101
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Redmond MP, Cornet SM, Woodall SD, Whittaker D, Collison D, Helliwell M, Natrajan LS. Probing the local coordination environment and nuclearity of uranyl(vi) complexes in non-aqueous media by emission spectroscopy. Dalton Trans 2011; 40:3914-26. [DOI: 10.1039/c0dt01464h] [Citation(s) in RCA: 80] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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102
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Lancashire HN, Brown NJ, Carthy L, Collison D, Fitzgerald EC, Edge R, Helliwell M, Holden M, Low PJ, McDouall JJW, Whiteley MW. Synthesis, spectroscopy and electronic structure of the vinylidene and alkynyl complexes [W(CCHR)(dppe)(η-C7H7)]+and [W(CCR)(dppe)(η-C7H7)]n+(n = 0 or 1). Dalton Trans 2011; 40:1267-78. [DOI: 10.1039/c0dt01150a] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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103
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Sharples JW, Zheng YZ, Tuna F, McInnes EJL, Collison D. Lanthanide discs chill well and relax slowly. Chem Commun (Camb) 2011; 47:7650-2. [DOI: 10.1039/c1cc12252e] [Citation(s) in RCA: 238] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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104
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Brown NJ, Lancashire HN, Fox MA, Collison D, Edge R, Yufit DS, Howard JAK, Whiteley MW, Low PJ. Molybdenum Complexes of C,C-Bis(ethynyl)carboranes: Design, Synthesis, and Study of a Weakly Coupled Mixed-Valence Compound. Organometallics 2010. [DOI: 10.1021/om1010353] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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105
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Berthon C, Boubals N, Charushnikova IA, Collison D, Cornet SM, Den Auwer C, Gaunt AJ, Kaltsoyannis N, May I, Petit S, Redmond MP, Reilly SD, Scott BL. The Reaction Chemistry of Plutonyl(VI) Chloride Complexes with Triphenyl Phosphineoxide and Triphenyl Phosphinimine. Inorg Chem 2010; 49:9554-62. [DOI: 10.1021/ic101251a] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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106
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Smith DA, Batsanov AS, Costuas K, Edge R, Apperley DC, Collison D, Halet JF, Howard JAK, Dyer PW. Exploiting Non-Innocent Ligands to Prepare Masked Palladium(0) Complexes. Angew Chem Int Ed Engl 2010; 49:7040-4. [DOI: 10.1002/anie.201003946] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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107
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Smith DA, Batsanov AS, Costuas K, Edge R, Apperley DC, Collison D, Halet JF, Howard JAK, Dyer PW. Exploiting Non-Innocent Ligands to Prepare Masked Palladium(0) Complexes. Angew Chem Int Ed Engl 2010. [DOI: 10.1002/ange.201003946] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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108
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Jones MD, Cooper CJ, Mahon MF, Raithby PR, Apperley D, Wolowska J, Collison D. Cu(II) homogeneous and heterogeneous catalysts for the asymmetric Henry reaction. ACTA ACUST UNITED AC 2010. [DOI: 10.1016/j.molcata.2010.03.013] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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109
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Aigbirhio FI, Allen J, Arrowsmith RL, Athlan A, Badman GT, Bayly SR, Bedford R, Botting NP, Bragg RA, Brasseur D, Bushby N, Cable KM, Chan F, Christlieb M, Churchill GC, Collison D, Denoux M, Dilworth JR, Farrar G, Gotfredsen CH, Greaney MF, Harding JR, Harris P, Harwood SJ, Heglund IF, Hendry D, Hosseini M, Johnston JS, Jones S, Jordan A, Killick DA, Kitson SL, Kowalczyk RM, Lawrie KWM, Lockley WJS, Madge D, Manning C, Marshall LJ, McNeill AH, Newman JJ, Pascu SI, Roy S, Schofield J, Shanmugham MS, Shipley NJ, Simmonds AJ, Smith D, Smith SL, Steward OR, Tanner D, Travers JG, Tyrrell RM, Vital P, Waghorn PA, Warrington B, Watters W, Willcocks K, Williams GD, Young CG, Zhong J. Abstracts of the 18th international isotope society (UK group) symposium: synthesis & applications of labelled compounds 2009. J Labelled Comp Radiopharm 2010. [DOI: 10.1002/jlcr.1751] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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110
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Magnani N, Colineau E, Eloirdi R, Griveau JC, Caciuffo R, Cornet SM, May I, Sharrad CA, Collison D, Winpenny REP. Superexchange coupling and slow magnetic relaxation in a transuranium polymetallic complex. PHYSICAL REVIEW LETTERS 2010; 104:197202. [PMID: 20866994 DOI: 10.1103/physrevlett.104.197202] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2010] [Indexed: 05/29/2023]
Abstract
{Np(VI)O2Cl2}{Np(V)O2Cl(thf)3}2 is the first studied example of a polymetallic transuranic complex displaying both slow relaxation of the magnetization and effective superexchange interactions between 5f centers. The coupling constant for Np(V)-Np(VI) pairs is 10.8 K, more than 1 order of magnitude larger than the common values found for rare-earth ions in similar environments. The dynamic magnetic behavior displays slow relaxation of magnetization of molecular origin with an energy barrier of 140 K, which is nearly twice the size of the highest barrier found in polymetallic clusters of the d block. Our observations also suggest that future actinide-based molecular magnets will have very different behavior to lanthanide-based clusters.
