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Liu HJ, Yi R, Chen DM, Huang C, Zhu BX. Self-Assembly by Tridentate or Bidentate Ligand: Synthesis and Vapor Adsorption Properties of Cu(II), Zn(II), Hg(II) and Cd(II) Complexes Derived from a Bis(pyridylhydrazone) Compound. Molecules 2020; 26:molecules26010109. [PMID: 33383694 PMCID: PMC7795747 DOI: 10.3390/molecules26010109] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2020] [Revised: 12/11/2020] [Accepted: 12/22/2020] [Indexed: 02/06/2023] Open
Abstract
Four complexes, [Cu4L2(OCH3)2(CH3OH)2]·2H2O (1), [Zn2L2Cl4]·2H2O·2CH3OH (2), [Hg2L2Br4]·4CH3OH (3), and {[CdL2Cl2]·4H2O·4CH3OH}n (4), have been synthesized and characterized from a bis(pyridylhydrazone) ligand (L) with copper(II), zinc(II), mercury(II) or cadmium(II), respectively. Complex 1 exists as a centrosymmetric tetranuclear dimer with L as deprotonated tridentate ligand. Complexes 2 and 3 exist as centrosymmetric metallamacrocycles with L as bidentate ligand. Complex 4 exists as a 1D looped-chain coordination polymer. The thermal stabilities and vapor adsorption properties of the four complexes were investigated as well.
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2
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Risi G, Becker M, Housecroft CE, Constable EC. Are Alkynyl Spacers in Ancillary Ligands in Heteroleptic Bis(diimine)copper(I) Dyes Beneficial for Dye Performance in Dye-Sensitized Solar Cells? Molecules 2020; 25:E1528. [PMID: 32230862 PMCID: PMC7180879 DOI: 10.3390/molecules25071528] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2020] [Revised: 03/22/2020] [Accepted: 03/26/2020] [Indexed: 11/16/2022] Open
Abstract
The syntheses of 4,4'-bis(4-dimethylaminophenyl)-6,6'-dimethyl-2,2'-bipyridine (1), 4,4'-bis(4-dimethylaminophenylethynyl)-6,6'-dimethyl-2,2'-bipyridine (2), 4,4'-bis(4-diphenylaminophenyl)-6,6'-dimethyl-2,2'-bipyridine (3), and 4,4'-bis(4-diphenylaminophenylethynyl)-6,6'-dimethyl-2,2'-bipyridine (4) are reported along with the preparations and characterisations of their homoleptic copper(I) complexes [CuL2][PF6] (L = 1-4). The solution absorption spectra of the complexes exhibit ligand-centred absorptions in addition to absorptions in the visible region assigned to a combination of intra-ligand and metal-to-ligand charge-transfer. Heteroleptic [Cu(5)(Lancillary)]+ dyes in which 5 is the anchoring ligand ((6,6'-dimethyl-[2,2'-bipyridine]-4,4'-diyl)bis(4,1-phenylene))bis(phosphonic acid) and Lancillary = 1-4 have been assembled on fluorine-doped tin oxide (FTO)-TiO2 electrodes in dye-sensitized solar cells (DSCs). Performance parameters and external quantum efficiency (EQE) spectra of the DSCs (four fully-masked cells for each dye) reveal that the best performing dyes are [Cu(5)(1)]+ and [Cu(5)(3)]+. The alkynyl spacers are not beneficial, leading to a decrease in the short-circuit current density (JSC), confirmed by lower values of EQEmax. Addition of a co-absorbent (n-decylphosphonic acid) to [Cu(5)(1)]+ lead to no significant enhancement of performance for DSCs sensitized with [Cu(5)(1)]+. Electrochemical impedance spectroscopy (EIS) has been used to investigate the interfaces in DSCs; the analysis shows that more favourable electron injection into TiO2 is observed for sensitizers without the alkynyl spacer and confirms higher JSC values for [Cu(5)(1)]+.
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Affiliation(s)
| | | | | | - Edwin C. Constable
- Department of Chemistry, University of Basel, BPR 1096, Mattenstrasse 24a, CH-4058 Basel, Switzerland; (G.R.); (M.B.); (C.E.H.)
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Solea AB, Cornu I, Deneva V, Crochet A, Fromm KM, Antonov L, Allemann C, Mamula O. Tautomerism and Self-Association in the Solution of New Pinene-Bipyridine and Pinene-Phenanthroline Derivatives. Molecules 2020; 25:E298. [PMID: 31940835 PMCID: PMC7024227 DOI: 10.3390/molecules25020298] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2019] [Revised: 12/16/2019] [Accepted: 12/27/2019] [Indexed: 11/16/2022] Open
Abstract
Two novel pinene-type ligands have been synthesized and their tautomeric and self-associating behavior studied in solution and in the solid state. The first ligand, an acetylated derivative of 5,6-pinene-bipyridine, displays keto-enol tautomerism in solution. This tautomeric equilibrium was studied by NMR and UV-Vis spectroscopy in various solvents, and the results were compared with the ones obtained through DFT calculations. The second ligand was obtained by an unusual oxidation of the phenanthroline unit of a pinene-phenanthroline derivative. This compound exists as a single tautomer in solution and aggregates both in solution (as observed by NMR) and in the solid state through H-bonding as observed by X-ray structure determination and confirmed by DFT studies.
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Affiliation(s)
- Atena B. Solea
- Haute Ecole d’Ingénierie et d’Architecture Fribourg, HES-SO University of Applied Sciences of Western Switzerland, Pérolles 80, CH-1705 Fribourg, Switzerland; (A.B.S.); (I.C.); (A.C.); (C.A.)
- Department of Chemistry, University of Fribourg, Chemin du Musée 9, CH-1700 Fribourg, Switzerland;
| | - Ivan Cornu
- Haute Ecole d’Ingénierie et d’Architecture Fribourg, HES-SO University of Applied Sciences of Western Switzerland, Pérolles 80, CH-1705 Fribourg, Switzerland; (A.B.S.); (I.C.); (A.C.); (C.A.)
| | - Vera Deneva
- Bulgarian Academy of Sciences, Institute of Organic Chemistry with Centre of Phytochemistry, Acad. G. Bonchev street, bl. 9, 1113 Sofia, Bulgaria; (V.D.); (L.A.)
| | - Aurelien Crochet
- Haute Ecole d’Ingénierie et d’Architecture Fribourg, HES-SO University of Applied Sciences of Western Switzerland, Pérolles 80, CH-1705 Fribourg, Switzerland; (A.B.S.); (I.C.); (A.C.); (C.A.)
| | - Katharina M. Fromm
- Department of Chemistry, University of Fribourg, Chemin du Musée 9, CH-1700 Fribourg, Switzerland;
| | - Liudmil Antonov
- Bulgarian Academy of Sciences, Institute of Organic Chemistry with Centre of Phytochemistry, Acad. G. Bonchev street, bl. 9, 1113 Sofia, Bulgaria; (V.D.); (L.A.)
| | - Christophe Allemann
- Haute Ecole d’Ingénierie et d’Architecture Fribourg, HES-SO University of Applied Sciences of Western Switzerland, Pérolles 80, CH-1705 Fribourg, Switzerland; (A.B.S.); (I.C.); (A.C.); (C.A.)
| | - Olimpia Mamula
- Haute Ecole d’Ingénierie et d’Architecture Fribourg, HES-SO University of Applied Sciences of Western Switzerland, Pérolles 80, CH-1705 Fribourg, Switzerland; (A.B.S.); (I.C.); (A.C.); (C.A.)
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4
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Hashem SG, Elsaady MM, Afify HG, Omer WE, Youssef AO, El-Kemary M, Attia MS. Determination of uric acid in serum using an optical sensor based on binuclear Pd(II) 2-pyrazinecarboxamide-bipyridine doped in a sol gel matrix. Talanta 2019; 199:89-96. [PMID: 30952321 DOI: 10.1016/j.talanta.2019.02.056] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2018] [Revised: 02/10/2019] [Accepted: 02/12/2019] [Indexed: 01/23/2023]
Abstract
A new highly green luminescent binuclear palladium 2-pyrazinecarboxamide-bipyridine complex [Pd(pyc)(bpy)] was prepared and characterized. The binuclear Pd(pyc)(bpy) complex doped in sol-gel matrix has a strong luminescence intensity at 547 nm with λex = 330 nm in water The method depends on the quenching of the luminescence intensity of the binuclear Pd(pyc)(bpy) complex at 547 nm by different concentrations of uric acid. The remarkable quenching of the luminescence intensity of the binuclear Pd(pyc)(bpy) complex, doped in a sol-gel matrix, by uric acid was successfully used for the determination of uric acid in serum samples of patients with hypouricemia disease. The calibration plot was achieved over the concentration 3.9 × 10-9 to 1.2 × 10-4 mol L-1uric acid with a correlation coefficient of 0.9 and a detection limit of 1.8 × 10-10 mol L-1. The method was used satisfactorily for the assessment of the uric acid in a number of serum samples collected from various patients with Hypouricemia disease.
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Affiliation(s)
- S G Hashem
- Ain Shams University, Department of chemistry, Faculty of Science, Abbassia, 11566 Cairo, Egypt
| | - M M Elsaady
- Ain Shams University, Department of chemistry, Faculty of Science, Abbassia, 11566 Cairo, Egypt
| | - H G Afify
- Ain Shams University, Department of chemistry, Faculty of Science, Abbassia, 11566 Cairo, Egypt
| | - W E Omer
- Institute of Nanoscience and Nanotechnology, Kafrelsheikh University, Egypt
| | - A O Youssef
- Ain Shams University, Department of chemistry, Faculty of Science, Abbassia, 11566 Cairo, Egypt
| | - Maged El-Kemary
- Institute of Nanoscience and Nanotechnology, Kafrelsheikh University, Egypt
| | - M S Attia
- Ain Shams University, Department of chemistry, Faculty of Science, Abbassia, 11566 Cairo, Egypt.
