1
|
Neutral W(V) Complexes Featuring the W2O2(µ-O)2 Core and Amino Acids or EDTA Derivatives as Ligands: Synthesis and Structural Characterization. INORGANICS 2023. [DOI: 10.3390/inorganics11030114] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/12/2023] Open
Abstract
Multinuclear complexes of heavy metals, such as tungsten, have demonstrated considerable potential as candidates for advanced radiocontrast agents. Of particular interest is the development of stable non-ionic compounds with high metal content and reasonably low osmolality in solution. Accordingly, we have synthesized a series of neutral W(V) complexes that contain the W2O2(µ-O)2 core and amino acids or disubstituted EDTA derivatives as ligands. The compounds were prepared from the oxalatotungstate(V) complex via a convenient procedure utilizing microwave heating. Their detailed characterization was accomplished by electrospray ionization high-resolution mass spectrometry (ESI-HRMS), 1H and 13C NMR spectroscopy, elemental analysis, and X-ray crystallography. Further experiments to evaluate the utility of the complexes as radiocontrast media were precluded by their poor aqueous solubility.
Collapse
|
2
|
Water-Soluble Chalcogenide W 6-Clusters: On the Way to Biomedical Applications. Int J Mol Sci 2022; 23:ijms23158734. [PMID: 35955875 PMCID: PMC9369320 DOI: 10.3390/ijms23158734] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Revised: 08/04/2022] [Accepted: 08/04/2022] [Indexed: 11/17/2022] Open
Abstract
Despite the great potential of octahedral tungsten cluster complexes in fields of biomedical applications such as X-ray computed tomography or angiography, there is only one example of a water-soluble W6Q8-cluster that has been reported in the literature. Herein we present the synthesis and a detailed characterization including X-ray structural analysis, NMR, IR, UV-Vis spectroscopies, HR-MS spectrometry, and the electrochemical behavior of two new cluster complexes of the general formula W6Q8L6 with phosphine ligands containing a hydrophilic carboxylic group, which makes the complexes soluble in an aqueous medium. The hydrolytic stability of the clusters' aqueous solutions allows us to investigate for the first time the influence of W6-clusters on cell viability. The results obtained clearly demonstrate their very low cytotoxicity, comparable to the least-toxic clusters presented in the literature.
Collapse
|
3
|
Varbanov HP, Glasnov T, Belaj F, Herbert S, Brumby T, Mösch-Zanetti NC. New strategies towards advanced CT contrast agents. Development of neutral and monoanionic sulfur-bridged W(V) dimeric complexes. Dalton Trans 2022; 51:11086-11097. [PMID: 35796232 DOI: 10.1039/d2dt01470j] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Multinuclear tungsten complexes are intriguing candidates for new contrast media that can provide substantial improvements in CT imaging diagnostics. Herein, we present a ligand strategy, based on amino acids, and mono- and disubstituted EDTA derivatives, that enables the development of stable complexes with high tungsten content and reasonably low osmolality. Accordingly, a series of neutral and monoanionic di-μ-sulfido W(V) dimers have been synthesized via a convenient procedure utilizing microwave heating in combination with ion-pair HPLC reaction monitoring. The compounds were characterized in detail by various techniques, including ESI-HRMS, NMR spectroscopy, HPLC, elemental analysis, and X-ray crystallography. The aqueous stability of the complexes under physiologically relevant conditions, and during heat sterilization was also examined as an initial assessment of their potential applicability as radiocontrast agents. Monoanionic complexes featuring monosubstituted EDTA derivatives have demonstrated high stability, while producing a lower number of ions in solution (resulting in lower osmolality) in comparison to their bis-anionic EDTA counterparts. Nevertheless, they exhibited insufficient water solubility for application as intravascular contrast agents. However, our study showed that aqueous solubility of this type of complexes can be tuned by small modifications in the ligand structure.
