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Gansäuer A, Winkler I, Worgull D, Franke D, Lauterbach T, Okkel A, Nieger M. Modular Synthesis of Functional Titanocenes. Organometallics 2008. [DOI: 10.1021/om800700c] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Andreas Gansäuer
- Kekulé-Institut für Organische Chemie und Biochemie der Universität Bonn, Gerhard Domagk Strasse 1, 53121 Bonn, Germany, and Laboratory of Inorganic Chemistry, Department of Chemistry, University of Helsinki, P.O. Box 55, FIN-00014 University of Helsinki, Finland
| | - Iris Winkler
- Kekulé-Institut für Organische Chemie und Biochemie der Universität Bonn, Gerhard Domagk Strasse 1, 53121 Bonn, Germany, and Laboratory of Inorganic Chemistry, Department of Chemistry, University of Helsinki, P.O. Box 55, FIN-00014 University of Helsinki, Finland
| | - Dennis Worgull
- Kekulé-Institut für Organische Chemie und Biochemie der Universität Bonn, Gerhard Domagk Strasse 1, 53121 Bonn, Germany, and Laboratory of Inorganic Chemistry, Department of Chemistry, University of Helsinki, P.O. Box 55, FIN-00014 University of Helsinki, Finland
| | - Dieter Franke
- Kekulé-Institut für Organische Chemie und Biochemie der Universität Bonn, Gerhard Domagk Strasse 1, 53121 Bonn, Germany, and Laboratory of Inorganic Chemistry, Department of Chemistry, University of Helsinki, P.O. Box 55, FIN-00014 University of Helsinki, Finland
| | - Thorsten Lauterbach
- Kekulé-Institut für Organische Chemie und Biochemie der Universität Bonn, Gerhard Domagk Strasse 1, 53121 Bonn, Germany, and Laboratory of Inorganic Chemistry, Department of Chemistry, University of Helsinki, P.O. Box 55, FIN-00014 University of Helsinki, Finland
| | - Andreas Okkel
- Kekulé-Institut für Organische Chemie und Biochemie der Universität Bonn, Gerhard Domagk Strasse 1, 53121 Bonn, Germany, and Laboratory of Inorganic Chemistry, Department of Chemistry, University of Helsinki, P.O. Box 55, FIN-00014 University of Helsinki, Finland
| | - Martin Nieger
- Kekulé-Institut für Organische Chemie und Biochemie der Universität Bonn, Gerhard Domagk Strasse 1, 53121 Bonn, Germany, and Laboratory of Inorganic Chemistry, Department of Chemistry, University of Helsinki, P.O. Box 55, FIN-00014 University of Helsinki, Finland
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Pereira CCL, Diogo CV, Burgeiro A, Oliveira PJ, Marques MPM, Braga SS, Paz FAA, Pillinger M, Gonçalves IS. Complex Formation between Heptakis(2,6-di-O-methyl)-β-cyclodextrin and Cyclopentadienyl Molybdenum(II) Dicarbonyl Complexes: Structural Studies and Cytotoxicity Evaluations. Organometallics 2008. [DOI: 10.1021/om800413w] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Cláudia C. L. Pereira
- Department of Chemistry, CICECO, University of Aveiro, 3810-193 Aveiro, Portugal, Center for Neuroscience and Cell Biology, Department of Zoology, University of Coimbra, 3004-517 Coimbra, Portugal, and Department of Biochemistry, Faculty of Science and Technology, University of Coimbra, Apartado 3126, 3001-401 Coimbra, Portugal
| | - Cátia V. Diogo
- Department of Chemistry, CICECO, University of Aveiro, 3810-193 Aveiro, Portugal, Center for Neuroscience and Cell Biology, Department of Zoology, University of Coimbra, 3004-517 Coimbra, Portugal, and Department of Biochemistry, Faculty of Science and Technology, University of Coimbra, Apartado 3126, 3001-401 Coimbra, Portugal
| | - Ana Burgeiro
- Department of Chemistry, CICECO, University of Aveiro, 3810-193 Aveiro, Portugal, Center for Neuroscience and Cell Biology, Department of Zoology, University of Coimbra, 3004-517 Coimbra, Portugal, and Department of Biochemistry, Faculty of Science and Technology, University of Coimbra, Apartado 3126, 3001-401 Coimbra, Portugal