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5
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Kumar M, Kumar G, Mogha NK, Jain R, Hussain F, Masram DT. Structure, DNA/proteins binding, docking and cytotoxicity studies of copper(II) complexes with the first quinolone drug nalidixic acid and 2,2'‑dipyridylamine. Spectrochim Acta A Mol Biomol Spectrosc 2019; 212:94-104. [PMID: 30616168 DOI: 10.1016/j.saa.2018.12.045] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2018] [Revised: 12/18/2018] [Accepted: 12/22/2018] [Indexed: 06/09/2023]
Abstract
This work presents the synthesis, structural characterization and biological affinity of the newly synthesized copper(II) complexes with the first antibacterial quinolone drug nalidixic acid (nal) or N-donor ligand 2,2'‑dipyridylamine (bipyam). [Cu(II)(nal)(bipyam)Cl], (2) reveals a distorted square pyramidal based geometry in Cu(II) atom confirmed by X-ray crystallography technique. The theoretical stabilities and optimized structures of the complex were obtained from DFT calculations. The ability of the complexes to bind with calf thymus DNA (CT DNA) were investigated by electronic absorption, fluorescence, circular dichroism, and viscosity measurements techniques. The experimental results reveal that the complexes strongly interact with CT DNA via intercalative mode but complex 2 exhibits the highest affinity giving Kb=3.91±0.13×106, M-1. The fluorescence spectroscopy measurements show that both complexes have the superior ability to the replacement of EtBr from DNA-bound EtBr solution and bind to DNA through intercalative mode. Both complex also shows the superior affinity towards proteins with comparatively high binding constant values which have been further revealed by fluorescence spectroscopy measurements. Molecular docking analysis indicates that the interaction of the complexes and proteins are stabilized by hydrogen bonding and hydrophobic interaction. Furthermore, the results of in vitro cytotoxicity reveal that the complex 2 has excellent cytotoxicity than 1 against human breast cancer cell lines (MCF-7).
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Affiliation(s)
- Manish Kumar
- Department of Chemistry, University of Delhi, Delhi 110007, India
| | - Gyanendra Kumar
- Department of Chemistry, University of Delhi, Delhi 110007, India
| | | | - Ritu Jain
- Department of Chemistry, University of Delhi, Delhi 110007, India
| | - Firasat Hussain
- Department of Chemistry, University of Delhi, Delhi 110007, India
| | - Dhanraj T Masram
- Department of Chemistry, University of Delhi, Delhi 110007, India.
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6
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Zhang W, Yao D, Wei Y, Tang J, Bian HD, Huang FP, Liang H. Synthesis, characterization, DNA/protein interaction and cytotoxicity studies of Cu(II) and Co(II) complexes derived from dipyridyl triazole ligands. Spectrochim Acta A Mol Biomol Spectrosc 2016; 163:28-44. [PMID: 27043870 DOI: 10.1016/j.saa.2016.03.010] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/20/2015] [Revised: 03/10/2016] [Accepted: 03/11/2016] [Indexed: 06/05/2023]
Abstract
Four different transition metal complexes containing dipyridyl triazole ligands, namely [Cu(abpt)2Cl2]·2H2O (1), [Cu(abpt)2(ClO4)2] (2), [Co2(abpt)2(H2O)2Cl2]·Cl2·4H2O (3) and [Co2(Hbpt)2(CH3OH)2(NO3)2] (4) have been designed, synthesized and further structurally characterized by X-ray crystallography, ESI-MS, elemental analysis, IR and Raman spectroscopy. In these complexes, the both ligands act as bidentate ligands with N, N donors. DNA binding interactions with calf thymus DNA (ct-DNA) of the ligand and its complexes 1~4 were investigated via electronic absorption, fluorescence quenching, circular dichroism and viscosity measurements as well as confocal Laser Raman spectroscopy. The results show these complexes are able to bind to DNA via the non-covalent mode i.e. intercalation and groove binding or electrostatic interactions. The interactions with bovine serum albumin (BSA) were also studied using UV-Vis and fluorescence spectroscopic methods which indicated that fluorescence quenching of BSA by these compounds was the presence of both static and dynamic quenching. Moreover, the in vitro cytotoxic effects of the complexes against four cell lines SK-OV-3, HL-7702, BEL7404 and NCI-H460 showed the necessity of the coordination action on the biological properties on the respective complex and that all four complexes exhibited substantial cytotoxic activity.
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Affiliation(s)
- Wei Zhang
- Key Laboratory for the Chemistry and Molecular Engineering of Medicinal Resources (Ministry of Education of China), School of Chemistry and Pharmacy, Guangxi Normal University, Guilin 541004, PR China
| | - Di Yao
- Key Laboratory for the Chemistry and Molecular Engineering of Medicinal Resources (Ministry of Education of China), School of Chemistry and Pharmacy, Guangxi Normal University, Guilin 541004, PR China.
| | - Yi Wei
- Key Laboratory for the Chemistry and Molecular Engineering of Medicinal Resources (Ministry of Education of China), School of Chemistry and Pharmacy, Guangxi Normal University, Guilin 541004, PR China
| | - Jie Tang
- Key Laboratory for the Chemistry and Molecular Engineering of Medicinal Resources (Ministry of Education of China), School of Chemistry and Pharmacy, Guangxi Normal University, Guilin 541004, PR China
| | - He-Dong Bian
- Key Laboratory for the Chemistry and Molecular Engineering of Medicinal Resources (Ministry of Education of China), School of Chemistry and Pharmacy, Guangxi Normal University, Guilin 541004, PR China; School of Chemistry and Chemical Engineering, Guangxi University for Nationalities, Key Laboratory of Chemistry and Engineering of Forest Products, Nanning 530008, PR China
| | - Fu-Ping Huang
- Key Laboratory for the Chemistry and Molecular Engineering of Medicinal Resources (Ministry of Education of China), School of Chemistry and Pharmacy, Guangxi Normal University, Guilin 541004, PR China.
| | - Hong Liang
- Key Laboratory for the Chemistry and Molecular Engineering of Medicinal Resources (Ministry of Education of China), School of Chemistry and Pharmacy, Guangxi Normal University, Guilin 541004, PR China
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Azhari SJ, Mlahi MR, Mostafa MM. Comparative studies between 4-allyl-, 4-phenyl- and 4-ethyl-1-(2-hydroxybenzoyl) thiosemicarbazides and the synthesis, characterization and DFT calculations of binary and ternary complexes derived from 4-ethyl (L(1)) and 2,2'-dipyridyl. Spectrochim Acta A Mol Biomol Spectrosc 2015; 150:949-958. [PMID: 26123512 DOI: 10.1016/j.saa.2015.06.056] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/28/2014] [Revised: 06/15/2015] [Accepted: 06/17/2015] [Indexed: 06/04/2023]
Abstract
The metal complexes of 4-ethyl-1-(2-hydroxybenzoyl) thiosemicarbazide (L(1)) with MCl2 (M=Co(2+), Cu(2+) and Zn(2+)) and Zn(Ac)2 in EtOH were synthesized and characterized using spectral (IR, (1)H-NMR, mass, UV-Visible), magnetic moment and thermal measurements. Binary and ternary complexes with the general formulae, [Cu(L(1)-H)2]·EtOH, [Co(L(1)-H)2], [Zn3(L(1)-H)(L(1))(Ac)5], [Cu2(L(2))2(L(1)-2H)2(H2O)2]·4H2O, [Co(L(2))(L(1)-2H)]·3H2O and [Zn2(L(2))(OH)(L(1)-3H)(H2O)]·1/2EtOH where L(2) is 2,2'-dipyridyl, have been suggested and characterized. The bond lengths, bond angles, chemical reactivates, energy components, binding energies and dipole moments for the isolated complexes were evaluated by DFT method from DMOL(3). Also, the MEP for L(1) is illustrated. The existence of the OH group in the Zn(2+) ternary complexes is confirmed by IR, mass and (1)H-NMR spectra. Biological activity for the L(1) and some its complexes was tested against DNA. Comparative studies between the ligation behavior and reactivity of our previous work derived from 4-phenyl- and 4-allyl-1-(2-hydroxybenzoyl) thiosemicarbazides have been investigated.
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Affiliation(s)
- Shaker J Azhari
- Chemistry Department, Faculty of Applied Sciences, Umm Al-Qura University, Saudi Arabia
| | - Mosaad R Mlahi
- Chemistry Department, Faculty of Science, Mansoura University, Mansoura, Egypt
| | - Mohsen M Mostafa
- Chemistry Department, Faculty of Science, Mansoura University, Mansoura, Egypt.
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8
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Cheng F, He C, Ren M, Wang F, Yang Y. Two dinuclear Ru(II) polypyridyl complexes with different photophysical and cation recognition properties. Spectrochim Acta A Mol Biomol Spectrosc 2015; 136 Pt B:845-851. [PMID: 25459607 DOI: 10.1016/j.saa.2014.09.103] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2014] [Revised: 08/21/2014] [Accepted: 09/11/2014] [Indexed: 06/04/2023]
Abstract
Two dinuclear Ru(II) polypyridyl complexes functionalized with vacant coordination sites have been designed and synthesized. Their photophysical properties and interactions with various metal ions have been investigated at room temperature. The two complexes exhibit different UV/Vis absorption and emission intensities. When titrated with various metal ions, complex [{Ru(bpy)2}2(μ2-L(1))](4+) exhibits a notable fluorescence quenching in the presence of Cu(2+) in H2O-CH3CN media (1:1, v/v); its analogous complex [{Ru(bpy)2}2(μ2-L(2))](4+) exhibits no cation selectivity, the fluorescence intensity of complex [{Ru(bpy)2}2(μ2-L(2))](4+) has been enhanced by several transition metal ions due to prevention of the photo-induced electron transfer process. The fluorescence titration spectra and Benesi-Hildebrand expression reveal the formation of a 1:1 bonding mode between [{Ru(bpy)2}2(μ2-L(1))](4+) and Cu(2+) ion with the association constant of 5.50×10(4) M(-1).