Collapse
Affiliation(s)
- Hristo P Varbanov
- Institute of Chemistry - Inorganic Chemistry, University of Graz, Schubertstraße 1/III, 8010 Graz, Austria.
| | - Toma Glasnov
- Institute of Chemistry - Medicinal Chemistry, University of Graz, Schubertstraße 1/IV, 8010 Graz, Austria
| | - Ferdinand Belaj
- Institute of Chemistry - Inorganic Chemistry, University of Graz, Schubertstraße 1/III, 8010 Graz, Austria.
| | - Simon Herbert
- Research & Development, Pharmaceuticals Laboratory, Bayer AG, 13342 Berlin, Germany
| | - Thomas Brumby
- Research & Development, Pharmaceuticals Laboratory, Bayer AG, 13342 Berlin, Germany
| | - Nadia C Mösch-Zanetti
- Institute of Chemistry - Inorganic Chemistry, University of Graz, Schubertstraße 1/III, 8010 Graz, Austria.
| |
Collapse
|
4
|
Aslan N, Ceylan B, Koç MM, Findik F. Metallic nanoparticles as X-Ray computed tomography (CT) contrast agents: A review. J Mol Struct 2020. [DOI: 10.1016/j.molstruc.2020.128599] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
|
5
|
Hsu JC, Nieves LM, Betzer O, Sadan T, Noël PB, Popovtzer R, Cormode DP. Nanoparticle contrast agents for X-ray imaging applications. WILEY INTERDISCIPLINARY REVIEWS-NANOMEDICINE AND NANOBIOTECHNOLOGY 2020; 12:e1642. [PMID: 32441050 DOI: 10.1002/wnan.1642] [Citation(s) in RCA: 49] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/03/2020] [Revised: 04/13/2020] [Accepted: 04/14/2020] [Indexed: 12/12/2022]
Abstract
X-ray imaging is the most widely used diagnostic imaging method in modern medicine and several advanced forms of this technology have recently emerged. Iodinated molecules and barium sulfate suspensions are clinically approved X-ray contrast agents and are widely used. However, these existing contrast agents provide limited information, are suboptimal for new X-ray imaging techniques and are developing safety concerns. Thus, over the past 15 years, there has been a rapid growth in the development of nanoparticles as X-ray contrast agents. Nanoparticles have several desirable features such as high contrast payloads, the potential for long circulation times, and tunable physicochemical properties. Nanoparticles have also been used in a range of biomedical applications such as disease treatment, targeted imaging, and cell tracking. In this review, we discuss the principles behind X-ray contrast generation and introduce new types of X-ray imaging modalities, as well as potential elements and chemical compositions that are suitable for novel contrast agent development. We focus on the progress in nanoparticle X-ray contrast agents developed to be renally clearable, long circulating, theranostic, targeted, or for cell tracking. We feature agents that are used in conjunction with the newly developed multi-energy computed tomography and mammographic imaging technologies. Finally, we offer perspectives on current limitations and emerging research topics as well as expectations for the future development of the field. This article is categorized under: Diagnostic Tools > in vivo Nanodiagnostics and Imaging Nanotechnology Approaches to Biology > Nanoscale Systems in Biology.