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111
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Layfield R, McDouall JJ, Sulway S, Tuna F, Collison D, Winpenny RE. Influence of the N-Bridging Ligand on Magnetic Relaxation in an Organometallic Dysprosium Single-Molecule Magnet. Chemistry 2010; 16:4442-6. [DOI: 10.1002/chem.201000158] [Citation(s) in RCA: 208] [Impact Index Per Article: 14.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2010] [Indexed: 11/12/2022]
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112
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Brown NJ, Collison D, Edge R, Fitzgerald EC, Helliwell M, Howard JAK, Lancashire HN, Low PJ, McDouall JJW, Raftery J, Smith CA, Yufit DS, Whiteley MW. Spectroscopic Properties and Electronic Structure of the Cycloheptatrienyl Molybdenum Alkynyl Complexes [Mo(C≡CR)(Ph2PCH2CH2PPh2)(η-C7H7)]n+(n= 0 or 1; R =But, Fc, CO2Me, or C6H4-4-X, X = NH2, OMe, Me, H, CHO, CO2Me). Organometallics 2010. [DOI: 10.1021/om901074b] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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113
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Pascu S, Waghorn P, Kennedy B, Arrowsmith R, Bayly S, Dilworth J, Christlieb M, Tyrrell R, Zhong J, Kowalczyk R, Collison D, Aley P, Churchill G, Aigbirhio F. Fluorescent Copper(II) Bis(thiosemicarbazonates): Synthesis, Structures, Electron Paramagnetic Resonance, Radiolabeling, In Vitro Cytotoxicity and Confocal Fluorescence Microscopy Studies. Chem Asian J 2010; 5:506-19. [DOI: 10.1002/asia.200900446] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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114
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Carter E, Collison D, Edge R, Fitzgerald EC, Lancashire HN, Murphy DM, McDouall JJW, Sharples J, Whiteley MW. Experimental observation of spin delocalisation onto the aryl-alkynyl ligand in the complexes [Mo(CCAr)(Ph2PCH2CH2PPh2)(η-C7H7)]+ (Ar = C6H5, C6H4-4-F; C7H7 = cycloheptatrienyl): an EPR and ENDOR investigation. Dalton Trans 2010; 39:11424-31. [DOI: 10.1039/c0dt00642d] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
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115
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Brown NJ, Collison D, Edge R, Fitzgerald EC, Low PJ, Helliwell M, Ta YT, Whiteley MW. Metal-stabilised diynyl radicals: structure and reactivity of [Mo(CC–CCSiMe3)L2(η-C7H7)]˙+ (L2 = 2,2′-bipyridine or dppe). Chem Commun (Camb) 2010; 46:2253-5. [DOI: 10.1039/b924759a] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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116
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Scales E, Sorace L, Dei A, Caneschi A, Muryn CA, Collison D, McInnes EJL. Low-valent vanadium catecholate clusters. Chem Sci 2010. [DOI: 10.1039/c0sc00142b] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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117
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Boeer A, Collison D, Muryn C, Timco G, Tuna F, Winpenny R. Linkage Isomerism and Spin Frustration in Heterometallic Rings: Synthesis, Structural Characterization, and Magnetic and EPR Spectroscopic Studies of Cr7Ni, Cr6Ni2, and Cr7Ni2Rings Templated About Imidazolium Cations. Chemistry 2009; 15:13150-60. [DOI: 10.1002/chem.200901938] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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118
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Guimond SE, Rudd TR, Skidmore MA, Ori A, Gaudesi D, Cosentino C, Guerrini M, Edge R, Collison D, McInnes E, Torri G, Turnbull JE, Fernig DG, Yates EA. Cations modulate polysaccharide structure to determine FGF-FGFR signaling: a comparison of signaling and inhibitory polysaccharide interactions with FGF-1 in solution. Biochemistry 2009; 48:4772-9. [PMID: 19400583 DOI: 10.1021/bi802318z] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
For heparan sulfate (HS) to bind and regulate the activity of proteins, the polysaccharide must present an appropriate sequence and adopt a suitable conformation. The conformations of heparin derivatives, as models of HS, are altered via a change in the associated cations, and this can drastically modify their FGF signaling activities. Here, we report that changing the cations associated with an N-acetyl-enriched heparin polysaccharide, from sodium to copper(II), converted it from supporting signaling through the fibroblast growth factor receptor (FGF-1-FGFR1c) tyrosine kinase signaling system to being inhibitory in a cell-based BaF3 assay. Nuclear magnetic resonance and synchrotron radiation circular dichroism (SRCD) spectroscopy demonstrated that the polysaccharide conformation differed in the presence of sodium or copper(II) cations. Electron paramagnetic resonance confirmed the environment of the copper(II) ion on the N-acetyl-enriched polysaccharide was distinct from that previously observed with intact heparin, which supported signaling. Secondary structures in solution complexes of polysaccharides with FGF-1 (which either supported signaling through FGFR1c or were inhibitory) were determined by SRCD. This allowed direct comparison of the two FGF-1-polysaccharide complexes in solution, containing identical molecular components and differing only in their cation content. Subtle structural differences were revealed, including a reduction in the level of disordered structure in the inhibitory complex.