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Affiliation(s)
- Feixiang Cheng
- College of Chemistry and Chemical Engineering, Qujing Normal University, Qujing 655011, PR China.
| | - Chixian He
- College of Chemistry and Chemical Engineering, Qujing Normal University, Qujing 655011, PR China
| | - Mingli Ren
- College of Chemistry and Chemical Engineering, Qujing Normal University, Qujing 655011, PR China
| | - Fan Wang
- College of Chemistry and Chemical Engineering, Qujing Normal University, Qujing 655011, PR China
| | - Yuting Yang
- College of Chemistry and Chemical Engineering, Qujing Normal University, Qujing 655011, PR China
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9
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Onwudiwe DC, Strydom CA. The bipyridine adducts of N-phenyldithiocarbamato complexes of Zn(II) and Cd(II); synthesis, spectral, thermal decomposition studies and use as precursors for ZnS and CdS nanoparticles. Spectrochim Acta A Mol Biomol Spectrosc 2015; 135:1080-9. [PMID: 25173525 DOI: 10.1016/j.saa.2014.08.004] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2014] [Revised: 06/19/2014] [Accepted: 08/04/2014] [Indexed: 05/28/2023]
Abstract
Bipyridine adducts of N-phenyldithiocarbamato complexes, [ML(1)2L(2)] (M=Cd(II), Zn(II); L(1)=N-phenyldithiocarbamate, L(2)=2,2' bipyridine), have been synthesized and characterised. The decomposition of these complexes to metal sulphides has been investigated by thermogravimetric analysis (TGA). The complexes were used as single-source precursors to synthesize MS (M=Zn, Cd) nanoparticles (NPs) passivated by hexadecyl amine (HDA). The growth of the nanoparticles was carried out at two different temperatures: 180 and 220 °C, and the optical and structural properties of the nanoparticles were studied using UV-Vis spectroscopy, photoluminescence spectroscopy (PL), transmission emission microscopy (TEM) and powdered X-ray diffraction (p-XRD). Nanoparticles, whose average diameters are 2.90 and 3.54 nm for ZnS, and 8.96 and 9.76 nm for CdS grown at 180 and 220 °C respectively, were obtained.
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Affiliation(s)
- Damian C Onwudiwe
- Chemical Resource Beneficiation (CRB) Research Focus Area, North-West University, Private Bag X6001, Potchefstroom 2520, South Africa.
| | - Christien A Strydom
- Chemical Resource Beneficiation (CRB) Research Focus Area, North-West University, Private Bag X6001, Potchefstroom 2520, South Africa
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10
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Fayed AM, Elsayed SA, El-Hendawy AM, Mostafa MR. Complexes of cis-dioxomolybdenum(VI) and oxovanadium(IV) with a tridentate ONS donor ligand: synthesis, spectroscopic properties, X-ray crystal structure and catalytic activity. Spectrochim Acta A Mol Biomol Spectrosc 2014; 129:293-302. [PMID: 24747851 DOI: 10.1016/j.saa.2014.03.064] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/13/2014] [Revised: 03/13/2014] [Accepted: 03/21/2014] [Indexed: 06/03/2023]
Abstract
New cis-dioxomolybdenum(VI) and oxovanadium(IV) complexes of the Schiff base, derived from S-methyl dithiocarbazate and 2,3-dihydroxybenzaldehyde (H2dhsm), have been synthesized. The complexes of the type cis-[MoO2(dhsm)] (1a), cis-[MoO2(dhsm)(D)] (1b-1d) [D=neutral monodentate ligand; EtOH, pyridine (py) or imidazole (imz)], [VO(dhsm)(NN)] (2a, 2b) [NN=2,2'-bipyridine (bipy) or 1,10-phenanthroline (phen)] and [VO(dhsm)] (2c) have been isolated, characterized by (1)H NMR, IR, UV-Vis and EPR spectral studies and investigated by cyclic voltammetry. The X-ray crystal structure of cis-[MoO2(dhsm)(EtOH)] (1b) has been determined and shows that the complex has a distorted octahedral geometry in which the H2dhsm behaves as a dianionic ONS tridentate ligand coordinating via phenoxide oxygen, hydrazinic nitrogen and thiolate sulfur. The oxomolybdenum(IV) complex [MoO(dhsm)] (1e) has obtained from dioxomolybdenum(VI) complex (1b) by oxo abstraction with PPh3. The reactivity of the complexes toward catalytic oxidation of alcohols in the presence of H2O2 and t-BuOOH as co-oxidants under solvent free conditions is reported.
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Affiliation(s)
- Ahmed M Fayed
- Department of Chemistry, Faculty of Science, Damietta University, Damietta, Egypt
| | - Shadia A Elsayed
- Department of Chemistry, Faculty of Science, Damietta University, Damietta, Egypt
| | - Ahmed M El-Hendawy
- Department of Chemistry, Faculty of Science, Damietta University, Damietta, Egypt.
| | - Mohamed R Mostafa
- Department of Chemistry, Faculty of Science, Damietta University, Damietta, Egypt
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11
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Al-Noaimi M, Abdel-Rahman OS, Fasfous II, El-khateeb M, Awwadi FF, Warad I. Ruthenium(II) bipyridine complexes bearing quinoline-azoimine (NN'N″) tridentate ligands: synthesis, spectral characterization, electrochemical properties and single-crystal X-ray structure analysis. Spectrochim Acta A Mol Biomol Spectrosc 2014; 125:375-383. [PMID: 24566116 DOI: 10.1016/j.saa.2014.01.075] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/2013] [Revised: 01/08/2014] [Accepted: 01/14/2014] [Indexed: 06/03/2023]
Abstract
Four octahedral ruthenium(II) azoimine-quinoline complexes having the general molecular formula [Ru(II)(L-Y)(bpy)Cl](PF6) {L-Y=YC6H4N=NC(COCH3)=NC9H6N, Y=H (1), CH3 (2), Br (3), NO2 (4) and bpy=2,2'-bipyrdine} were synthesized. The azoimine-quinoline based ligands behave as NN'N″ tridentate donors and coordinated to ruthenium via azo-N', imine-N' and quinolone-N″ nitrogen atoms. The composition of the complexes has been established by elemental analysis, spectral methods (FT-IR, electronic, (1)H NMR, UV/Vis and electrochemical (cyclic voltammetry) techniques. The crystal structure of complex 1 is reported. The Ru(II) oxidation state is greatly stabilized by the novel tridentate ligands, showing Ru(III/II) couples ranging from 0.93-1.27 V vs. Cp2Fe/Cp2Fe(+). The absorption spectrum of 1 in dichloromethane was modeled by time-dependent density functional theory (TD-DFT).
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Affiliation(s)
- Mousa Al-Noaimi
- Department of Chemistry, Hashemite University, P.O. Box 150459, Zarqa 13115, Jordan.
| | - Obadah S Abdel-Rahman
- Fachbereich Chemie der Universität Konstanz, Universitätstraße 10, D-78457 Konstanz, Germany
| | - Ismail I Fasfous
- Department of Chemistry, Hashemite University, P.O. Box 150459, Zarqa 13115, Jordan
| | - Mohammad El-khateeb
- Chemistry Department, Faculty of Science and Arts, Jordan University of Science and Technology, Irbid 22110, Jordan
| | - Firas F Awwadi
- Department of Chemistry, The University of Jordan, Amman 11942, Jordan
| | - Ismail Warad
- Department of Chemistry, AN-Najah National University, Nablus, Occupied Palestinian Territory
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12
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Zhao J, Cheng Y, Shang S, Zhang F, Chen L, Chen L. Syntheses, structures and properties of three new two-dimensional Cu(I)-Ln(III) heterometallic coordination polymers based on 2,2'-dipyridyl-5,5'-dicarboxylate ligands. Spectrochim Acta A Mol Biomol Spectrosc 2013; 116:348-354. [PMID: 23973577 DOI: 10.1016/j.saa.2013.07.079] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/12/2013] [Revised: 07/04/2013] [Accepted: 07/25/2013] [Indexed: 06/02/2023]
Abstract
Three new two-dimensional Cu(I)-Ln(III) heterometallic coordination polymers [Ln(III)Cu2(I)(Hbpdc)4] · Cl · xH2O [Ln(III) = La(III), x = 8 (1); Ln(III) = Pr(III), x=9 (2); Ln(III) = Eu(III), x = 8 (3)] (H2bpdc = 2,2'-bipyridyl-5,5'-dicarboxylic acid) have been prepared under hydrothermal conditions and structurally characterized by elemental analyses, inductively coupled plasma atomic emission spectrometry (ICP-AES) analyses, IR spectra, X-ray photoelectron spectroscopy (XPS) and single-crystal X-ray diffraction. X-ray diffraction indicates that the isomorphic 1-3 display the two-dimensional sheet structure constructed from [Cu(I)(Hbpdc)2](-) fragments through Ln(3+) connectors. Moreover, the solid-state photoluminescence measurements of 3 indicate that the Eu(III) ions, Hbpdc(-) ligands and Cu(I) cations make contributions to its luminescent properties simultaneously.
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Affiliation(s)
- Junwei Zhao
- Henan Key Laboratory of Polyoxometalate Chemistry, College of Chemistry and Chemical Engineering, Henan University, Kaifeng, Henan 475004, PR China; State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian 350002, PR China.
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13
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Veikko U, Zhang X, Peng T, Cai P, Cheng G. The synthesis and characterization of dinuclear ruthenium sensitizers and their applications in photocatalytic hydrogen production. Spectrochim Acta A Mol Biomol Spectrosc 2013; 105:539-44. [PMID: 23353692 DOI: 10.1016/j.saa.2012.12.061] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2012] [Revised: 12/11/2012] [Accepted: 12/13/2012] [Indexed: 05/24/2023]
Abstract
A dinuclear ruthenium(II) dye sensitizer, ([Ru(2)(bpy)(4)BL](ClO(4))(2)) referred as Compound 1, where bpy=2,2'-bipyridine, BL=2,2'-((1E,1'E)-(((E)-diazene-1,2-diyl-bis(2,1-phenylene))-bis(azanylylidene))-bis (methanylylidene)) diphenol (a bidentate bridging ligand), was designed, synthesized and characterized. The dye sensitizer was used on the photocatalytic water splitting for hydrogen (H(2)) production over TiO(2) (P25) under visible light (λ≥400 nm) irradiation using triethanolamine (TEOA) as a sacrificial electron donor. The dye sensitized-TiO(2) demonstrated a good stability and sufficient reproducibility for over 6 h. The photosensitization ability of the sensitizer was due to its conjugation system, large molecular area, TiO(2) linkage mode and the antenna effect.