Collapse
Affiliation(s)
- Jessica C Hsu
- Department of Radiology, Perelman School of Medicine of the University of Pennsylvania, Philadelphia, Pennsylvania, USA.,Department of Bioengineering, School of Engineering and Applied Science of the University of Pennsylvania, Pennsylvania, USA
| | - Lenitza M Nieves
- Department of Radiology, Perelman School of Medicine of the University of Pennsylvania, Philadelphia, Pennsylvania, USA.,Department of Biochemistry and Molecular Biophysics, Perelman School of Medicine of the University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Oshra Betzer
- Faculty of Engineering and the Institute of Nanotechnology and Advanced Materials, Bar-Ilan University, Ramat Gan, Israel
| | - Tamar Sadan
- Faculty of Engineering and the Institute of Nanotechnology and Advanced Materials, Bar-Ilan University, Ramat Gan, Israel
| | - Peter B Noël
- Department of Radiology, Perelman School of Medicine of the University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Rachela Popovtzer
- Faculty of Engineering and the Institute of Nanotechnology and Advanced Materials, Bar-Ilan University, Ramat Gan, Israel
| | - David P Cormode
- Department of Radiology, Perelman School of Medicine of the University of Pennsylvania, Philadelphia, Pennsylvania, USA.,Department of Bioengineering, School of Engineering and Applied Science of the University of Pennsylvania, Pennsylvania, USA.,Department of Biochemistry and Molecular Biophysics, Perelman School of Medicine of the University of Pennsylvania, Philadelphia, Pennsylvania, USA
| |
Collapse
|
6
|
Koç MM, Aslan N, Kao AP, Barber AH. Evaluation of X-ray tomography contrast agents: A review of production, protocols, and biological applications. Microsc Res Tech 2019; 82:812-848. [PMID: 30786098 DOI: 10.1002/jemt.23225] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2018] [Revised: 01/02/2019] [Accepted: 01/12/2019] [Indexed: 12/25/2022]
Abstract
X-ray computed tomography is a strong tool that finds many applications both in medical applications and in the investigation of biological and nonbiological samples. In the clinics, X-ray tomography is widely used for diagnostic purposes whose three-dimensional imaging in high resolution helps physicians to obtain detailed image of investigated regions. Researchers in biological sciences and engineering use X-ray tomography because it is a nondestructive method to assess the structure of their samples. In both medical and biological applications, visualization of soft tissues and structures requires special treatment, in which special contrast agents are used. In this detailed report, molecule-based and nanoparticle-based contrast agents used in biological applications to enhance the image quality were compiled and reported. Special contrast agent applications and protocols to enhance the contrast for the biological applications and works to develop nanoparticle contrast agents to enhance the contrast for targeted drug delivery and general imaging applications were also assessed and listed.
Collapse
Affiliation(s)
- Mümin Mehmet Koç
- School of Engineering, University of Portsmouth, Portsmouth, United Kingdom.,Department of Physics, Kirklareli University, Kirklareli, Turkey
| | - Naim Aslan
- Department of Metallurgical and Materials Engineering, Munzur University, Tunceli, Turkey
| | - Alexander P Kao
- School of Engineering, University of Portsmouth, Portsmouth, United Kingdom
| | - Asa H Barber
- School of Engineering, London South Bank University, London, United Kingdom
| |
Collapse
|
7
|
Cormode DP, Naha PC, Fayad ZA. Nanoparticle contrast agents for computed tomography: a focus on micelles. CONTRAST MEDIA & MOLECULAR IMAGING 2014; 9:37-52. [PMID: 24470293 DOI: 10.1002/cmmi.1551] [Citation(s) in RCA: 197] [Impact Index Per Article: 19.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2013] [Revised: 05/15/2013] [Accepted: 05/28/2013] [Indexed: 12/23/2022]
Abstract
Computed tomography (CT) is an X-ray-based whole-body imaging technique that is widely used in medicine. Clinically approved contrast agents for CT are iodinated small molecules or barium suspensions. Over the past seven years there has been a great increase in the development of nanoparticles as CT contrast agents. Nanoparticles have several advantages over small molecule CT contrast agents, such as long blood-pool residence times and the potential for cell tracking and targeted imaging applications. Furthermore, there is a need for novel CT contrast agents, owing to the growing population of renally impaired patients and patients hypersensitive to iodinated contrast. Micelles and lipoproteins, a micelle-related class of nanoparticle, have notably been adapted as CT contrast agents. In this review we discuss the principles of CT image formation and the generation of CT contrast. We discuss the progress in developing nontargeted, targeted and cell tracking nanoparticle CT contrast agents. We feature agents based on micelles and used in conjunction with spectral CT. The large contrast agent doses needed will necessitate careful toxicology studies prior to clinical translation. However, the field has seen tremendous advances in the past decade and we expect many more advances to come in the next decade.