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119
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Collison D. Advanced structural inorganic chemistry, by Wai-Kee Li, Gong-Du Zhou and Thomas Chung Wai Mak. CRYSTALLOGR REV 2009. [DOI: 10.1080/08893110902731967] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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120
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Piligkos S, Weihe H, Bill E, Neese F, El Mkami H, Smith G, Collison D, Rajaraman G, Timco G, Winpenny R, McInnes E. EPR Spectroscopy of a Family of CrIII7MII(M = Cd, Zn, Mn, Ni) “Wheels”: Studies of Isostructural Compounds with Different Spin Ground States. Chemistry 2009; 15:3152-67. [DOI: 10.1002/chem.200801895] [Citation(s) in RCA: 72] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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121
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Cornet SM, Häller LJL, Sarsfield MJ, Collison D, Helliwell M, May I, Kaltsoyannis N. Neptunium(vi) chain and neptunium(vi/v) mixed valence cluster complexes. Chem Commun (Camb) 2009:917-9. [DOI: 10.1039/b818973k] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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122
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Copping R, Talbot-Eeckelaers C, Collison D, Helliwell M, Gaunt AJ, May I, Reilly SD, Scott BL, McDonald RD, Valenzula OA, Jones CJ, Sarsfield MJ. Probing the 5f electrons in a plutonyl(vi) cluster complex. Dalton Trans 2009:5609-11. [DOI: 10.1039/b908648j] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
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123
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Holland JP, Barnard PJ, Collison D, Dilworth JR, Edge R, Green JC, McInnes EJL. Spectroelectrochemical and computational studies on the mechanism of hypoxia selectivity of copper radiopharmaceuticals. Chemistry 2008; 14:5890-907. [PMID: 18494010 DOI: 10.1002/chem.200800539] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Detailed chemical, spectroelectrochemical and computational studies have been used to investigate the mechanism of hypoxia selectivity of a range of copper radiopharmaceuticals. A revised mechanism involving a delicate balance between cellular uptake, intracellular reduction, reoxidation, protonation and ligand dissociation is proposed. This mechanism accounts for observed differences in the reported cellular uptake and washout of related copper bis(thiosemicarbazonato) complexes. Three copper and zinc complexes have been characterised by X-ray crystallography and the redox chemistry of a series of copper complexes has been investigated by using electronic absorption and EPR spectroelectrochemistry. Time-dependent density functional theory (TD-DFT) calculations have also been used to probe the electronic structures of intermediate species and assign the electronic absorption spectra. DFT calculations also show that one-electron oxidation is ligand-based, leading to the formation of cationic triplet species. In the absence of protons, metal-centred one-electron reduction gives the reduced anionic copper(I) species, [CuIATSM](-), and for the first time it is shown that molecular oxygen can reoxidise this anion to give the neutral, lipophilic parent complexes, which can wash out of cells. The electrochemistry is pH dependent and in the presence of stronger acids both chemical and electrochemical reduction leads to quantitative and rapid dissociation of copper(I) ions from the mono- or diprotonated complexes, [CuIATSMH] and [Cu(I)ATSMH2]+. In addition, a range of protonated intermediate species have been identified at lower acid concentrations. The one-electron reduction potential, rate of reoxidation of the copper(I) anionic species and ease of protonation are dependent on the structure of the ligand, which also governs their observed behaviour in vivo.
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124
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Holland JP, Barnard PJ, Collison D, Dilworth JR, Edge R, Green JC, Heslop JM, McInnes EJL, Salzmann CG, Thompson AL. Synthesis, X‐ray Crystallography, Spectroelectrochemistry and Computational Studies on Potential Copper‐Based Radiopharmaceuticals. Eur J Inorg Chem 2008. [DOI: 10.1002/ejic.200800413] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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125
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Copping R, Jonasson L, Gaunt AJ, Drennan D, Collison D, Helliwell M, Pirttijarvi RJ, Jones CJ, Huguet A, Apperley DC, Kaltsoyannis N, May I. Tetravalent Metal Complexation by Keggin and Lacunary Phosphomolybdate Anions. Inorg Chem 2008; 47:5787-98. [DOI: 10.1021/ic800101t] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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