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Affiliation(s)
- Uahengo Veikko
- College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, China
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14
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Patel MN, Parmar PA, Gandhi DS, Patidar AP. DNA interactions and cytotoxic studies of cis-platin analogues of substituted 2,2'-bipyridines. Spectrochim Acta A Mol Biomol Spectrosc 2012; 97:54-59. [PMID: 22750337 DOI: 10.1016/j.saa.2012.05.043] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/10/2012] [Revised: 04/28/2012] [Accepted: 05/17/2012] [Indexed: 06/01/2023]
Abstract
Platinum(II) complexes [Pt(4″-fpbpy)Cl(2)] (1), [Pt(4″-mepbpy)Cl(2)] (2), [Pt(4″-mpbpy)Cl(2)] (3) and [Pt(4″-bopbpy)Cl(2)] (4) {where 4″-fpbpy=4-(4″-fluorophenyl)-6-phenyl-2,2'-bipyridine, 4″-mepbpy=4-(4″-methylphenyl)-6-phenyl-2,2'-bipyridine, 4″-mpbpy=4-(4″-methoxyphenyl)-6-phenyl-2,2'-bipyridine, 4″-bopbpy=4-(4″-benzyloxyphenyl)-6-phenyl-2,2'-bipyridine} have been synthesized and characterized. The binding strength and binding mode of the complexes with HS DNA (Herring Sperm) have been investigated by absorption titration and viscosity measurement studies. The results have been revealed that the complexes bind to DNA by covalent mode with intrinsic binding constant K(b) ranging from 6.05×10(4)M(-1) to 3.48×10(5)M(-1). The unwinding angle of pUC19 DNA has been evaluated by gel electrophoresis assay. The brine shrimp bioassay has been performed to study the in vitro cytotoxic properties of the synthesized metal complexes.
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Affiliation(s)
- Mohan N Patel
- Department of Chemistry, Sardar Patel University, Vallabh Vidyanagar 388 120, Gujarat, India.
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15
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Mohamed MS, Shoukry AA, Ali AG. Synthesis and structural characterization of ternary Cu (II) complexes of glycine with 2,2'-bipyridine and 2,2'-dipyridylamine. The DNA-binding studies and biological activity. Spectrochim Acta A Mol Biomol Spectrosc 2012; 86:562-570. [PMID: 22153742 DOI: 10.1016/j.saa.2011.11.015] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/12/2011] [Revised: 11/06/2011] [Accepted: 11/09/2011] [Indexed: 05/31/2023]
Abstract
In this study two new complexes [Cu(bpy)(Gly)Cl]·2H(2)O (1) and [Cu(dpa)(Gly)Cl]·2H(2)O (2) (bpy=2,2'-bipyridine; dpa=2,2'-dipyridylamine, Gly=glycine) have been synthesized and characterized by elemental analysis, IR, TGA, UV-vis and magnetic susceptibility measurements. The binding properties of the complexes with CT-DNA were investigated by electronic absorption spectra. The intrinsic binding constants (K(b)) calculated from UV-vis absorption studies were 1.84 × 10(3) M(-1) and 3.1 × 10(3) M(-1) for complexes 1 and 2 respectively. Thermal denaturation has been systematically studied by spectrophotometric method and the calculated ΔT(m) was nearly 5 °C for each complex. All the results suggest that the interaction modes between the complexes and CT-DNA were electrostatic and/or groove binding. The redox behavior of the two complexes was investigated by cyclic voltammetry. Both complexes, in presence and absence of CT-DNA show a quasi-reversible wave corresponding to Cu(II)/Cu(I) redox couple. The change in E(1/2), ΔE and I(pc)/I(pa) ascertain the interaction of complexes 1 and 2 with CT-DNA. Further insight into the binding of complexes with CT-DNA has been made by gel electrophoresis, where the binding of complexes is confirmed through decreasing the mobility and intensity of DNA bands. In addition, the antitumor activity of the complexes was tested on two cancer cell lines; the breast cancer (MCF7) and the human hepatocellular carcinoma (HEPG2), as well as one normal cell line; the human normal melanocytes (HFB4). The results showed that complex 1 was more potent antitumor agent than complex 2. The in-vitro antimicrobial activity of the two complexes was carried out using the disc diffusion method against different species of pathogenic bacteria and fungi. The activity data showed that complex 2 was more active in inhibiting the growth of the tested organisms.
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Affiliation(s)
- Mervat S Mohamed
- Department of Chemistry, Biochemistry Speciality, Faculty of Science, Cairo University, Egypt
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16
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Turrell SJ, Filby MH, Whitehouse A, Wilson AJ. Cellular uptake of highly-functionalized ruthenium(II) tris-bipyridine protein-surface mimetics. Bioorg Med Chem Lett 2011; 22:985-8. [PMID: 22204913 DOI: 10.1016/j.bmcl.2011.12.007] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2011] [Revised: 11/30/2011] [Accepted: 12/01/2011] [Indexed: 11/18/2022]
Abstract
This manuscript describes cell-uptake studies with HEK 293T cells on a series of ruthenium complexes shown previously to act as receptors for protein surface recognition and was motivated by a desire to establish if these receptors represent suitable templates for further elaboration as inhibitors of protein-protein interactions. The results illustrate that large (>3000Da) highly functionalized anionic ruthenium complexes are efficiently transfected via endocytosis to lysosomes with negligible toxicity.
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Affiliation(s)
- Susan J Turrell
- Astbury Centre for Structural Molecular Biology, University of Leeds, Woodhouse Lane, Leeds LS2 9JT, United Kingdom; Institute of Molecular and Cellular Biology, University of Leeds, Woodhouse Lane, Leeds LS2 9JT, United Kingdom
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17
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Dixit N, Mishra L, Mustafi SM, Chary KVR, Houjou H. Synthesis of a ruthenium(II) bipyridyl complex coordinated by a functionalized Schiff base ligand: characterization, spectroscopic and isothermal titration calorimetry measurements of M2+ binding and sensing (M2+=Ca2+, Mg2+). Spectrochim Acta A Mol Biomol Spectrosc 2009; 73:29-34. [PMID: 19230747 DOI: 10.1016/j.saa.2009.01.015] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/01/2008] [Revised: 12/17/2008] [Accepted: 01/14/2009] [Indexed: 05/27/2023]
Abstract
Bis-[methylsalicylidine-4'benzoic acid]-ethylene (LH2) complexed with cis-Ru(bpy)2Cl(2).2H2O provides a complex of composition [Ru(bpy)2L].2NH4PF6 (1), which has been characterized spectroscopically. Its binding behaviour towards Mg2+ and Ca2+ ions is monitored using 1H NMR titration, isothermal titration calorimetry (ITC) and luminescence microscopy. The luminescent ruthenium complex binds Ca2+ in a more selective manner as compared to Mg2+.
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Affiliation(s)
- Namrata Dixit
- Department of Chemistry, Faculty of Science, Banaras Hindu University, Varanasi- 221 005, India
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18
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Abstract
Studies of metabolic enzyme inhibition are necessary in drug development and toxicity investigations as potential tools to limit or prevent appearance of deleterious metabolites formed, for example, by cytochrome (cyt) P450 enzymes. In this paper, we evaluate the use of enzyme/DNA toxicity biosensors as tools to investigate enzyme inhibition. We have examined DNA damage due to cyt P450cam metabolism of styrene using DNA/enzyme films on pyrolytic graphite (PG) electrodes monitored via Ru(bpy)(3)(2+)-mediated DNA oxidation. Styrene metabolism initiated by hydrogen peroxide was evaluated with and without the inhibitors, imidazole, imidazole-4-acetic acid, and sulconazole (in micromolar range) to monitor DNA damage inhibition. The initial rates of DNA damage decreased with increased inhibitor concentrations. Linear and nonlinear fits of Michaelis-Menten inhibition models were used to determine apparent inhibition constants (K(I)*) for the inhibitors. Elucidation of the best fitting inhibition model was achieved by comparing correlation coefficients and the sum of the square of the errors (SSE) from each inhibition model. Results confirmed the utility of the enzyme/DNA biosensor for metabolic inhibition studies. A simple competitive inhibition model best approximated the data for imidazole, imidazole-4-acetic acid and sulconazole with K(I)* of 268.2, 142.3, and 204.2 microM, respectively.
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Affiliation(s)
- Dominic O. Hull
- Department of Chemistry and Institute of Materials Science, 55 N. Eagleville Road, University of Connecticut, Storrs, Connecticut 06269
| | - Besnik Bajrami
- Department of Chemistry and Institute of Materials Science, 55 N. Eagleville Road, University of Connecticut, Storrs, Connecticut 06269
| | - Ingela Jansson
- Department of Cell Biology, University of Connecticut Health Center, Farmington, Connecticut 06032
| | - John B. Schenkman
- Department of Cell Biology, University of Connecticut Health Center, Farmington, Connecticut 06032
| | - James F. Rusling
- Department of Chemistry and Institute of Materials Science, 55 N. Eagleville Road, University of Connecticut, Storrs, Connecticut 06269
- Department of Cell Biology, University of Connecticut Health Center, Farmington, Connecticut 06032
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19
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Mishra L, Prajapati R, Pandey KK. Mixed-ligand Ru(II) complexes with 2,2'-bipyridine and tetradentate Schiff bases auxiliary ligands: Synthesis, physico-chemical study, DFT analysis, electrochemical and Na+ binding properties. Spectrochim Acta A Mol Biomol Spectrosc 2008; 70:79-85. [PMID: 17719837 DOI: 10.1016/j.saa.2007.07.017] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/02/2007] [Revised: 06/28/2007] [Accepted: 07/12/2007] [Indexed: 05/16/2023]
Abstract
cis-Bis(2,2'-bipyridyl)dichlororuthenium(II)dihydrate complexed with Schiff bases salen (L1H2) and salophen (L2H2) provides complexes of compositions [Ru(L1)(bpy)2] 1 and [Ru(L2)(bpy)2] 2, respectively with cavity. The structure of these complexes characterized by spectroscopic studies were supported by their optimized geometries based on DFT calculations. Complexes 1 and 2 were then allowed to interact with methanolic solution of sodium perchlorate separately providing corresponding complexes 3 and 4 with the compositions 1.NaClO4 and 2.NaClO4, respectively. The formation constants were then evaluated by monitoring the changes in their UV-visible spectral features upon addition of different amount of sodium salts in the presence of a fixed concentration of the ruthenium complexes at a wavelength 294 nm. Emission (solution), luminescence microscopic and cyclic voltammetric studies of these complexes have also been made.
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Affiliation(s)
- Lallan Mishra
- Department of Chemistry, Faculty of Science, Banaras Hindu University, Varanasi 221005, India.
