc)3(CH3CH2OH)]·1.5CH3OH∙0.5CH2Cl2, a heterotrinuclear Co(II)-Ce(III) bis(salamo)-type complex with a symmetric bi(salamo)-type ligand H4L and an acyclic naphthalenediol moiety, was designed, synthesized and characterized by elemental analyses, FT-IR, UV-Vis and fluorescence spectroscopy and X-ray crystallography. The X-ray crystallographic investigation revealed the heterotrinuclear complex consisted of two Co(II) atoms, one Ce(III) atom, one (L)4‒ unit, three μ2-acetate ions, one coordinated ethanol molecule, one and half crystallization methanol molecule and half crystallization dichloromethane molecule. Two Co(II) atoms located in the N2O2 coordination spheres, are both hexacoordinated, with slightly distorted octahedral geometries. The Ce(III) atom is nine-coordinated and located in the O6 cavity possesses a single square antiprismatic geometry. In addition, supramolecular interactions exist in the Co(II)-Ce(III) complex. Two infinite 2D supramolecular structures are built via intermolecular O–H···O, C–H···O and C–H···π interactions, respectively. Full article
(This article belongs to the Special Issue Metal Complexes of Biological Ligands)
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Open AccessArticle Synthesis, Characterization, Crystal Structure, and DFT Study of a New Square Planar Cu(II) Complex Containing Bulky Adamantane Ligand
Molecules 2018, 23(3), 701; https://doi.org/10.3390/molecules23030701
Received: 26 February 2018 / Revised: 9 March 2018 / Accepted: 13 March 2018 / Published: 20 March 2018
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Abstract
A copper complex with square planar geometry, [(L)CuBr2] (1), (L = N′-(furan-2-ylmethylene)adamantne-1-carbohydrazide) has been synthesized and characterized by Fourier transfer infrared (FTIR) spectroscopy, elemental analysis, mass spectrometry, and single crystal X-ray diffraction. The crystal of 1 is solved
[...] Read more.
A copper complex with square planar geometry, [(L)CuBr2] (1), (L = N′-(furan-2-ylmethylene)adamantne-1-carbohydrazide) has been synthesized and characterized by Fourier transfer infrared (FTIR) spectroscopy, elemental analysis, mass spectrometry, and single crystal X-ray diffraction. The crystal of 1 is solved as monoclinic, space group P21/m with unit cell parameters: a = 10.8030(8), b = 6.6115(8), c = 12.1264(12) Å, β = 101.124(8)°, V = 849.84(15) Å3, Z = 2, and R1 = 0.0751 with wR2 = 0.1581 (I > 2 σ). The structure of 1 shows intramolecular hydrogen bonding between the N–H and the furan oxygen which stabilizes the configuration of the complex. Furthermore, inside the lattice there are other weak interactions between bromo ligands and the ligand L. DFT calculations where performed to study the stability of this geometry. Full article
(This article belongs to the Special Issue Metal Complexes of Biological Ligands)
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Open AccessArticle Ni(II) Complexes with Schiff Base Ligands: Preparation, Characterization, DNA/Protein Interaction and Cytotoxicity Studies
Molecules 2017, 22(10), 1772; https://doi.org/10.3390/molecules22101772
Received: 14 September 2017 / Accepted: 16 October 2017 / Published: 24 October 2017
Cited by 6 | PDF Full-text (5276 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
In this study, two Ni(II) complexes, namely [Ni(HL1)2(OAc)2] (1) and [Ni(L2)2] (2) (where HL1 and HL2 are (E)-1-((1-(2-hydroxyethyl)-1H-pyrazol-5-ylimino)methyl)-naphthalen-2-ol) and (E)-ethyl-5-((2-hydroxynaphthalen-1-yl)methyleneamino)-1-methyl-1H-pyrazole-4-carboxylate, respectively), were synthesized and characterized
[...] Read more.
In this study, two Ni(II) complexes, namely [Ni(HL1)2(OAc)2] (1) and [Ni(L2)2] (2) (where HL1 and HL2 are (E)-1-((1-(2-hydroxyethyl)-1H-pyrazol-5-ylimino)methyl)-naphthalen-2-ol) and (E)-ethyl-5-((2-hydroxynaphthalen-1-yl)methyleneamino)-1-methyl-1H-pyrazole-4-carboxylate, respectively), were synthesized and characterized by X-ray crystallography, Electrospray Ionization Mass Spectrometry (ESI-MS), elemental analysis, and IR. Their uptake in biological macromolecules and cancer cells were preliminarily investigated through electronic absorption (UV-Vis), circular dichroism (CD) and fluorescence quenching measurements. Bovine serum albumin (BSA) interaction experiments were investigated by spectroscopy which showed that the complexes and ligands could quench the intrinsic fluorescence of BSA through an obvious static quenching process. The spectroscopic studies indicated that these complexes could bind to DNA via groove, non-covalent, and electrostatic interactions. Furthermore, in vitro methyl thiazolyl tetrazolium (MTT) assays and Annexin V/PI flow cytometry experiments were performed to assess the antitumor capacity of the complexes against eight cell lines. The results show that both of the complexes possess reasonable cytotoxicities. Full article
(This article belongs to the Special Issue Metal Complexes of Biological Ligands)
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