Collapse
Affiliation(s)
- David P Cormode
- Departments of Radiology, University of Pennsylvania, 3400 Spruce St, 1 Silverstein, Philadelphia, PA, 19104, USA
| | | | | |
Collapse
|
8
|
Abstract
Heterometallic cubane-type clusters were synthesized from the reaction of group 6 and 8 metallaboranes using transition-metal carbonyl compounds. Structural and spectroscopic study revealed the existence of novel “capped-cubane” geometry. In addition, the crystal structure of these clusters distinctly confirms the presence of boride unit as one of the vertices. These clusters possess 60 cluster valence electrons (cve) and six metal–metal bonds. A plausible pathway for the formation of ruthenium-capped cubane has been described.
Collapse
|
9
|
Petrov PA, Virovets AV, Alberola A, Llusar R, Konchenko SN. Unexpected transformation of a diamagnetic Mo3(μ3-S)(μ-S)3 to a paramagnetic Mo3(μ3-S)2(μ-S)3 cluster core by reaction of [Mo3S4(dppe)3Br3]PF6 with tBuSNa. Dalton Trans 2010; 39:8875-7. [PMID: 20730138 DOI: 10.1039/c0dt00675k] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Affiliation(s)
- Pavel A Petrov
- Nikolaev Institute of Inorganic Chemistry, Siberian Branch of RAS, Ak. Lavrentieva Av., 3, Novosibirsk, 630090, Russian Federation
| | | | | | | | | |
Collapse
|
10
|
Bechlars B, Issac I, Feuerhake R, Clérac R, Fuhr O, Fenske D. Syntheses, Structures and Magnetic Properties of New Chalcogen‐Bridged Heterodimetallic Cluster Compounds with Heterocubane Structure. Eur J Inorg Chem 2008. [DOI: 10.1002/ejic.200701154] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Bettina Bechlars
- Institut für Anorganische Chemie, Universität Karlsruhe, Engesserstr. 15, 76133 Karlsruhe, Germany
| | - Ibrahim Issac
- Institut für Anorganische Chemie, Universität Karlsruhe, Engesserstr. 15, 76133 Karlsruhe, Germany
| | - Robert Feuerhake
- Institut für Nanotechnologie, Forschungszentrum Karlsruhe, Hermann‐von‐Helmholtz‐Platz 1, 76344 Eggenstein‐Leopoldshafen, Germany
| | - Rodolphe Clérac
- Université Bordeaux 1, CNRS, Centre de Recherche Paul Pascal (UPR‐CNRS 8641), 115, Avenue du Dr. A. Schweitzer, 33600 Pessac, France
| | - Olaf Fuhr
- Institut für Nanotechnologie, Forschungszentrum Karlsruhe, Hermann‐von‐Helmholtz‐Platz 1, 76344 Eggenstein‐Leopoldshafen, Germany
| | - Dieter Fenske
- Institut für Anorganische Chemie, Universität Karlsruhe, Engesserstr. 15, 76133 Karlsruhe, Germany
- Institut für Nanotechnologie, Forschungszentrum Karlsruhe, Hermann‐von‐Helmholtz‐Platz 1, 76344 Eggenstein‐Leopoldshafen, Germany
| |
Collapse
|
11
|
Algarra AG, Basallote MG, Fernandez-Trujillo MJ, Llusar R, Safont VS, Vicent C. The Structure of ([W3Q4X3(dmpe)3]+, Y-) Ion Pairs (Q = S, Se; X = H, OH, Br; Y = BF4, PF6, dmpe = Me2PCH2CH2PMe2) in Dichloromethane Solution and the Effect of Ion-Pairing on the Kinetics of Proton Transfer to the Hydride Cluster [W3S4H3(dmpe)3]+. Inorg Chem 2006; 45:5774-84. [PMID: 16841981 DOI: 10.1021/ic0520770] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The 1H,19F HOESY spectra of the title compounds in CD2Cl2 solution indicate that the cluster cations form ion pairs with the BF4- and PF6- anions