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20
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Brazier JA, Onishi I, Sasaki S. Binding of two bis-bipyridine minor groove binders to a DNA template in the presence of Cu2+ ions. Nucleic Acids Symp Ser (Oxf) 2008; 52:107-108. [PMID: 18776276 DOI: 10.1093/nass/nrn055] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Some diseases are associated with abnormally extended regions of triplet repeats. These repeating regions are an attractive target for both diagnostic and therapeutic goals. In an attempt to approach to this goal, we have focused on establishment of an allosteric binding mechanism, in which the binding of the ligand promotes the next ligand binding. In the previous study, we already reported that the ligand having the bipyridine unit for binding with Cu(2+) and the Hoechst33258 for binding to A(3)T(3) site displayed Cu(2+)- mediated assembly on the DNA with two A(3)T(3) sites. In this study, we synthesized the new ligands containing two bipyridine units attached to Hoechst33258 by different length linkers. It was expected that the bipyridine-Cu(2+) complexation would enhance assembly of a number of the ligand on the DNA sequence with repeating regions. UV spectroscopy has been used to demonstrate the binding of these ligands to a DNA template mediated by the complexation of Cu(2+) ions.
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Affiliation(s)
- John A Brazier
- Graduate School of Pharmaceutical Sciences, Kyushu University, Higashi-ku, Fukuoka 812-8582, Japan
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21
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Song XQ, Zheng JR, Liu WS, Ju ZH. Synthesis, structure and spectroscopic properties of rare earth complexes with a new aryl amide 2,2'-bipyridine derivative. Spectrochim Acta A Mol Biomol Spectrosc 2008; 69:49-55. [PMID: 17482511 DOI: 10.1016/j.saa.2007.03.007] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/04/2007] [Revised: 02/14/2007] [Accepted: 03/09/2007] [Indexed: 05/15/2023]
Abstract
Solid complexes of rare earth nitrates and picrates with a new aryl amide ligand 3.3'-bis(benzylamido)-2,2'-bipyridine (L) were synthesized and characterized by elemental analysis, IR and molar conductivity measurements. The molecular structures of the complex [TbL(2)(NO(3))(3)H(2)O].2H(2)O have been determined by single-crystal X-ray diffraction. The fluorescent properties of the Eu(III) and Tb(III) nitrates and picrates complexes in solid state were also investigated in detail. Under the excitation, these complexes exhibited characteristic emissions of europium and terbium ions. It is worth noting that the nature of the anion has a great effect upon the composition of the complexes as well as emission properties of them.
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Affiliation(s)
- Xue-Qin Song
- State Key Laboratory of Applied Organic Chemistry, Lanzhou university, Lanzhou 730000, China
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22
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Lo KKW, Zhang KY, Chung CK, Kwok KY. Synthesis, photophysical and electrochemical properties, and protein-binding studies of luminescent cyclometalated iridium(III) bipyridine estradiol conjugates. Chemistry 2007; 13:7110-20. [PMID: 17566135 DOI: 10.1002/chem.200700530] [Citation(s) in RCA: 100] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
A new series of luminescent cyclometalated iridium(III) bipyridine estradiol conjugates [Ir(N-C)2(N-N)](PF6) (N-N = 5-(4-(17alpha-ethynylestradiolyl)phenyl)-2,2'-bipyridine, bpy-est, HN-C = 2-phenylpyridine, Hppy (1 a), 1-phenylpyrazole, Hppz (2 a), 7,8-benzoquinoline, Hbzq (3 a), 2-phenylquinoline, Hpq (4 a), 2-((1,1'-biphenyl)-4-yl)benzothiazole, Hbsb (5 a); N-N = 4-(N-(6-(4-(17alpha-ethynylestradiolyl)benzoylamino)hexyl)aminocarbonyl)-4'-methyl-2,2'-bipyridine, bpy-C6-est, HN-C = Hppy (1 b), Hppz (2 b), Hbzq (3 b), Hpq (4 b), Hbsb (5 b)) was synthesized, characterized, and their photophysical and electrochemical properties studied. Upon photoexcitation, all the complexes displayed intense and long-lived emission in fluid solutions at 298 K and in low-temperature glass. The emission of complexes 1 a-3 a and 1 b-3 b was assigned to a triplet metal-to-ligand charge-transfer ((3)MLCT) (dpi(Ir)-->pi*(bpy-est and N-C-)) state mixed with some triplet intraligand ((3)IL) (pi-->pi*) (N-C- and N-N) character. However, the emissive states of the pq- and bsb- complexes 4 a, 4 b, 5 a, and 5 b showed substantial (3)IL (pi-->pi*) (pq-/bsb-) character. The lipophilicity of all the complexes was determined by reversed-phase HPLC. Upon binding to estrogen receptor alpha, all of these iridium(III) estradiol conjugates exhibited emission enhancement and lifetime extension, rendering them a novel series of luminescent probes for this receptor.
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Affiliation(s)
- Kenneth Kam-Wing Lo
- Department of Biology and Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, People's Republic of China.
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Tanaka K, Tainaka K, Kamei T, Okamoto A. Development of fluorescence-labeling method for methylcytosine with metal complexation. ACTA ACUST UNITED AC 2007:135-6. [PMID: 17150854 DOI: 10.1093/nass/nrl067] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
We report a methylcytosine-selective fluorescence labeling. An amino-modified bipyridine was prepared and used as an osmium ligand for methylcytosine-selective oxidation. Different fluorophores were easily incorporated to the modified methylcytosine site through an amide formation of the ligand amino group after osmium complexation.
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Affiliation(s)
- Kazuo Tanaka
- Frontier Research System, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
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24
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Chaka G, Sonnenberg JL, Schlegel HB, Heeg MJ, Jaeger G, Nelson TJ, Ochrymowycz LA, Rorabacher DB. A definitive example of a geometric "entatic state" effect: electron-transfer kinetics for a copper(II/I) complex involving A quinquedentate macrocyclic trithiaether-bipyridine ligand. J Am Chem Soc 2007; 129:5217-27. [PMID: 17391036 DOI: 10.1021/ja068960u] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The quinquedentate macrocyclic ligand cyclo-6,6'-[1,9-(2,5,8-trithianonane)]-2,2'-bipyridine ([15]aneS3bpy = L), containing two pyridyl nitrogens and three thiaether sulfurs as donor atoms, has been synthesized and complexed with copper. The CuII/IL redox potential, the stabilities of the oxidized and reduced complex, and the oxidation and reduction electron-transfer kinetics of the complex reacting with a series of six counter reagents have been studied in acetonitrile at 25 degrees C, mu = 0.10 M (NaClO4). The Marcus cross relationship has been applied to the rate constants obtained for the reactions with each of the six counter reagents to permit the evaluation of the electron self-exchange rate constant, k11. The latter value has also been determined independently from NMR line-broadening experiments. The cumulative data are consistent with a value of k11 = 1 x 10(5) M(-1) s(-1), ranking this among the fastest-reacting CuII/I systems, on a par with the blue copper proteins known as cupredoxins. The resolved crystal structures show that the geometry of the CuIIL and CuIL complexes are nearly identical, both exhibiting a five-coordinate square pyramidal geometry with the central sulfur donor atom occupying the apical site. The most notable geometric difference is a puckering of an ethylene bridge between two sulfur donor atoms in the CuIL complex. Theoretical calculations suggest that the reorganizational energy is relatively small, with the transition-state geometry more closely approximating the geometry of the CuIIL ground state. The combination of a nearly constant geometry and a large self-exchange rate constant implies that this CuII/I redox system represents a true geometric "entatic state."
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Affiliation(s)
- Gezahegn Chaka
- Department of Chemistry, Wayne State University, Detroit, Michigan 48202, USA
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25
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Abstract
Two highly charged cationic copper(II) complexes have been synthesized and characterized structurally and spectroscopically: [Cu(L1)2(Br)](ClO4)5 (1) and [Cu(L2)2(Br)](ClO4)5 (2) (L1= 5,5'-di(1-(triethylammonio)methyl)-2,2'-dipyridyl cation and L2= 5,5'-di(1-(tributylammonio)methyl)-2,2'-dipyridyl cation bidentate ligands). X-Ray structures show that Cu(II) ions in both complexes have a trigonal-bipyramidal CuN4Br-configuration. Two nitrogen atoms of the electropositive pendants and coordinated bromine atom basically array in a straight line. Their close distances of N[dot dot dot]Br atoms are 5.772 and 5.594 A, respectively, which is comparable to that of adjacent phosphodiesters in B-form DNA (ca. 6 A). In the absence of reducing agent, supercoiled plasmid DNA cleavage by the complexes has been performed and their hydrolytic mechanisms have been investigated. The pseudo-Michaelis-Menten kinetic parameters (kcat), 4.15 h(-1) for 1, 0.43 h(-1) for 2 and 0.61 h(-1) for [Cu(bipy)(NO3)2], were obtained. This result indicates that 1 exhibits markedly higher nuclease activity than its corresponding analogues. The high ability of DNA cleavage for 1 is attributed to the effective cooperation of the metal moiety and two positive pendants since the array of linear tri-binding sites matches with one of three phosphodiester backbones of nucleic acid.
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Affiliation(s)
- Yan An
- School of Chemistry and Chemical Engineering, Sun Yat-Sen University, Guangzhou, 510275, China.
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26
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Tanaka K, Tainaka K, Kamei T, Okamoto A. Development of electrochemical detection for methylcytosine and its application. Nucleic Acids Symp Ser (Oxf) 2006:141-2. [PMID: 17150857 DOI: 10.1093/nass/nrl070] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
We report electrochemical detection of methylcytosine. We developed a bipyridine ligand possessing an amino linker. This ligand was used for methylcytosine-selective osmium oxidation and subsequent redox labeling. The DNA labeled methylcytosine selectively with anthraquinone showed the current signal through hybridization with a DNA probe fixed on a gold surface.