| | - Paulo J. Oliveira
- Department of Chemistry, CICECO, University of Aveiro, 3810-193 Aveiro, Portugal, Center for Neuroscience and Cell Biology, Department of Zoology, University of Coimbra, 3004-517 Coimbra, Portugal, and Department of Biochemistry, Faculty of Science and Technology, University of Coimbra, Apartado 3126, 3001-401 Coimbra, Portugal
| | - Maria Paula M. Marques
- Department of Chemistry, CICECO, University of Aveiro, 3810-193 Aveiro, Portugal, Center for Neuroscience and Cell Biology, Department of Zoology, University of Coimbra, 3004-517 Coimbra, Portugal, and Department of Biochemistry, Faculty of Science and Technology, University of Coimbra, Apartado 3126, 3001-401 Coimbra, Portugal
| | - Susana S. Braga
- Department of Chemistry, CICECO, University of Aveiro, 3810-193 Aveiro, Portugal, Center for Neuroscience and Cell Biology, Department of Zoology, University of Coimbra, 3004-517 Coimbra, Portugal, and Department of Biochemistry, Faculty of Science and Technology, University of Coimbra, Apartado 3126, 3001-401 Coimbra, Portugal
| | - Filipe A. Almeida Paz
- Department of Chemistry, CICECO, University of Aveiro, 3810-193 Aveiro, Portugal, Center for Neuroscience and Cell Biology, Department of Zoology, University of Coimbra, 3004-517 Coimbra, Portugal, and Department of Biochemistry, Faculty of Science and Technology, University of Coimbra, Apartado 3126, 3001-401 Coimbra, Portugal
| | - Martyn Pillinger
- Department of Chemistry, CICECO, University of Aveiro, 3810-193 Aveiro, Portugal, Center for Neuroscience and Cell Biology, Department of Zoology, University of Coimbra, 3004-517 Coimbra, Portugal, and Department of Biochemistry, Faculty of Science and Technology, University of Coimbra, Apartado 3126, 3001-401 Coimbra, Portugal
| | - Isabel S. Gonçalves
- Department of Chemistry, CICECO, University of Aveiro, 3810-193 Aveiro, Portugal, Center for Neuroscience and Cell Biology, Department of Zoology, University of Coimbra, 3004-517 Coimbra, Portugal, and Department of Biochemistry, Faculty of Science and Technology, University of Coimbra, Apartado 3126, 3001-401 Coimbra, Portugal
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Hogan M, Cotter J, Claffey J, Gleeson B, Wallis D, O'Shea D, Tacke M. Synthesis and Cytotoxicity Studies of New (Dimethylamino)-Functionalised and 7-Azaindole-Substituted ‘Titanocene’ Anticancer Agents (7-Azaindole=1H-Pyrrolo[2,3-b]pyridine). Helv Chim Acta 2008. [DOI: 10.1002/hlca.200890191] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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54
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Gómez-Ruiz S, Kaluđerović GN, Prashar S, Polo-Cerón D, Fajardo M, Žižak Ž, Sabo TJ, Juranić ZD. Cytotoxic studies of substituted titanocene and ansa-titanocene anticancer drugs. J Inorg Biochem 2008; 102:1558-70. [DOI: 10.1016/j.jinorgbio.2008.02.001] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2007] [Revised: 01/23/2008] [Accepted: 02/04/2008] [Indexed: 10/22/2022]
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55
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Gansäuer A, Winkler I, Worgull D, Lauterbach T, Franke D, Selig A, Wagner L, Prokop A. Carbonyl-substituted titanocenes: a novel class of cytostatic compounds with high antitumor and antileukemic activity. Chemistry 2008; 14:4160-3. [PMID: 18384037 DOI: 10.1002/chem.200800407] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Andreas Gansäuer
- Kekulé-Institut für Organische Chemie und Biochemie, Universität Bonn, Gerhard-Domagk-Str. 1, 53121 Bonn, Germany.
