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Tomczyk MD, Kuźnik N, Walczak K. Cyclen-based artificial nucleases: Three decades of development (1989–2022). Part a – Hydrolysis of phosphate esters. Coord Chem Rev 2023. [DOI: 10.1016/j.ccr.2023.215047] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/10/2023]
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2
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Fanning AM, Plush SE, Gunnlaugsson T. Tri- and tetra-substituted cyclen based lanthanide(III) ion complexes as ribonuclease mimics: a study into the effect of log Ka, hydration and hydrophobicity on phosphodiester hydrolysis of the RNA-model 2-hydroxypropyl-4-nitrophenyl phosphate (HPNP). Org Biomol Chem 2016; 13:5804-16. [PMID: 25909178 DOI: 10.1039/c4ob02384f] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
A series of tetra-substituted 'pseudo' dipeptide ligands of cyclen (1,4,7,10,-tetraazacyclododecane) and a tri-substituted 3'-pyridine ligand of cyclen, and the corresponding lanthanide(III) complexes were synthesised and characterised as metallo-ribonuclease mimics. All complexes were shown to promote hydrolysis of the phosphodiester bond of 2-hydroxypropyl-4-nitrophenyl phosphate (HPNP, τ1/2 = 5.87 × 10(3) h), a well known RNA mimic. The La(III) and Eu(III) tri-substituted 3'-pyridine lanthanide(III) complexes being the most efficient in promoting such hydrolysis at pH 7.4 and at 37 °C; with τ1/2 = 1.67 h for La(III) and 1.74 h for Eu(III). The series was developed to provide the opportunity to investigate the consequences of altering the lanthanide(III) ion, coordination ability and hydrophobicity of a metallo-cavity on the rate of hydrolysis using the model phosphodiester, HPNP, at 37 °C. To further provide information on the role that the log Ka of the metal bound water plays in phosphodiester hydrolysis the protonation constants and the metal ion stability constants of both a tri and tetra-substituted 3'pyridine complex were determined. Our results highlighted several key features for the design of lanthanide(III) ribonucelase mimics; the presence of two metal bound water molecules are vital for pH dependent rate constants for Eu(III) complexes, optimal pH activity approximating physiological pH (∼7.4) may be achieved if the log Ka values for both MLOH and ML(OH)2 species occur in this region, small changes to hydrophobicity within the metallo cavity influence the rate of hydrolysis greatly and an amide adjacent to the metal ion capable of forming hydrogen bonds with the substrate is required for achieving fast hydrolysis.
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Affiliation(s)
- Ann-Marie Fanning
- School of Chemistry and Trinity Biomedical Sciences Institute, University of Dublin, Trinity College Dublin, Dublin 2, Ireland.
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Pautus S, Sehr P, Lewis J, Fortuné A, Wolkerstorfer A, Szolar O, Guilligay D, Lunardi T, Décout JL, Cusack S. New 7-methylguanine derivatives targeting the influenza polymerase PB2 cap-binding domain. J Med Chem 2013; 56:8915-30. [PMID: 24134208 DOI: 10.1021/jm401369y] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
The heterotrimeric influenza virus polymerase performs replication and transcription of viral RNA in the nucleus of infected cells. Transcription by "cap-snatching" requires that host-cell pre-mRNAs are bound via their 5' cap to the PB2 subunit. Thus, the PB2 cap-binding site is potentially a good target for new antiviral drugs that will directly inhibit viral replication. Docking studies using the structure of the PB2 cap-binding domain suggested that 7-alkylguanine derivatives substituted at position N-9 and N-2 could be good candidates. Four series of 7,9-di- and 2,7,9-trialkyl guanine derivatives were synthesized and evaluated by an AlphaScreen assay in competition with a biotinylated cap analogue. Three synthesized compounds display potent in vitro activity with IC50 values lower than 10 μM. High-resolution X-ray structures of three inhibitors in complex with the H5N1 PB2 cap-binding domain confirmed the binding mode and provide detailed information for further compound optimization.