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Affiliation(s)
- Kazuo Tanaka
- Frontier Research System, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
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27
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Branowska D. Synthesis of unsymmetrical annulated 2,2'-bipyridine analogues with attached cycloalkene and piperidine rings via sequential Diels-Alder Reaction of 5,5'-bi-1,2,4-triazines. Molecules 2005; 10:265-73. [PMID: 18007295 PMCID: PMC6147554 DOI: 10.3390/10010265] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2004] [Accepted: 09/22/2004] [Indexed: 11/24/2022] Open
Abstract
Synthesis of bisfunctionalized unsymmetrical 2,2’-bipyridines 8 or their sulfonyl derivatives 12a,b are described. They were prepared via the Diels-Alder reaction of 1‑methyl-4-pyrrolidin-1-yl-1,2,3,6-tetrahydropyridine (6) with 3,3’-bis(methyl-sulfanyl)-5,5’-bi-1,2,4-triazine (1). The reaction leads to the single cycloaddition product 7 which undergoes Diels-Alder reaction with cyclic enamines 2a,b to give unsymmetrical 2,2’-bipyridine derivatives 8, consisting of the two different heterocyclic units: cycloalkeno[c]pyridine and 2,6-naphthyridine.
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Affiliation(s)
- D Branowska
- Institute of Chemistry, University of Podlasie, PL-08-110 Siedlce, Poland.
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28
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Abstract
We have investigated light-triggered or catalytically activated precipitation agents and have proposed the name "precipiton" for such molecules or molecular fragments. A phase separation is induced when the precipiton isomerizes to a low-solubility form. In this paper we describe the first intramolecularly activated precipitons. The isomerization process is induced by intramolecular triplet energy transfer from a covalently attached metal complex. As expected, intramolecular sensitization leads to a more rapid isomerization than can be achieved by intermolecular sensitization at accessible concentrations. Two isomeric bichromophoric precipiton species, each containing [Ru(bpy)(3)](2+) and 1,2-bis(biphenyl)ethene units covalently linked together by an ether tether, have been synthesized and characterized, and their photochemical properties have been investigated. The rates of photoisomerization of these complexes, [((Z)-1,2-bis(biphenyl)ethene-bpy)Ru(bpy)(2)](PF(6))(2) (2Z) and [((E)-1,2-bis(biphenyl)ethene-bpy)Ru(bpy)(2)](PF(6))(2) (2E), were compared to those of their untethered analogues, (Z)-1,2-bis(biphenyl)ethene-OTBS (1Z) and (E)-1,2-bis(biphenyl)ethene-OTBS (1E), where ruthenium sensitization occurred through an intermolecular pathway. Upon irradiation with visible light (lambda > or = 400 nm) in degassed solution, 2Z/E and 1Z/E obeyed reversible first-order rate kinetics. The intramolecularly sensitized precipiton 2Z isomerized 250 times faster (k(2Z-->2E) = 1.0 x 10(-3) s(-1) with a 51% neutral density filter) than the intermolecular case 1Z (k(1Z-->1E) = 0.80 x 10(-5) s(-1)). For 1E and 2E, the isomerization rates were k(1E-->1Z) = 11.0 x 10(-5) s(-1) and k(2E-->2Z) = 1.6 x 10(-3) s(-1), respectively. The average Z/E mole ratio at the photostationary state was 62/38 for 2Z/E and 93/7 for 1Z/E. The impetus for this study was our desire to evaluate the possibility of using metal-binding precipitons that would precipitate only upon metal-to-precipiton binding and would be inert to visible light in the absence of metals.
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Affiliation(s)
- Mark R Ams
- Department of Chemistry and The Combinatorial Chemistry Center, University of Pittsburgh, Pittsburgh, PA 15260, USA
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Xu Y, Eilers G, Borgström M, Pan J, Abrahamsson M, Magnuson A, Lomoth R, Bergquist J, Polívka T, Sun L, Sundström V, Styring S, Hammarström L, Akermark B. Synthesis and Characterization of Dinuclear Ruthenium Complexes Covalently Linked to RuII Tris-bipyridine: An Approach to Mimics of the Donor Side of Photosystem II. Chemistry 2005; 11:7305-14. [PMID: 16163754 DOI: 10.1002/chem.200500592] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
To mimic the electron-donor side of photosystem II (PSII), three trinuclear ruthenium complexes (2, 2a, 2b) were synthesized. In these complexes, a mixed-valent dinuclear Ru2(II,III) moiety with one phenoxy and two acetato bridges is covalently linked to a Ru(II) tris-bipyridine photosensitizer. The properties and photoinduced electron/energy transfer of these complexes were studied. The results show that the Ru2(II,III) moieties in the complexes readily undergo reversible one-electron reduction and one-electron oxidation to give the Ru2(II,III) and Ru2(III,III) states, respectively. This could allow for photooxidation of the sensitizer part with an external acceptor and subsequent electron transfer from the dinuclear ruthenium moiety to regenerate the sensitizer. However, all trinuclear ruthenium complexes have a very short excited-state lifetime, in the range of a few nanoseconds to less than 100 ps. Studies by femtosecond time-resolved techniques suggest that a mixture of intramolecular energy and electron transfer between the dinuclear ruthenium moiety and the excited [Ru(bpy)3]2+ photosensitizer is responsible for the short lifetimes. This problem is overcome by anchoring the complexes with ester- or carboxyl-substituted bipyridine ligands (2a, 2b) to nanocrystalline TiO2, and the desired electron transfer from the excited state of the [Ru(bpy)3]2+ moiety to the conduction band of TiO2 followed by intramolecular electron transfer from the dinuclear Ru2(II,III) moiety to photogenerated Ru(III) was observed. The resulting long-lived Ru2(III,III) state decays on the millisecond timescale.
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Affiliation(s)
- Yunhua Xu
- Department of Organic Chemistry, Arrhenius Laboratories, Stockholm University, 106 91 Stockholm, Sweden
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Lainé PP, Ciofini I, Ochsenbein P, Amouyal E, Adamo C, Bedioui F. Photoinduced Processes within Compact Dyads Based on Triphenylpyridinium-Functionalized Bipyridyl Complexes of Ruthenium(II). Chemistry 2005; 11:3711-27. [PMID: 15822134 DOI: 10.1002/chem.200401150] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
As an alternative to conventional charge-separation functional molecular models based on long-range ET within redox cascades, a "compact approach" has been examined. To this end, spacer elements usually inserted between main redox-active units within polyad systems have been removed, allowing extended rigidity but at the expense of enhanced intercomponent electronic communication. The molecular assemblies investigated here are of the P-(theta (1))-A type, where the theta (1) twist angle is related to the degree of conjugation between the photosensitizer (P, of {Ru(bpy)(3)}(2+) type) and the electron-acceptor (A). 4-N- and 4-N-,4'-N-(2,4,6-triphenylpyridinio)-2,2'-bipyridine ligands (A(1)-bpy and A(2)-bpy, respectively) have been synthesized to give complexes with Ru(II), 1-bpy and 2-bpy, respectively. Combined solid-state analysis (X-ray crystallography), solution studies ((1)H NMR, cyclic voltammetry) and computational structural optimization allowed verifying that theta (1) angle approaches 90 degrees within 1-bpy and 2-bpy in solution. Also, anticipated existence of strong intercomponent electronic coupling has been confirmed by investigating electronic absorption properties and electrochemical behavior of the compounds. The capability of 1-bpy and 2-bpy to undergo PET process was evaluated by carrying out their photophysical study (steady state emission and time-resolved spectroscopy at both 293 and 77 K). The conformational dependence of photoinduced processes within P-(theta (1))-A systems has been established by comparing the photophysical properties of 1-bpy (and 2-bpy) with those of an affiliated species reported in the literature, 1-phen. A complementary theoretical analysis (DFT) of the change of spin density distribution within model [1-bpy(theta (1))](-) mono-reduced species as a function of theta (1) has been undertaken and the possibility of conformationally switching emission properties of P was derived.
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Affiliation(s)
- Philippe P Lainé
- Laboratoire de Chimie et Biochimie Pharmacologiques et Toxicologiques (CNRS UMR 8601), Université René Descartes, Paris, France.
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Goeb S, De Nicola A, Ziessel R. Oligomeric ligands incorporating multiple 5,5'-diethynyl-2,2'-bipyridine moieties bridged and end-capped by 3,4-dibutylthiophene units. J Org Chem 2005; 70:1518-29. [PMID: 15730269 DOI: 10.1021/jo048435i] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
In this work, we detail the synthesis and photophysical properties of a series of soluble polybipyridine ligands comprising one to five bipyridine units sandwiched between rigid carbon-carbon triple bonds substituted by 3,4-dibutylthiophene repeating units. The dual Sonogashira coupling reaction of 5,5'-dibromo-2,2'-bipyridine with TMS- and (CH3)2C(OH)-protected acetylene allows the synthesis of a dissymmetrically functionalized building block which was selectively deprotected at either the TMS or 2-hydroxyprop-2-yl site. Various combinations allow the interconnection of the terminal alkyne to 3,4-dibutyl-2,5-diiodothiophene or 3,4-dibutyl-2-iodothiophene leading to bipyridine frameworks bearing two acetylene-protected groups or one acetylenethiophene/one acetylene-protected function. It is possible therefore to construct dimeric to pentameric bipyridine ligands where the chelating subunit is bridged by a 3,4-dibutyl-2,5-diethynylthiophene spacer and end-capped by a 3,4-dibutyl-2-ethynylthiophene stopper. All cross-coupling reactions are promoted with palladium(0) tetrakistriphenylphosphine under mild conditions. Spectroscopic data for the new oligomers are discussed in terms of the extent of pi-electron conjugation. Upon increasing the number of pi-electrons from 24 to 104, there is a progressive lowering in the energy of absorption and fluorescence transitions, while the emission quantum yields remain essentially constant. The LUMO levels of these large molecules, estimated by cyclic voltammetry, lie in the range -3.06 to -3.18 eV.