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56
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Serra D, McElwee-White L. Electrochemical oxidation of methanol using alcohol-soluble Ru/Pt and Ru/Pd catalysts. Inorganica Chim Acta 2008. [DOI: 10.1016/j.ica.2007.10.046] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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57
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Hernández R, Lamboy J, Gao LM, Matta J, Román FR, Meléndez E. Structure-activity studies of Ti(IV) complexes: aqueous stability and cytotoxic properties in colon cancer HT-29 cells. J Biol Inorg Chem 2008; 13:685-92. [PMID: 18288505 PMCID: PMC4461444 DOI: 10.1007/s00775-008-0353-z] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2007] [Accepted: 02/05/2008] [Indexed: 11/30/2022]
Abstract
As part of our research efforts in the area of titanium-based antitumor agents, we have investigated the cytotoxic activity of [Ti(4)(maltolato)(8)(mu-O)(4)], (Cp-R)(2)TiCl(2) and (Cp-R)CpTiCl(2) (R = CO(2)CH(3) and CO(2)CH(2)CH(3)), and three water-soluble titanocene-amino acid complexes-[Cp(2)Ti(aa)(2)]Cl(2) (aa = L: -cysteine, L: -methionine, and D: -penicillamine)-on the human colon adenocarcinoma cell line, HT-29. The capacity of [Ti(4)(maltolato)(8)(mu-O)(4)] to donate Ti(IV) to human apo-transferrin and its hydrolytic stability have been investigated and compared to the previously reported data on modified titanocenes with either hydrophilic ancillary ligands or the functionalized cyclopentadienyl ligands. Notably, the titanium-maltolato complex does not transfer Ti(VI) to human apo-transferrin at any time within the first seven days of its interaction, demonstrating the inert character of this species. Stability studies on these complexes have shown that titanocene complexes decompose at physiological pH while the [Ti(4)(maltolato)(8)(mu-O)(4)] complex is stable at this pH without any notable decomposition for a period of ten days. The antitumor activity of these complexes against colon cancer HT-29 cells was determined using an MTT cell viability assay at 72 and 96 h. The titanocene-amino acid and the (Cp-R)(2)TiCl(2)/(Cp-R)CpTiCl(2) (R = CO(2)CH(3)) complexes were not biologically active when human transferrin was absent; they also were inactive when human transferrin was present at dose-equivalent concentrations. (Cp-R)(2)TiCl(2) and (Cp-R)CpTiCl(2) (R = CO(2)CH(2)CH(3)) showed cytotoxic activity in HT-29 cells comparable to that which is displayed by titanocene dichloride. The titanium-maltolato complex had higher levels of cytotoxic activity than any other titanocene complex investigated. Transferrin may be important in protecting the titanium center from hydrolysis, but this may be achieved by selecting ligands that could result in hydrolytically stable, yet active, complexes.
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Affiliation(s)
- Ramón Hernández
- Department of Chemistry, University of Puerto Rico, Mayaguez, PR 00681, USA
| | - José Lamboy
- Department of Chemistry, University of Puerto Rico, Mayaguez, PR 00681, USA
| | - Li Ming Gao
- Department of Chemistry, University of Puerto Rico, Mayaguez, PR 00681, USA
| | - Jaime Matta
- Department of Pharmacology, Toxicology and Physiology, Ponce School of Medicine, Ponce, PR 00732-7004, USA
| | - Félix R. Román
- Department of Chemistry, University of Puerto Rico, Mayaguez, PR 00681, USA
| | - Enrique Meléndez
- Department of Chemistry, University of Puerto Rico, Mayaguez, PR 00681, USA
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58
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Claffey J, Hogan M, Müller-Bunz H, Pampillón C, Tacke M. Synthesis and cytotoxicity studies of methoxy benzyl substituted titanocenes. J Organomet Chem 2008. [DOI: 10.1016/j.jorganchem.2007.11.037] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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59
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Strohfeldt K, Tacke M. Bioorganometallic fulvene-derived titanocene anti-cancer drugs. Chem Soc Rev 2008; 37:1174-87. [DOI: 10.1039/b707310k] [Citation(s) in RCA: 280] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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60
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Pampillón C, Claffey J, Hogan M, Tacke M. Morpholino-Functionalized and Heteroaryl-Substituted Titanocene Anti-Cancer Drugs: Synthesis and Cytotoxicity Studies. Z Anorg Allg Chem 2007. [DOI: 10.1002/zaac.200700212] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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61
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Pampillón C, Claffey J, Hogan M, Tacke M. Novel achiral titanocene anti-cancer drugs synthesised from bis-N,N-dimethylamino fulvene and lithiated heterocyclic compounds. Biometals 2007; 21:197-204. [PMID: 17665139 DOI: 10.1007/s10534-007-9108-5] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2007] [Accepted: 06/27/2007] [Indexed: 11/26/2022]
Abstract
From the carbolithiation of 6-bis-N,N-dimethylamino fulvene (3a) and different ortho-lithiated heterocycles (furan, thiophene and N-methylpyrrole), the corresponding lithium cyclopentadienide intermediate (4a-c) was formed. These three lithiated intermediates underwent a transmetallation reaction with TiCl(4) resulting in bis-N,N-dimethylamino-functionalised titanocenes 5a-c. When these titanocenes were tested against LLC-PK cells, the IC(50)-values obtained were of 240, and 270 microM for titanocenes 5b and 5c, respectively. The most cytotoxic titanocene in this paper, 5a with an IC(50)-value of 36 microM was found to be approximately six times less cytotoxic than its mono-N,N-dimethylamino substituted analogue Titanocene C (IC(50) = 5.5 microM) and almost ten times less cytotoxic than cisplatin, which showed an IC(50)-value of 3.3 microM, when tested on the LLC-PK cell line.