with a well-defined interionic structure that appears to be basically determined essentially by the nature of the X- ligand. For the clusters with X = H and OH, the structure of the ion pairs is such that the counteranion (Y-) and the X- ligands are placed close to each other. However, when the size and electron density of X- increase (X = Br), Y- is forced to move to a different site, far away from X-. The relevance of ion-pairing on the chemistry of these compounds is clearly seen through a decrease in the rate of proton transfer from HCl to the hydride cluster [W3S4H3(dmpe)3]+ in the presence of an excess of BF4-. The kinetic data for this reaction can be rationalized by considering that the ([W3S4H3(dmpe)3]+, BF4-) ion pairs are unproductive in the proton-transfer process. Theoretical calculations indicate that the real behavior can be more complex. Although the cluster can still form adducts with HCl in the presence of BF4-, the structures of the most-stable BF4--containing HCl adducts show H...H distances too large to allow the subsequent release of H2. In addition, the effective concentration of HCl is also reduced because of the formation of adducts as ClH...BF4-. As a consequence of both effects, the proton transfer takes place more slowly than for the case of the dihydrogen-bonded HCl adduct resulting from the unpaired cluster.
Collapse
Affiliation(s)
- Andrés G Algarra
- Departamento de Ciencia de los Materiales e Ingeniería Metalúrgica y Química Inorganica, Facultad de Ciencias, Universidad de Cadiz, Apartado 40, Puerto Real, 11510 Cadiz, Spain
| | | | | | | | | | | |
Collapse
|
12
|
Sokolov M, Esparza P, Hernandez-Molina R, Platas JG, Mederos A, Gavin JA, Llusar R, Vicent C. Preparation and Properties of the Full Series of Cuboidal Clusters [MoxW4-xSe4(H2O)12]n+ (n = 4−6) and Their Derivatives. Inorg Chem 2005; 44:1132-41. [PMID: 15859295 DOI: 10.1021/ic049298a] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Hydrothermal reactions between incomplete cuboidal cluster aqua complexes [M3Q4(H2O)9]4+ and M(CO)6 (M = Mo, W; Q = S, Se) offer easy access to the corresponding cuboidal clusters M4Q4. The complete series of homometal and mixed Mo/W clusters [Mo(x)W4-xQ4(H2O)12]n+ (x = 0-4, n = 4-6) has been prepared. Upon oxidation of the mixed-metal clusters, it is the W atom which is lost, allowing selective preparation of new trinuclear clusters [Mo2WSe4(H2O)9]4+ and [MoW2Se4(H2O)9]4+. The aqua complexes were converted by ligand exchange reactions into dithiophosphato and thiocyanato complexes, and crystal structures of [W4S4((EtO)2PS2)6], [MoW3S4((EtO)2PS2)6], [Mo4Se4((EtO)2PS2)6], [W4Se4((i-PrO)2PS2)6], and (NH4)6[W4Se4(NCS)12]-4H20 were determined. Cyclic voltammetry was performed on [Mo(x)W4-xCO4(H2O)12]n+, showing reversible redox waves 6+/5+ and 5+/4+. The lower oxidation states are more difficult to access as the number of W atoms increases. The [Mo2WSe4(H2O)9]4+ and [MoW2Se4(H2O)9]4+ species were derivatized into [Mo2WSe4(acac)3(py)3]+ and [MoW2Se4(acac)3(py)3]+, which were also studied by CV. When appropriate, the products were also characterized by FAB-MS and NMR (31P, 1H) data.