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Affiliation(s)
- Stéphane Pautus
- Département de Pharmacochimie Moléculaire, Université de Grenoble Alpes/CNRS, UMR 5063 , ICMG FR 2607, 470 rue de la Chimie, BP 53, F-38041 Grenoble, France
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4
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Gunnlaugsson T, Harte AJ, Leonard JP, Nieuwenhuyzen M. The Formation of Luminescent Supramolecular Ternary Complexes in Water: Delayed Luminescence Sensing of Aromatic Carboxylates Using Coordinated Unsaturated Cationic Heptadentate Lanthanide Ion Complexes. Supramol Chem 2011. [DOI: 10.1080/10610270310001605106] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Affiliation(s)
| | - Andrew J. Harte
- a Department of Chemistry , Trinity College Dublin, 2, Dublin, Ireland
| | - Joseph P. Leonard
- a Department of Chemistry , Trinity College Dublin, 2, Dublin, Ireland
| | - Mark Nieuwenhuyzen
- b School of Chemistry , Queen's University of Belfast , BTAG, 9 5, Belfast, UK
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Carney CE, Tran AD, Wang J, Schabel MC, Sherry AD, Woods M. Towards the rational design of MRI contrast agents: δ-substitution of lanthanide(III) NB-DOTA-tetraamide chelates influences but does not control coordination geometry. Chemistry 2011; 17:10372-8. [PMID: 21837722 DOI: 10.1002/chem.201101007] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2011] [Indexed: 11/12/2022]
Abstract
LnDOTA-tetraamide chelates (DOTA=1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid) have received considerable recent attention as a result of their potential to act as PARACEST contrast agents for magnetic resonance imaging (MRI). Although PARACEST agents afford several advantages over conventional contrast agents they suffer from substantially higher detection limits; thus, improving the effectiveness of LnDOTA-tetraamide chelates is an important goal. In this study we investigate the potential to extend conformational control of LnDOTA-type ligands to those applicable to PARACEST. Furthermore, the question of whether δ- rather than α-substitution of the pendant arms could be used to control the chelate coordination geometry is addressed. Although δ-substitution does influence coordination geometry it does not afford control. However, it can play an important role in governing the conformation of the amide substituent relative to the chelate in such as way that suggests a PARACEST agent could be designed that has detection limits at least as low as a conventional MRI contrast agent.
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Affiliation(s)
- Christiane E Carney
- Department of Chemistry, Portland State University, 1719 SW 10th Ave, Portland, OR 97201, USA
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Mani T, Tircsó G, Zhao P, Sherry AD, Woods M. Effect of the regiochemistry of butyl amide substituents on the solution-state structures of lanthanide(III) DOTA-tetraamide complexes. Inorg Chem 2010; 48:10338-45. [PMID: 19799440 DOI: 10.1021/ic9017008] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The coordination geometry adopted by the lanthanide complexes of DOTA-tetraamides is a critical factor in determining their water exchange kinetics. Controlling the water exchange kinetics of DOTA-tetraamide complexes, and by extension their coordination geometry, is of particular interest because of the potential application of this class of complex as PARACEST MRI contrast agents. To facilitate the maximum CEST effect at the lowest pre-saturation powers much slower exchange kinetics are required than are commonly observed with these types of chelates. Complexes that adopt the more slowly exchanging square antiprismatic coordination geometry are therefore preferred; however, the factors that govern which coordination geometry is preferred remain unclear. A series of DOTA-tetraamide complexes with butyl amide substituents in different regioisomeric configurations provides some insight into these factors. The population of each coordination geometry was found to vary substantially depending upon the regiochemistry of the butyl amide substituent. It was observed that the twisted square antiprism coordination geometry, usually favored in complexes with the larger lanthanide ions only, is also increasingly favored for certain DOTA-tetraamide complexes with the smaller lanthanides. This is in marked contrast to simple DOTA-tetraamide complexes such as DOTAM. The effect was more prevalent in complexes formed with more bulky and more electron donating amide butyl substituents. It is also associated with loss of an inner-sphere water molecule from the complexes of later lanthanides that adopt the twisted square antiprismatic geometry. The complexes with sec-butyl substituents are inherently more complicated because of the introduction of a stereochemical center into each pendant arm. Unlike chiral complexes with larger amide substituents there is no "locking" effect of the orientation of the pendant arms in these complexes and up to four diastereoisomeric coordination isomers can be observed.