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Affiliation(s)
- Clara Pampillón
- Conway Institute of Biomolecular and Biomedical Research, The UCD School of Chemistry and Chemical Biology, Centre for Synthesis and Chemical Biology (CSCB), University College Dublin, Belfield, Dublin 4, Ireland
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Gómez-Ruiz S, Kaluđerović GN, Polo-Cerón D, Prashar S, Fajardo M, Žižak Ž, Juranić ZD, Sabo TJ. Study of the cytotoxic activity of alkenyl-substituted ansa-titanocene complexes. INORG CHEM COMMUN 2007. [DOI: 10.1016/j.inoche.2007.03.016] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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63
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Potter GD, Baird MC, Cole SP. A new series of titanocene dichloride derivatives bearing cyclic alkylammonium groups: Assessment of their cytotoxic properties. J Organomet Chem 2007. [DOI: 10.1016/j.jorganchem.2007.04.024] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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64
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Gao LM, Hernández R, Matta J, Meléndez E. Synthesis, Ti(IV) intake by apotransferrin and cytotoxic properties of functionalized titanocene dichlorides. J Biol Inorg Chem 2007; 12:959-67. [PMID: 17566797 DOI: 10.1007/s00775-007-0268-0] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2007] [Accepted: 05/24/2007] [Indexed: 11/30/2022]
Abstract
Functionalization of cyclopentadienyl (Cp) ligands and incorporation of these into a Ti(IV) center require careful design and selection of the appropriate synthetic routes to obtain the desired product in reasonably good yields. As part of our research efforts in the area of titanocene antitumor agents, we have revisited the synthesis of Cp rings with electron-withdrawing groups and their corresponding titanocene dichlorides, (Cp-R)(2)TiCl(2) and (Cp-R)CpTiCl(2), where R is CO(2)CH(3) and CO(2)CH(2)CH(3). These complexes were characterized by elemental analysis and (1)H and (13)C NMR and IR spectroscopies. This report presents the first detailed synthetic route for (Cp-CO(2)CH(2)CH(3))CpTiCl(2) and provides an alternate route for synthesis of (Cp-R)(2)TiCl(2) complexes. The ability of these complexes to deliver Ti(IV) to apotransferrin was investigated to elucidate how the functionalized Cp ligands affect the titanium intake by apotransferrin. The subject complexes transfer Ti(IV) to human apotransferrin, loading both N- and C-lobes. The antitumor activity of these complexes against HT-29 cancer colon cells was determined using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Carboethoxy Cp functionalization results in complexes with a toxicity comparable to that of titanocene dichloride. The carbomethoxy-functionalized complexes proved to be nonactive at the time intervals studied here, regardless of their ability to donate the titanium atom to human apotransferrin.
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Affiliation(s)
- Li Ming Gao
- Department of Chemistry, University of Puerto Rico, Mayaguez 00681, Puerto Rico
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65
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Honzíček J, Almeida Paz FA, Romão CC. Synthesis, Characterization and Stability of Spirodiene Complexes of Molybdenum(II): New Route toansa-Molybdenocene and Ring-Functionalized Molybdenocene Compounds. Eur J Inorg Chem 2007. [DOI: 10.1002/ejic.200700121] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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66
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Hickey T, Claffey J, Fitzpatrick E, Hogan M, Pampillón C, Tacke M. Dimethylamino-functionalised and N-heteroaryl-substituted titanocene anticancer drugs: synthesis and cytotoxicity studies. Invest New Drugs 2007; 25:425-33. [PMID: 17516024 DOI: 10.1007/s10637-007-9061-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2007] [Accepted: 04/25/2007] [Indexed: 11/26/2022]
Abstract
From the carbolithiation of 6-N,N-dimethylamino fulvene (3a) and different lithiated N-heterocyclic compounds (N,N-dimethylaminomethylpyrrole, 1-methylimidazole and 2,4-[bis(N',N'-dimethylaminomethyl)]-N-methyl pyrrole), the corresponding lithium cyclopentadienide intermediate (4a-c) was formed. These three lithiated intermediates underwent a transmetallation reaction with TiCl4 resulting in dimethylamino-functionalised titanocenes 5a-c. When these titanocenes were tested against LLC-PK cells, the IC50 values obtained were of 13, and 63 microM for titanocenes 5b and 5c, respectively. The most cytotoxic titanocene in this paper (5a) with an IC50 value of 6.8 microM is found to be almost as cytotoxic as cis-platin, which showed an IC50 value of 3.3 microM, when tested on the epithelial pig kidney LLC-PK cell line, and titanocene 5c is approximately 400 times better than titanocene dichloride itself.