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Affiliation(s)
- Sébastien Goeb
- Laboratoire de Chimie Moléculaire, Ecole de Chimie, Polymères, Matériaux (ECPM), Université Louis Pasteur (ULP), 25 rue Becquerel, 67087 Strasbourg Cedex 02, France
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32
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Cusumano M, Di Pietro ML, Giannetto A, Vainiglia PA. The intercalation to DNA of bipyridyl complexes of platinum(II) with thioureas. J Inorg Biochem 2005; 99:560-5. [PMID: 15621290 DOI: 10.1016/j.jinorgbio.2004.11.002] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2004] [Revised: 10/04/2004] [Accepted: 11/01/2004] [Indexed: 11/21/2022]
Abstract
The non-covalent interaction of the complexes [Pt(bpy)(R,R'NCSNR'',R''')(2)]Cl(2) (bpy=2,2'-bipyridine; R=R'=R''=R'''=H; R=Me, R'=R''=R'''=H; R=n-Bu, R'=R''=R'''=H; R=p-tolyl, R'=R''=R'''=H; R=Et, R'=H, R''=Et, R'''=H) with calf thymus DNA has been studied at pH 7 and 25 degrees C. The processes give rise to: (i) reversible bathochromic shifts and strong hypochromicity of the absorption bands of the complexes, (ii) induced circular dichroism and (iii) an increase both in the melting temperature and viscosity of the DNA comparable to that observed for other well known metallointercalators. The binding constants, K(B), have been determined spectrophotometrically using the McGhee von Hippel equation. Plot of logK(B) vs -log[Na(+)] for the complex with unsubstituted thiourea gives a straight line with a slope value close to that expected for a dicationic intercalator. The binding affinity of the various complexes for DNA is independent of the thiourea nature; this suggests that the intercalation occurs through stacking of the bpy moiety while the ancillary ligands lie outside the nucleobases far away from the sugar phosphate backbone. The data show also that the electronic effects of the ligand substituents are not transmitted to the intercalating unit.
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Affiliation(s)
- Matteo Cusumano
- Dipartimento di Chimica Inorganica, Chimica Analitica e Chimica Fisica, University of Messina, Salita Sperone 31, Vill. S. Agata, 98166 Messina, Italy.
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Siu J, Baxendale IR, Lewthwaite RA, Ley SV. A phase-switch purification approach for the expedient removal of tagged reagents and scavengers following their application in organic synthesis. Org Biomol Chem 2005; 3:3140-60. [PMID: 16106295 DOI: 10.1039/b503778f] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
In this paper we wish to report on a variety of expedient chemical transformations and purifications achieved via a generic "catch and release" methodology, based on a synthetically inert bipyridyl chelating tag that can be selectively captured with a resin-bound copper(II) species. Utilising this approach we are able to derive many of the same benefits associated with both solid phase synthesis and supported reagent methods.
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Affiliation(s)
- Jason Siu
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, UK
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34
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Abstract
The molecular expression of topologically interesting structures represents a formidable challenge for synthetic chemists. The nontrivial link known as the Borromean rings has long been regarded as one of the most ambitious targets in this field. Of ancient provenance, this symbol comprises three interlocked rings in an inseparable union, but cut any one of the rings and the whole assembly unravels into three separate pieces. This Account delineates different strategies that can be applied to the formation of molecules possessing this distinctive topology, culminating with two successful syntheses of such compounds, thus cutting the Gordian knot of topological chemistry.
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Affiliation(s)
- Stuart J Cantrill
- California NanoSystems Institute and Department of Chemistry and Biochemistry, University of California, Los Angeles, 405 Hilgard Avenue, Los Angeles, California 90095-1569, USA
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Borowicz P, Leś A, Adamowicz L, Waluk J. Vibrational spectroscopy of hydroxy-heterobiaryls. IR-active modes of [2,2′-bipyridyl]-3,3′-diol. Photochem Photobiol Sci 2005; 4:143-8. [PMID: 15616705 DOI: 10.1039/b410316e] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
All observed IR-active vibrational modes of [2,2'-bipyridyl]-3,3'-diol (BP(OH)2) and its two isotopomers, BP(OD)2 and BP(OH)2-d6 have been assigned on the basis of the comparison of experimental results with predictions obtained from DFT (B3LYP/6-31G(d,p)) calculations. The sensitivity of the vibrational transitions to the environment has been studied by comparing the spectra recorded in vapour, different solutions, KBr pellets, and cryogenic argon matrices. The results may be useful for the quantum control of excited state single or double proton transfer in BP(OH)2.
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Affiliation(s)
- Pawel Borowicz
- Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland
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Naumov P, Ohashi Y. Packing-dependent photochromism: the case of photoinduced intramolecular proton transfer in 6-(2′,4′-dinitrobenzyl)-2,2′-bipyridine. Acta Crystallogr B Struct Sci 2004; 60:343-9. [PMID: 15148438 DOI: 10.1107/s0108768104005506] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/17/2003] [Accepted: 03/09/2004] [Indexed: 11/10/2022]
Abstract
A new photoactive monoclinic polymorph (γ-form) of 6-(2′,4′-dinitrobenzyl)-2,2′-bipyridine was obtained from an acetone–methanol solution. The crystal structure was compared with those of two polymorphs reported previously (photoactive orthorhombic α-form and photoinactive monoclinic β-form) and with structures of related nitrobenzylpyridines to explain the relation between the structure and photochromism. The comparison of the reaction cavities around the reactive pyridyl–benzyl–nitro fragment among the polymorphs and related nitrobenzylpyridines revealed that a crucial factor for photochromic activity is the rotational freedom of the ortho-nitro group in their crystals and its accessibility from the proton–donor and proton–acceptor sites. This is because the ortho-nitro group should rotate around the N—C bond to transfer a proton from the methylene group to the N atom of the pyridine ring.
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Affiliation(s)
- Pance Naumov
- Department of Chemistry and Materials Science, Tokyo Institute of Technology, O-okayama, Meguro-ku, Tokyo 152-8551, Japan
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37
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Toma SH, Uemi M, Nikolaou S, Tomazela DM, Eberlin MN, Toma HE. {trans-1,4-Bis[(4-pyridyl)ethenyl]benzene}(2,2‘-bipyridine)ruthenium(II) Complexes and Their Supramolecular Assemblies with β-Cyclodextrin. Inorg Chem 2004; 43:3521-7. [PMID: 15154817 DOI: 10.1021/ic0352250] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Two novel ruthenium polypyridine complexes, [Ru(bpy)(2)Cl(BPEB)](PF(6)) and ([Ru(bpy)(2)Cl](2)(BPEB))(PF(6))(2) (BPEB = trans-1,4-bis[2-(4-pyridyl)ethenyl]benzene), were synthesized and their characterization carried out by means of elemental analysis, UV-visible spectroscopy, positive ion electrospray (ESI-MS), and tandem mass (ESI-MS/MS) spectrometry, as well as by NMR spectroscopy and cyclic voltammetry. Cyclic and differential pulse voltammetry for the mononuclear complex showed three set of waves around 1.2 V (Ru(2+/3+)), -1.0 V (BPEB(0/)(-)), and -1.15 (BPEB(-/2-)). This complex exhibited aggregation phenomena in aqueous solution, involving pi-pi stacking of the planar, hydrophobic BPEB ligands. According to NMR measurements and variable-temperature experiments, the addition of beta-cyclodextrin (betaCD) to [Ru(bpy)(2)Cl(BPEB)](+) leads to an inclusion complex, breaking down the aggregated array.
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Affiliation(s)
- Sergio H Toma
- Instituto de Química, Universidade de São Paulo USP, Caixa Postal 26077, CEP 05513, São Paulo, SP, Brazil
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Egan TJ, Koch KR, Swan PL, Clarkson C, Van Schalkwyk DA, Smith PJ. In Vitro Antimalarial Activity of a Series of Cationic 2,2‘-Bipyridyl- and 1,10-Phenanthrolineplatinum(II) Benzoylthiourea Complexes. J Med Chem 2004; 47:2926-34. [PMID: 15139771 DOI: 10.1021/jm031132g] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We have synthesized a series of novel 2,2'-bipyridyl and 1,10-phenanthroline benzoylthiourea complexes of platinum(II) with various substituents on the bipyridyl and phenanthroline ligands. All of these square-planar mixed-ligand cationic complexes were found to form moderately strong complexes with ferriprotoporphyrin IX in 40% aqueous DMSO (log K ranging from 4.81 to 6.24). The complexes also all inhibit beta-hematin (synthetic hemozoin or malaria pigment) formation in acetate solution. Four of the compounds were found to exhibit in vitro antimalarial activity, with (N-benzoyl-N',N'-di(2-hydroxyethyl)thioureato)(4,4'-di-tert-butyl-2,2'-bipyridyl)platinum(II) chloride being particularly active. These active complexes exhibited equally strong activity against both the D10 chloroquine sensitive and K1 chloroquine resistant strains of malaria parasite. Cytotoxicity testing of the four most active compounds shows that they exhibit selective activity against malaria parasites with selectivity indices greater than 85. These compounds represent a new family of potential antimalarials.
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Affiliation(s)
- Timothy J Egan
- Department of Chemistry, University of Cape Town, Private Bag, Rondebosch 7701, South Africa.
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Leroy-Lhez S, Parker A, Lapouyade P, Belin C, Ducasse L, Oberle J, Fages F. Tunable fluorescence emission in pyrene–(2,2′-bipyridine) dyads containing phenylene–ethynylene bridges. Photochem Photobiol Sci 2004; 3:949-59. [PMID: 15480486 DOI: 10.1039/b409250c] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A synthetic route is described for the preparation of a series of pyrene-containing pi-conjugated 2,2'-bipyridine (bpy) ligands. These compounds have been investigated by steady-state and time-resolved fluorescence spectroscopy. They display intense visible absorption and fluorescence emission properties that can be very efficiently modulated by the complexation of zinc(ii) metal ions to the bpy coordinating unit. The solvatochromism of the emission band of the zinc(ii) complexes, the fluorescence quantum yields, and lifetimes in THF have been determined. Zinc(ii)-induced formation of a charge transfer singlet excited states induces an increase in dipole moment of more than 20 D. Semiempirical theoretical calculations were performed and allowed to assess the electronic nature of ground and excited states of the free ligands and and that of the corresponding zinc(ii) complexes.