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Affiliation(s)
- Tomoyasu Mani
- Department of Chemistry, University of Texas at Dallas, 800 W. Campbell Road, Richardson, Texas 75080, USA
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7
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Plush SE, Clear NA, Leonard JP, Fanning AM, Gunnlaugsson T. The effect on the lanthanide luminescence of structurally simple Eu(iii) cyclen complexes upon deprotonation of metal bound water molecules and amide based pendant arms. Dalton Trans 2010; 39:3644-52. [DOI: 10.1039/b923383k] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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8
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Belousoff MJ, Ung P, Forsyth CM, Tor Y, Spiccia L, Graham B. New macrocyclic terbium(III) complex for use in RNA footprinting experiments. J Am Chem Soc 2009; 131:1106-14. [PMID: 19119812 PMCID: PMC2633772 DOI: 10.1021/ja807301r] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Reaction of terbium triflate with a heptadentate ligand derivative of cyclen, L1 = 2-[7-ethyl-4,10-bis(isopropylcarbamoylmethyl)-1,4,7,10-tetraazacyclododec-1-yl]-N-isopropyl-acetamide, produced a new synthetic ribonuclease, [Tb(L1)(OTf)(OH(2))](OTf)(2).MeCN (C1). X-ray crystal structure analysis indicates that the terbium(III) center in C1 is 9-coordinate, with a capped square-antiprism geometry. While the terbium(III) center is tightly bound by the L1 ligand, two of the coordination sites are occupied by labile water and triflate ligands. In water, the triflate ligand is likely to be displaced, forming [Tb(L1)(OH(2))(2)](3+), which is able to effectively promote RNA cleavage. This complex greatly accelerates the rate of intramolecular transesterification of an activated model RNA phosphodiester, uridine-3'-p-nitrophenylphosphate (UpNP), with k(obs) = 5.5(1) x 10(-2) s(-1) at 21 degrees C and pH 7.5, corresponding to an apparent second-order rate constant of 277(5) M(-1) s(-1). By contrast, the analogous complex of an octadentate derivative of cyclen featuring only a single labile coordination site, [Tb(L2)(OH(2))](OTf)(3) (C2), where L2 = 2-[4,7,10-tris(isopropylcarbamoylmethyl)-1,4,7,10-tetraazacyclododec-1-yl]-N-isopropyl-acetamide, is inactive. [Tb(L1)(OH(2))(2)](3+) is also capable of hydrolyzing short transcripts of the HIV-1 transactivation response (TAR) element, HIV-1 dimerization initiation site (DIS) and ribosomal A-site, as well as formyl methionine tRNA (tRNA(fMet)), albeit at a considerably slower rate than UpNP transesterification (k(obs) = 2.78(8) x 10(-5) s(-1) for TAR cleavage at 37 degrees C, pH 6.5, corresponding to an apparent second-order rate constant of 0.56(2) M(-1)s(-1)). Cleavage is concentrated at the single-stranded "bulge" regions of these RNA motifs. Exploiting this selectivity, [Tb(L1)(OH(2))(2)](3+) was successfully employed in footprinting experiments, in which binding of the Tat peptide and neomycin B to the bulge region of the TAR stem-loop was confirmed.
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Affiliation(s)
- Matthew J. Belousoff
- School of Chemistry, Monash University, Clayton, Vic 3800, Australia
- Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, CA 92093-0358, USA
| | - Phuc Ung
- Medicinal Chemistry and Drug Action, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Vic 3052, Australia
| | - Craig M. Forsyth
- School of Chemistry, Monash University, Clayton, Vic 3800, Australia
| | - Yitzhak Tor
- Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, CA 92093-0358, USA
| | - Leone Spiccia
- School of Chemistry, Monash University, Clayton, Vic 3800, Australia
| | - Bim Graham
- Medicinal Chemistry and Drug Action, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Vic 3052, Australia
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Skwierawska A, Paluszkiewicz E, Przyborowska M, Ossowski T. 1,4,7,10-Tetraazacyclododecane incorporating salicylic acid moieties synthesis and properties. J INCL PHENOM MACRO 2008. [DOI: 10.1007/s10847-008-9423-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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10
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Ruiz-Martínez A, Casanova D, Alvarez S. Polyhedral structures with an odd number of vertices: nine-coordinate metal compounds. Chemistry 2008; 14:1291-303. [PMID: 18000919 DOI: 10.1002/chem.200701137] [Citation(s) in RCA: 253] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The stereochemistry of nine-coordinate transition-metal and rare-earth compounds has been studied by means of continuous shape measures (CShM) and related tools. Several reference nine-vertex polyhedra have been defined and their minimal distortion interconversion paths established. A theoretical shape map is presented in which the structures can be placed according to their distances in CShM space to the capped square antiprism and the tricapped trigonal prism, which are the most common polyhedra in nine-coordinate compounds. The structures of almost 2000 metal coordination spheres in molecular and extended solid-state compounds have been analyzed. Clear stereochemical trends can be established for subsets of these compounds grouped according to the nature of their ligands, which include families of compounds spread along the interconversion paths between the capped square antiprism and the capped cube, or between the tricapped trigonal prism and the tridiminished icosahedron.