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Affiliation(s)
- Thomas Hickey
- Conway Institute of Biomolecular and Biomedical Research, The UCD School of Chemistry and Chemical Biology, Centre for Synthesis and Chemical Biology (CSCB), University College Dublin, Belfield, Dublin 4, Ireland
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67
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Pampillón C, Claffey J, Hogan M, Strohfeldt K, Tacke M. Synthesis and cytotoxicity studies of new dimethylamino-functionalised and indolyl-substituted titanocene anti-cancer drugs. TRANSIT METAL CHEM 2007. [DOI: 10.1007/s11243-006-0183-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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68
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Hogan M, Claffey J, Pampillón C, Watson RWG, Tacke M. Synthesis and Cytotoxicity Studies of New Dimethylamino-Functionalized and Azole-Substituted Titanocene Anticancer Drugs. Organometallics 2007. [DOI: 10.1021/om070088q] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Megan Hogan
- Conway Institute of Biomolecular and Biomedical Research, University College Dublin, Belfield, Dublin 4, Ireland
| | - James Claffey
- Conway Institute of Biomolecular and Biomedical Research, University College Dublin, Belfield, Dublin 4, Ireland
| | - Clara Pampillón
- Conway Institute of Biomolecular and Biomedical Research, University College Dublin, Belfield, Dublin 4, Ireland
| | - R. William G. Watson
- Conway Institute of Biomolecular and Biomedical Research, University College Dublin, Belfield, Dublin 4, Ireland
| | - Matthias Tacke
- Conway Institute of Biomolecular and Biomedical Research, University College Dublin, Belfield, Dublin 4, Ireland
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Oberschmidt O, Hanauske AR, Pampillón C, Sweeney NJ, Strohfeldt K, Tacke M. Antiproliferative activity of Titanocene Y against tumor colony-forming units. Anticancer Drugs 2007; 18:317-21. [PMID: 17264765 DOI: 10.1097/cad.0b013e3280115f86] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Bis-[(p-methoxybenzyl)cyclopentadienyl] titanium dichloride, better known as Titanocene Y, is a newly synthesized titanium-based anticancer drug. We studied the antitumor activity of Titanocene Y with concentrations of 2.1, 21 and 210 micromol/l against a range of freshly explanted human tumors, using an in-vitro soft agar cloning system. The sensitivity against Titanocene Y was highly remarkable in the case of renal cell, ovarian, nonsmall cell lung and colon cancer. In particular the surprisingly good response of nonsmall cell lung cancer and colon cancer against Titanocene Y at its lowest concentration of 2.1 micromol/l was well comparable or better with respect to cisplatin, given at a concentration of 1.0 micromol/l. Further clinical development of Titanocene Y appears to be warranted because of the broad cytotoxic activity shown and the specific activity of Titanocene Y against renal cell cancer.