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Ryabov AD, Roznyatovskaya NV, Suwinska K, Revenco M, Ershov AY. Dinuclear versus mononuclear ruthenium(II) and osmium(II) complexes as potent mediators of glucose oxidase; crystal structure of [OsCl(4,4'-bpy)(bpy)2]BF4. J Biol Inorg Chem 2003; 8:815-22. [PMID: 12920611 DOI: 10.1007/s00775-003-0480-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2003] [Accepted: 06/19/2003] [Indexed: 11/25/2022]
Abstract
New and known homo- and heterodinuclear Ru(II) and Os(II) complexes with 4,4'-bipyridine (4,4'-bpy), pyrazine, and 4-pyCH=CHpy-4' as bridging ligands (LL) of the type [Cl(bpy)(2)M(LL)MCl(bpy)(2)]X(2) (bpy=2,2'-bipyridine; X=PF(6) or BF(4)) have been studied in their capacity to exchange electrons with a reduced active site of glucose oxidase (GO) from Aspergillus niger. Cyclic voltammograms (CVs) of the dimers in the aqueous buffered solution, when compared with CVs of the parent monomeric species [MCl(LL)(bpy)(2)]BF(4) and [MCl(2)(bpy)(2)] which could be generated at pH approximately 7, if the dimers undergo monomerization, indicate that the dimers are the dominating species under such conditions. All electrochemically oxidized dinuclear complexes studied show high rates of oxidation of GO reduced by D-glucose and the corresponding observed second-order rate constants are in the range (5-64)x10(5) M(-1) s(-1) at 25 degrees C. However, these values are lower than that for the mononuclear complex [OsCl(4,4'-bpy)(bpy)(2)]BF(4) (1.1x10(7) M(-1) s(-1)), suggesting that potentially two-electron dimeric mediators have no advantage compared with corresponding monomeric complexes of Ru(II) and Os(II). The structure of [OsCl(4,4'-bpy)(bpy)(2)]BF(4) was confirmed by X-ray crystallography. The monodentate 4,4'-bpy ligand is coordinated cis to the chloride. Its higher reactivity toward reduced GO is accounted for in terms of the antenna effect of the monodentate 4,4'-bpy ligand. The antenna length equals 9.2 A and matches the depth of the enzyme active site pocket of ca. 10 A. The mechanism of the antenna effect is discussed.
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Affiliation(s)
- Alexander D Ryabov
- Department of Chemistry, M.V. Lomonosov Moscow State University, 119899 Moscow, Russia.
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Abstract
[structure: see text] A dyad of eosin and tris(2,2'-bipyridine)Ru(II) was prepared, and its photophysical properties were investigated. The photosensitization of eosin is greatly enhanced by introduction of tris(2,2'-bipyridine)Ru(II), which is verified via photooxygenation of anthracene derivatives. The electron-transfer mechanism of photosensitization is also discussed.
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Affiliation(s)
- Bingwen Jing
- Center for Molecular Science, Institute of Chemstry, Chinese Academy of Sciences, Beijing 100080, P. R. China
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Hasegawa T, Yonemura T, Matsuura K, Kobayashi K. Artificial metalloglycoclusters: compact saccharide shell to induce high lectin affinity as well as strong luminescence. Bioconjug Chem 2003; 14:728-37. [PMID: 12862425 DOI: 10.1021/bc020026a] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Tris-bipyridine ferrous and ruthenium complexes carrying various saccharide appendages have been investigated to develop sensory systems for monitoring saccharide-binding phenomena. Ferrous O-glycoclusters having spacer moieties inserted between saccharide appendages and the complex core showed enhanced affinities to lectins, but ferrous N-glycoclusters, in which the saccharide-appendages are directly linked to the complex core via amide linkage, had low lectin-affinities. Molecular dynamics calculation indicated that the O-glycoclusters have flexible and densely packed saccharide clusters, in contrast to the octahedrally fixed saccharide arrays of N-glycoclusters. Flexibility of saccharide clusters is essential for their enhanced affinity, probably to induce conformational change to fit the recognition sites of lectins. According to these insights, ruthenium O-glycoclusters have been designed as luminescence biosensors. The ruthenium complexes carrying alpha-manno clusters exhibited excellent affinities (IC(min) = 9.0 x 10(-)(8) M) to concanavalin A (ConA). It is suggested from conformational analysis that densely packed mannoclusters can be fit properly to the recognition site of ConA. The binding was enthalpicaly driven (deltaH degrees = -21.8 kcal/mol). This binding behavior is quite similar to that of 1-3/1-6 trimannoside to ConA. They have strongly amplified luminescence (Phi(em) = 0.15), and their luminescence intensities were changed (approximately 40%) upon binding to the specific lectins. The ruthenium glycoclusters can be a suitable sensory system for saccharide-binding phenomena.
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Affiliation(s)
- Teruaki Hasegawa
- Department of Molecular Design, Graduate School of Engineering, Nagoya University, Chikusa, Nagoya 464-8603, Japan
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Cheng KF, Drain CM, Grohmann K. Porphyrins linked directly to the 5,5' positions of 2,2'-bipyridine: a new supramolecular building block and switch. Inorg Chem 2003; 42:2075-83. [PMID: 12639144 DOI: 10.1021/ic025985v] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The synthesis and coordination chemistry of two porphyrin dimers linked either at the 5,5' or the 4,4' positions of 2,2'-bipyridine are described. These compounds, which may serve a molecular tectons for the constructions of a variety of supramolecular arrays of diverse function, reveal that the ground- and excited-state electronic communication between the chromophores is only moderately affected by the complexation state of the bipyridyl moiety. The nature of the metal ion chelated by the bipyridine only slightly perturbs the ground-state spectra, and differences observed in the excited state are largely ascribed to the heavy atom effect. This work also shows that conformational changes in structural subunits, in this case induced by bipyridyl complexation of various metal ions, do not necessarily require reorganization of supramolecular systems.
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Affiliation(s)
- Kai Fan Cheng
- Department of Chemistry and Biochemistry, Hunter College and Graduate Center of the City University of New York, 695 Park Avenue, New York, New York 10021, USA
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Abstract
The (1,3,6-trioxa-heptyl) aromatic compounds are easily prepared from various phenols and hydroxypyridines. Protection by 2-methoxyethoxymethyl chloride (MEM-Cl) was achieved by phase transfer catalysis with Aliquat 336, subsequent removal of the protecting group was completed with Amberlyst 15. The 2-bromo-3-hydroxy-pyridine 3o constitutes the appropriate starting material for the synthesis of orellanine, the most potent nephrotoxin found in some Cortinarius mushrooms species.
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Affiliation(s)
- Didier Michelot
- Laboratoire de Chimie des Substances Naturelles, ESA 8041 CNRS, Muséum National d'Histoire Naturelle, 63, rue de Buffon, F-75005 Paris, France.
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45
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Abstract
The synthesis and conformational behavior of two cyclodextrin dimers containing aromatic bipyridine spacers is presented. The proton NMR spectra of these dimers in aqueous solution show a doubling of signals in the aromatic region due to complete or partial self-inclusion of the spacer. The degree and the strength of self-inclusion is dependent on the substitution pattern of the bipyridine unit. This unexpected difference in the self-inclusion behavior is revealed by 2D NOESY and circular dichroism spectra.
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Affiliation(s)
- Hubertus F M Nelissen
- Department of Organic Chemistry, Nijmegen Science Research Institute of Matter, University of Nijmegen, Toernooiveld 1, 6525 ED Nijmegen, The Netherlands
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46
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Abstract
[reaction: see text] Bright green boradiazaindacene fluorescence is quenched by an oxidative photoinduced electron transfer (PET) from the excited state fluorophore to the bipyridyl unit complexed to metal cations. The closed shell diamagnetic cation Zn(II) is one of the most effective quenchers of fluorescence in this system, demonstrating that the quenching is not simply related to the facilitated intersystem crossing. The molecule also acts as a NOR logic gate with two chemical inputs, TFA and Zn(II).
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Affiliation(s)
- Bilge Turfan
- Department of Chemistry, Middle East Technical University, Ankara TR-06531, Turkey
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47
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Abstract
[reaction: see text] The total synthesis of caerulomycin C is described. Key steps in this synthesis utilize 1,2-, 1,3-, and 1,4-halogen dance reactions for the functionalization of the pyridine ring.
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Affiliation(s)
- Tarek Sammakia
- Department of Chemistry and Biochemistry, University of Colorado, Boulder, Colorado 80309-0215, USA.
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48
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Elgemeie GH, El-Enany MM, Ismail MM, Ahmed EK. Nucleic acid components and their analogues: a novel and efficient method for the synthesis of a new class of bipyridyl and biheterocyclic-nitrogen thioglycosides from pyridine-2(1H)-thiones. Nucleosides Nucleotides Nucleic Acids 2002; 21:477-93. [PMID: 12442965 DOI: 10.1081/ncn-120014820] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
A novel synthesis of a new class of bipyridyl and biheterocyclic-nitrogen thioglycosides utilizing the reactions of heterocyclic substituted pyridine-2(1H)-thiones and alpha-bromoglucose or alpha-bromogalactose tetraacetate as starting components is described.
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Affiliation(s)
- Galal H Elgemeie
- Chemistry Department, Faculty of Science, Helwan University, Ain-Helwan, Cairo, Egypt.
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49
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Charbonnière LJ, Weibel N, Ziessel RF. 5'-substituted-6-carboxylic-2,2'-bipyridine acid: a pivotal architecton for building preorganized ligands. J Org Chem 2002; 67:3933-6. [PMID: 12027719 DOI: 10.1021/jo0200015] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
A set of ligands bearing 6-bromo-2,2'-bipyridine pendant arms attached in the 5'-position are described. Transformation of the bromo to an ester was performed by a carboethoxylation reaction promoted by low-valent Pd(0), while saponification followed by acidification gave the acids. The introduction of an appended function 3-nitrobenzyl, benzamidomethyl, and tert-butylacetyl opens the way to further functionalize these scaffolds for potential labeling of biological material. The synthetic protocols represent a valuable approach to the rational design of ligands bearing oxophilic and anionic sidearms.
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Affiliation(s)
- Loïc J Charbonnière
- Laboratoire de Chimie Moléculaire, Associé au CNRS UMR-7008, Ecole de Chimie, Polymères et Matériaux de Strasbourg (ECPM), 25 rue Becquerel, 67087 Strasbourg Cedex 02, France
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50
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Abstract
Caerulomycins produced by Streptomyces caeruleus are bipyridinic molecules endowed with antibiotic properties. The first synthesis of caerulomycin B (1) as well as a new synthesis of caerulomycin C (2) are reported. Starting from 3-hydroxypyridine, the same methodology was used to prepare both compounds 1 and 2. Efficiently controlled reactions such as metalation to allow the synthesis of 2,6-diiodo-3,4-dialkoxypyridines, which are key intermediates, and further halogen-lithium exchange and cross-coupling to reach the targets molecules 1 and 2 have been developed.
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Affiliation(s)
- Florence Mongin
- Laboratoire de Chimie Organique Fine et Hétérocyclique, IRCOF, UMR 6014, Place E. Blondel, BP 08, 76131 Mont-Saint-Aignan Cédex, France
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