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Affiliation(s)
- Antonio Ruiz-Martínez
- Departament de Química Inorgànica and Institut de Química Teòrica i Computacional, Universitat de Barcelona, Martí i Franqués 1-11, 08028 Barcelona, Spain
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Luo Y, Lin H, Lin H. Kinetics and mechanism of promoted hydrolysis of 2-hydroxypropyl-p-nitrophenyl phosphate (HPNP) by complexes of RPAla and RPVal with La(III), Gd(III). ACTA ACUST UNITED AC 2007. [DOI: 10.1016/j.molcata.2006.05.057] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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13
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Bértolo E, Lodeiro C, Bastida R. Synthesis of four novel pendant armed macrocyclic ligands and their interaction with lanthanide(III) cations. RUSS J COORD CHEM+ 2006. [DOI: 10.1134/s1070328406120074] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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14
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High Yield Synthesis and Preliminary Spectroscopic Study of Mono-N-alkylated Cyclen Derivatives of Salicylic Acid. J INCL PHENOM MACRO 2006. [DOI: 10.1007/s10847-006-9101-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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15
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Gunnlaugsson T, Harte AJ. Synthesis and characterisation of bis-cyclen based dinuclear lanthanide complexes. Org Biomol Chem 2006; 4:1572-9. [PMID: 16604226 DOI: 10.1039/b514106k] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The design and synthesis of several bis-macrocyclic cyclen (1,4,7,10-tetraazacyclododecane) ligands and their corresponding lanthanum or europium complexes is described; these dinuclear lanthanide systems were made by connecting two macrocyclic cyclen moieties through a rigid, covalent, p-xylylenediamide bridge or a flexible aliphatic hexane bridge. These ligands were subsequently functionalised with six acetamide pendant arms (CONR1R2: R1 = R2 = H or CH3, or R1 = H, R2 = CH3). The corresponding lanthanide bis-complexes were then formed by reaction with La(III) and Eu(III) triflates, yielding overall cationic (+VI charged) complexes.
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Affiliation(s)
- Thorfinnur Gunnlaugsson
- School of Chemistry, Centre for Synthesis and Chemical Biology, Trinity College Dublin, Dublin 2, Ireland.
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Leonard JP, Gunnlaugsson T. Luminescent Eu(III) and Tb(III) Complexes: Developing Lanthanide Luminescent-Based Devices. J Fluoresc 2005; 15:585-95. [PMID: 16167216 DOI: 10.1007/s10895-005-2831-9] [Citation(s) in RCA: 138] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2004] [Accepted: 05/23/2005] [Indexed: 11/27/2022]
Abstract
This mini review gives some highlights of the work recently carried out in our research group in Dublin on the developments of lanthanide luminescent devices, where the future goal is to produce devices that can operate as sensors. A few examples demonstrate our design principles for targeting both anion and cations that are of biological or pharmaceutical relevance, where the recognition occurs in aqueous competitive media. We also discuss the possibility of developing mixed f-d metal complexes and conjugates that can be employed as novel supramolecular architectures.
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Affiliation(s)
- Joseph P Leonard
- Department of Chemistry, Centre for Synthesis and Chemical Biology, Trinity College Dublin, Dublin 2, Ireland
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Gunnlaugsson T, Leonard JP. Responsive lanthanide luminescent cyclen complexes: from switching/sensing to supramolecular architectures. Chem Commun (Camb) 2005:3114-31. [PMID: 15968347 DOI: 10.1039/b418196d] [Citation(s) in RCA: 271] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
This article highlights some of the recent developments in the use of responsive cyclen based lanthanide luminescent devices, focusing on Eu(III), Tb(III), Nd(III) and Yb(III) complexes, where the photophysical properties, such as the excited state lifetimes, quantum yield/intensity and emission polarisation are modulated by the local chemical environment, e.g. ions and molecules, or through self-assembly of either f-f or mixed f-d cyclen complexes.