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71
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Allen OR, Gott AL, Hartley JA, Hartley JM, Knox RJ, McGowan PC. Functionalised cyclopentadienyl titanium compounds as potential anticancer drugs. Dalton Trans 2007:5082-90. [DOI: 10.1039/b708283p] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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72
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Sweeney NJ, Claffey J, Müller-Bunz H, Pampillón C, Strohfeldt K, Tacke M. The synthesis and cytotoxic evaluation of a series of benzodioxole substituted titanocenes. Appl Organomet Chem 2007. [DOI: 10.1002/aoc.1177] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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73
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Abeysinghe PM, Harding MM. Antitumour bis(cyclopentadienyl) metal complexes: titanocene and molybdocene dichloride and derivatives. Dalton Trans 2007:3474-82. [PMID: 17680034 DOI: 10.1039/b707440a] [Citation(s) in RCA: 169] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
This Perspective will focus on recent developments in the field of antitumour metallocenes structurally related to titanocene dichloride. Despite extensive testing of titanocene dichloride which culminated in phase I and II clinical trials, further trials have been abandoned. While DNA has been implicated as the major target related to anticancer activity, identification of the active species and mechanism of action has been poorly understood and hence the design of second generation titanocene derivatives has not been possible. Recent mechanistic studies have provided a plausible mechanism for delivery of Ti to cancer cells via transferrin mediated endocytosis. This mechanism requires the presence of labile Cp-Ti bonds that hydrolyse on a time scale to deliver Ti to transferrin. A large range of titanocene derivatives in which the cyclopentadienyl rings have been substituted by both electron withdrawing and donating groups, including aromatic, alkyl and cyclic amines, have been prepared and tested for activity in the last 5 years. These results have shown that subtle structural effects can have a significant effect on biological activity and that biological activity is highly cell line dependent. However, the biological chemistry and cellular studies required to determine the mechanism of action of these new titanocenes have not been reported. In contrast, the bioorganometallic chemistry and cellular studies of molybdocene dichloride have implicated interaction with cellular thiols as the key reaction related to biological activity. Tailoring of the pseudohalide ligands by tuning the strength of the Mo-S bonds provides the opportunity to enhance cell uptake. Further research is required to establish the origin of antitumour activity.
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Fichtner I, Pampillón C, Sweeney NJ, Strohfeldt K, Tacke M. Anti-tumor activity of Titanocene Y in xenografted Caki-1 tumors in mice. Anticancer Drugs 2006; 17:333-6. [PMID: 16520662 DOI: 10.1097/00001813-200603000-00012] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
The benzyl-substituted unbridged titanocene bis-[(p-methoxybenzyl)cyclopentadienyl] titanium(IV) dichloride (Titanocene Y) was tested in vitro against human renal cancer cells (Caki-1), in which it showed an IC50 value of 36 x 10 mol/l. Titanocene Y was then given in vivo in doses of 10, 20, 30, 40 and 50 mg/kg on 5 consecutive days to Caki-1-bearing mice, and it showed concentration-dependent and statistically significant tumor growth reduction with respect to a solvent-treated control cohort. The maximum tolerable dose of Titanocene Y was determined to be 40 mg/kg and it showed significantly better tumor volume growth reduction than cisplatin given at a dose of 2 mg/kg. This superior activity of Titanocene Y with respect to cisplatin will hopefully lead to clinical tests against metastatic renal cell cancer in the near future.
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Affiliation(s)
- Iduna Fichtner
- aMax Delbrück Center for Molecular Medicine, Berlin, Germany
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75
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Cellular toxicities of new titanocene dichloride derivatives containing pendant cyclic alkylammonium groups. INORG CHEM COMMUN 2006. [DOI: 10.1016/j.inoche.2006.07.019] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Sponer JE, Leszczynski J, Sponer J. Mechanism of Action of Anticancer Titanocene Derivatives: An Insight from Quantum Chemical Calculations. J Phys Chem B 2006; 110:19632-6. [PMID: 17004831 DOI: 10.1021/jp063477r] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Titanocene derivatives exhibit high potential in the treatment of cisplatin-resistant tumor types. Density functional theory calculations were performed on the hydrated form of five drug candidates differing in the pendant arms attached to the aromatic rings. A qualitative correlation has been found between the experimentally measured anticancer activity of alkylammonium-functionalized titanocene derivatives and the computed free energy change of the proton-induced dissociation reaction of these compounds. The results indicate that differences in the cytotoxic activities could be related to the solvation properties of the protolysis products, whereas no correlation was found with gas-phase properties of these molecules. Contrary to the free energy change of the protolysis reaction, other molecular properties, such as the geometrical parameters or the binding energies of the cyclopentadienyl rings in solution, do not correlate with the in vitro cytotoxic activity of these drug candidates.
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Affiliation(s)
- Judit E Sponer
- Institute of Biophysics, Academy of Sciences of the Czech Republic, Kralovopolska 135, 61265 Brno, Czech Republic.