Collapse
Affiliation(s)
- M Sokolov
- A V Nikolayev Institute of Inorganic Chemistry, Novosibirsk 630090, Russia.
| | | | | | | | | | | | | | | |
Collapse
|
13
|
Llusar R, Uriel S. Heterodimetallic Chalcogen‐Bridged Cubane‐Type Clusters of Molybdenum and Tungsten Containing First‐Row Transition Metals. Eur J Inorg Chem 2003. [DOI: 10.1002/ejic.200390164] [Citation(s) in RCA: 108] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Rosa Llusar
- Departament de Ciències Experimentals, Universitat Jaume I, Campus de Riu Sec, P. O. Box 224, 12080 Castelló, Spain, Fax: (internat.) + 34‐964/728066
| | - Santiago Uriel
- Departamento de Química Orgánica − Química Física, Centro Politécnico Superior, Universidad de Zaragoza, María de Luna 3, 50015 Zaragoza, Spain, Fax: (internat.) + 34‐976/761879
| |
Collapse
|
14
|
Abstract
The first fullerene-based X-ray contrast agent (CA) has been designed, synthesized, and characterized. The new CA is an externally functionalized derivative of C60 that is conceptually based on contemporary X-ray CA, all of which use iodine as the X-ray attenuating vehicle and are based on the 2,4,6-triiodinated-benzene-ring substructure. Using a modified Bingel-type reaction, a single addend containing 6 iodine atoms and 8 protected hydroxyl groups was appended to C60 followed by the addition of 4 more addends each containing 4 protected hydroxyl groups. Final deprotection afforded the highly water-soluble (>460 mg/mL), non-ionic, highly-iodinated (24% I) fullerene for application as an X-ray contrast agent.
Collapse
Affiliation(s)
- Tim Wharton
- Department of Chemistry and the Center for Nanoscale Science and Technology, MS-60 Rice University, Houston, TX 77251-1892, USA
| | | |
Collapse
|
15
|
Toward fullerene-based X-ray contrast agents: design and synthesis of non-ionic, highly-iodinated derivatives of C60. Tetrahedron Lett 2002. [DOI: 10.1016/s0040-4039(01)02119-0] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
|
16
|
Yu SB, Droege M, Downey S, Segal B, Newcomb W, Sanderson T, Crofts S, Suravajjala S, Bacon E, Earley W, Delecki D, Watson AD. Dimeric W3SO3 cluster complexes: synthesis, characterization, and potential applications as X-ray contrast agents. Inorg Chem 2001; 40:1576-81. [PMID: 11261967 DOI: 10.1021/ic0001053] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Our continued research on the use of heavy metal cluster complexes as a new class of X-ray contrast agents in medical diagnostic imaging is described. A series of 2:3 cluster-ligand complexes, [(W(IV)3SO3)2L3]4- (L = linear polyaminopolycarboxylate ligands), were isolated from the reaction of aqua ion [W(IV)3SO3(H2O)9]4- (prepared in large quantities through an improved literature process) with respective ligands in refluxing DMF. The salts of [(W(IV)3SO3)2L3]4- complex anions were fully characterized using routine techniques such as elemental analysis, MS, HPLC, UV-vis, IR, and NMR. The solid structures of two complex anions, [(W(IV)3SO3)2(PDTA)3]4- and [(W(IV)3SO3)2(HO-PDTA)3]4-, were determined by X-ray crystallography. They are the first examples wherein two W(IV)3SO3 clusters are complexed and linked by three ligands that contain two terminal iminodiacetate (bis-IDA) groups. Complexation of the unstable aqua ion [W(IV)3SO3(H2O)9]4- with ligands has imparted desired biological compatibility to the tungsten metal cluster. These complexes are stable and highly soluble in H2O. The potential utility of such tungsten cluster complexes as X-ray contrast agents was evaluated in both in vitro and in vivo animal studies. In addition, the syntheses of several new linear polyaminopolycarboxylate ligands used in this study are reported.
Collapse
Affiliation(s)
- S B Yu
- Torsten Almén Research Center, Nycomed Amersham Imaging, 466 Devon Park Drive, Wayne, Pennsylvania 19087, USA
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|