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Cyclen based lanthanide ion ribonuclease mimics: the effect of pyridine cofactors upon phosphodiester HPNP hydrolysis. Tetrahedron Lett 2005. [DOI: 10.1016/j.tetlet.2005.03.150] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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20
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Gunnlaugsson T, Brougham DF, Fanning AM, Nieuwenhuyzen M, O'Brien JE, Viguier R. Effect on pKaof Metal-Bound Water Molecules in Lanthanide Ion-Induced Cyclen “Cavities”. Org Lett 2004; 6:4805-8. [PMID: 15606071 DOI: 10.1021/ol048628s] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
[reaction: see text] The macrocyclic cyclen conjugates 1-4 were synthesized with the aim of forming lanthanide ion-based macrocyclic conjugates possessing deep cavities, formed upon complexation to various lanthanide ions. These complexes all possess metal-bound water molecules, where the pKa of the water molecules depends on the nature of the cavity.
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Abstract
Synthetic metallonucleases are versatile metal ion catalysts that use multiple catalytic strategies for the cleavage of RNA. Recent work in the design of more active metallonucleases combines a single metal ion with functional groups that interact with RNA, including amino acid fragments or additional metal ions. Rate enhancements by multifunctional catalysts for cleavage of simple model substrates with good leaving groups are as high as 10(6) but somewhat lower (10(5)) for real RNA. However, cleavage of RNA substrates is complicated by different binding modes and steric interactions that can interfere with catalysis. Antisense oligonucleotides, peptides and small molecules that act as RNA recognition agents increase the strength of substrate binding, but not necessarily the catalytic rate constant. In general, catalytic strategies used by synthetic metallonucleases are probably not optimized. A better grasp of the mechanism of RNA cleavage by metal ions and more effort on positioning the metal ion complex with respect to the cleavage site may lead to improved catalysts.
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Affiliation(s)
- Janet R Morrow
- Department of Chemistry, University at Buffalo, State University of New York, Amherst, NY 14260-3000, USA.
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Synthesis, DNA intercalation and europium(III)-triggered DNA photocleavage by a bis-proflavine succinamide conjugate. Tetrahedron Lett 2004. [DOI: 10.1016/j.tetlet.2004.03.177] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Gunnlaugsson T, Leonard JP, Mulready S, Nieuwenhuyzen M. Three step vs one pot synthesis and X-ray crystallographic investigation of heptadentate triamide cyclen (1,4,7,10-tetraazacyclododecane) based ligands and some of their lanthanide ion complexes. Tetrahedron 2004. [DOI: 10.1016/j.tet.2003.10.086] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Gunnlaugsson T, Nieuwenhuyzen M, Nolan C. Synthesis, X-ray crystallographic, spectroscopic investigation and cleavage studies of HPNP by simple bispyridyl iron, copper, cobalt, nickel and zinc complexes as artificial nucleases. Polyhedron 2003. [DOI: 10.1016/s0277-5387(03)00471-6] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Synthesis and characterisation of novel 3′-O- and 5′-O- modified azobenzene-thymidine phosphoramidites and their oligonucleotide conjugates as colorimeter DNA probes and FRET quenchers. Tetrahedron Lett 2003. [DOI: 10.1016/j.tetlet.2003.09.115] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Gunnlaugsson T, Leonard JP, Sénéchal K, Harte AJ. pH Responsive Eu(III)−Phenanthroline Supramolecular Conjugate: Novel “Off−On−Off” Luminescent Signaling in the Physiological pH Range. J Am Chem Soc 2003; 125:12062-3. [PMID: 14518970 DOI: 10.1021/ja035425a] [Citation(s) in RCA: 206] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The formation of luminescent supramolecular ternary complexes in water: delayed luminescence sensing of aromatic carboxylates using coordinated unsaturated cationic heptadenatate lanthanide ion complexes.
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