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Diheteroarylmethyl substituted titanocenes: A novel class of possible anti-cancer drugs. Inorganica Chim Acta 2006. [DOI: 10.1016/j.ica.2006.05.021] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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78
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Pampillón C, Mendoza O, Sweeney NJ, Strohfeldt K, Tacke M. Diarylmethyl substituted titanocenes: Promising anti-cancer drugs. Polyhedron 2006. [DOI: 10.1016/j.poly.2006.01.007] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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79
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O'Connor K, Gill C, Tacke M, Rehmann FJK, Strohfeldt K, Sweeney N, Fitzpatrick JM, Watson RWG. Novel titanocene anti-cancer drugs and their effect on apoptosis and the apoptotic pathway in prostate cancer cells. Apoptosis 2006; 11:1205-14. [PMID: 16699961 DOI: 10.1007/s10495-006-6796-1] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
Advanced prostate cancer is not curable by current treatment strategies indicating a significant need for new chemotherapeutic options. Highly substituted ansa-titanocene compounds have shown promising cytotoxic activity in a range of cancers. The objectives of this study are to examine the effects of these titanocene compounds on prostate cancer cells. Prostate cell lines were treated with three novel titanocene compounds and compared to titanocene dichloride and cisplatin. Percent apoptosis, viability and cell cycle were assessed using propidium iodide DNA incorporation with flow cytometry. Cytochrome C was assessed by western blotting of mitochondrial and cytoplasmic fractions. Apoptosis Inducing Factor was assessed by confocal microscopy. These novel compounds induced more apoptosis compared to cisplatin in a dose dependent manner. Compound Y had the most significant effect on cell cycle and apoptosis. Despite the release of cytochrome C from the mitochondrial fraction there was no inhibition of apoptosis with the pan caspase inhibitor, ZVAD-FMK. AIF was shown to translocate from the cytosol to the nucleus mediating a caspase independent cell death. Bcl-2 over expressing PC-3 cells, which were resistant to cisplatin induced apoptosis, underwent apoptosis following treatment with all the titanocene compounds. This study demonstrates possible mechanisms by which these novel titanocene compounds can mediate their apoptotic effect in vitro. The fact that they can induce more apoptosis than cisplatin in advanced cancer cell lines would confer an advantage over cisplatin. They represent exciting new agents with future potential for the treatment of advanced prostate cancer.
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Affiliation(s)
- K O'Connor
- UCD School of Medicine and Medical Sciences, Mater Misericordiae University Hospital, University College Dublin, Belfield, Dublin 4, Ireland
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80
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Sweeney N, Gallagher WM, Müller-Bunz H, Pampillón C, Strohfeldt K, Tacke M. Heteroaryl substituted titanocenes as potential anti-cancer drugs. J Inorg Biochem 2006; 100:1479-86. [PMID: 16764931 DOI: 10.1016/j.jinorgbio.2006.04.006] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2005] [Revised: 04/04/2006] [Accepted: 04/06/2006] [Indexed: 10/24/2022]
Abstract
From the reaction of Super Hydride (LiBEt(3)H) with 6-(furyl)fulvene (1a), 6-(thiophenyl)fulvene (1b) or 6-(N-methyl-pyrrole)fulvene (1c) the corresponding lithium cyclopentadienide intermediates (2a-c) were obtained. These intermediates were reacted with titanium tetrachloride and bis-[(furyl-2-cyclopentadienylmethane)] titanium(IV) dichloride (3a) and bis-[(thiophenyl-2-cyclopentadienylmethane)] titanium(IV) dichloride (3b) and bis-[(N-methylpyrrole-2-cyclopentadienylmethane)] titanium(IV) dichloride (3c) were obtained and subsequently characterised by X-ray crystallography. When titanocenes 3a-c were tested against pig kidney (LLC-PK) cells inhibitory concentrations (IC(50)) of 1.6x10(-4)M, 1.5x10(-4)M and 9.1x10(-4)M, respectively, were observed. These values represent improved cytotoxicity against LLC-PK, when compared to their corresponding ansa substituted analogues and also in comparison to unsubstituted titanocene dichloride.
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Affiliation(s)
- Nigel Sweeney
- Conway Institute of Biomolecular and Biomedical Research, The UCD School of Chemistry and Chemical Biology, Centre for Synthesis and Chemical Biology (CSCB), Belfield, Dublin 4, Ireland
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82
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Oberschmidt O, Hanauske AR, Rehmann FJK, Strohfeldt K, Sweeney N, Tacke M. Activity of [1,2-di(cyclopentadienyl)-1,2-di(p-N,N-dimethylaminophenyl)-ethanediyl] titanium dichloride against tumor colony-forming units. Anticancer Drugs 2005; 16:1071-3. [PMID: 16222148 DOI: 10.1097/00001813-200511000-00005] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
[1,2-di(cyclopentadienyl)-1,2-di(p-N,N-dimethylaminophenyl)-ethanediyl] titanium dichloride is a newly synthesized transition metal-based anti-cancer drug. We studied the anti-tumor activity of this drug (final concentrations: 25, 250 and 2,500 micromol/l) against freshly explanted human tumors, using an in vitro soft agar cloning system. A total of eight tumor samples were evaluated using 1-h exposures. Additionally, the breast carcinoma cell line MCF-7 was examined with regard to sensitivity. The tested compound was markedly active against one renal cancer sample, whereas other renal tumors were resistant. Concentration-dependent anti-tumor activity was demonstrated for all samples except for melanoma. At concentrations of 250 micromol/l or less, the compound was less active than cisplatin or equally active at 0.2 microg/ml, whereas at 2,500 micromol/l it showed a significant cytotoxic activity against a wide spectrum of tumor types. The highest activity was observed against renal carcinomas (three of three tumor specimens inhibited at 2,500 micromol/l). Sensitivity was also highly remarkable in the breast cancer cell line MCF-7 inhibited in a range of 25-2,500 micromol/l, whereas melanoma cells seemed to be profoundly resistant. Further clinical development of this drug appears warranted because of the broad cytotoxic activity shown.
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Kelter G, Sweeney NJ, Strohfeldt K, Fiebig HH, Tacke M. In-vitro anti-tumor activity studies of bridged and unbridged benzyl-substituted titanocenes. Anticancer Drugs 2005; 16:1091-8. [PMID: 16222151 DOI: 10.1097/00001813-200511000-00008] [Citation(s) in RCA: 92] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
The benzyl-substituted ansa-titanocenes [1,2-di(cyclopentadienyl)-1,2-di-(4-N,N-dimethylaminophenyl)ethanediyl] titanium dichloride (Titanocene X) and [1,2-di(cyclopentadienyl)-1,2-bis(m-dimethoxyphenyl)ethanediyl] titanium dichloride (Titanocene Z), and the benzyl-substituted unbridged titanocene bis-[(p-methoxybenzyl)cyclopentadienyl] titanium(IV) dichloride (Titanocene Y) were tested on the growth of a wide variety of tumor cells in vitro on a panel of 36 human tumor cell lines containing 14 different tumor types investigated in a cellular proliferation assay. Titanocene Y with a mean IC50 value of 65.8 x 10 mol/l over the full panel of 36 cancer cell lines reaches the activity of cisplatin with 14.7 x 10 mol/l within a factor of 4, whereas Titanocene X and Z show significantly less cytotoxic activity. Titanocene Y is most effective on pleura mesothelioma, and uterine and renal cell cancer, where the IC50 values are comparable or significantly better than for cisplatin. In particular, in the case of renal cell cancer and pleura mesothelioma there is an obvious lack of chemotherapeutic reagents, which might be filled by Titanocene Y, where a very promising cytotoxic effect in comparison with cisplatin could be shown.
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Affiliation(s)
- Gerhard Kelter
- Oncotest GmbH, Institute of Experimental Oncology, Freiburg, Germany
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Sweeney NJ, Mendoza O, Müller-Bunz H, Pampillón C, Rehmann FJK, Strohfeldt K, Tacke M. Novel benzyl substituted titanocene anti-cancer drugs. J Organomet Chem 2005. [DOI: 10.1016/j.jorganchem.2005.06.039] [Citation(s) in RCA: 108] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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85
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Synthesis, characterization and structure of the Bis(methyl-cyclopentadienyl)vanadium(IV) carboxylates. OPEN CHEM 2005. [DOI: 10.2478/bf02476246] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
AbstractThe 1,1’-dimethylvanadocene dichloride ((C5H4CH3)2VCl2) reacts in aqueous solution with various carboxylic acids giving two different types of complexes. The 1,1’-dimethylvanadocene complexes of monocarboxylic acids (C5H4CH3)2V(OOCR)2 (R=H,CCl3, CF3, C6H5) contain two monodentate carboxylic ligands, whereas oxalic and malonic acids act as chelate compounds of the formula (C5H4CH3)2V(OOC-A-COO) (A=−, CH2). The structure of the (C5H4CH3)2 V(OOCCF3)2 complex was determined by single crystal X-ray diffraction analysis. The isotropic and anisotropic EPR spectra of all the complexes prepared were recorded. The obtained EPR parameter values were found to be in agreement with proposed structures.
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