1
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Abstract
Photoactivatable (alternatively, photoremovable, photoreleasable, or photocleavable) protecting groups (PPGs), also known as caged or photocaged compounds, are used to enable non-invasive spatiotemporal photochemical control over the release of species of interest. Recent years have seen the development of PPGs activatable by biologically and chemically benign visible and near-infrared (NIR) light. These long-wavelength-absorbing moieties expand the applicability of this powerful method and its accessibility to non-specialist users. This review comprehensively covers organic and transition metal-containing photoactivatable compounds (complexes) that absorb in the visible- and NIR-range to release various leaving groups and gasotransmitters (carbon monoxide, nitric oxide, and hydrogen sulfide). The text also covers visible- and NIR-light-induced photosensitized release using molecular sensitizers, quantum dots, and upconversion and second-harmonic nanoparticles, as well as release via photodynamic (photooxygenation by singlet oxygen) and photothermal effects. Release from photoactivatable polymers, micelles, vesicles, and photoswitches, along with the related emerging field of photopharmacology, is discussed at the end of the review.
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Affiliation(s)
- Roy Weinstain
- School
of Plant Sciences and Food Security, Faculty of Life Sciences, Tel-Aviv University, Tel-Aviv 6997801, Israel
| | - Tomáš Slanina
- Institute
of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Flemingovo nám. 2, 166 10 Prague, Czech Republic
| | - Dnyaneshwar Kand
- School
of Plant Sciences and Food Security, Faculty of Life Sciences, Tel-Aviv University, Tel-Aviv 6997801, Israel
| | - Petr Klán
- Department
of Chemistry and RECETOX, Faculty of Science, Masaryk University, Kamenice 5, 625 00 Brno, Czech Republic
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2
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González-Delgado JA, Romero MA, Boscá F, Arteaga JF, Pischel U. Visible Light-Gated Organocatalysis Using a Ru II -Photocage. Chemistry 2020; 26:14229-14235. [PMID: 32449554 DOI: 10.1002/chem.202001893] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2020] [Revised: 05/18/2020] [Indexed: 12/23/2022]
Abstract
The light-gated organocatalysis via the release of 4-N,N-dimethylaminopyridine (DMAP) by irradiation of the [Ru(bpy)2 (DMAP)2 ]2+ complex with visible light was investigated. As model reaction the acetylation of benzyl alcohols with acetic anhydride was chosen. The pre-catalyst releases one DMAP molecule on irradiation at wavelengths longer than 455 nm. The photochemical process was characterized by steady-state irradiation and ultrafast transient absorption spectroscopy. The latter enabled the observation of the 3 MLCT state and the spectral features of the penta-coordinated intermediate [Ru(bpy)2 (DMAP)]2+ . The released DMAP catalyzes the acetylation of a wide range of benzyl alcohols with chemical yields of up to 99 %. Control experiments revealed unequivocally that it is the released DMAP which takes the role of the catalyst.
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Affiliation(s)
- José A González-Delgado
- CIQSO-Center for Research in Sustainable Chemistry and, Department of Chemistry, University of Huelva, Campus de El Carmen s/n, 21071, Huelva, Spain
| | - Miguel A Romero
- CIQSO-Center for Research in Sustainable Chemistry and, Department of Chemistry, University of Huelva, Campus de El Carmen s/n, 21071, Huelva, Spain
| | - Francisco Boscá
- Instituto Universitario Mixto de Tecnología Química (ITQ-UPV), Universitat Politècnica de València, Av. de los Naranjos s/n, 46022, Valencia, Spain
| | - Jesús F Arteaga
- CIQSO-Center for Research in Sustainable Chemistry and, Department of Chemistry, University of Huelva, Campus de El Carmen s/n, 21071, Huelva, Spain
| | - Uwe Pischel
- CIQSO-Center for Research in Sustainable Chemistry and, Department of Chemistry, University of Huelva, Campus de El Carmen s/n, 21071, Huelva, Spain
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3
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Abstract
Photodelivery of amino neurotransmitters.
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Affiliation(s)
- Sumin Lee
- Division of Chemical Engineering and Materials Science
- Ewha Womans University
- Seoul 03760
- Korea
| | - Seung Yeon Yi
- Division of Chemical Engineering and Materials Science
- Ewha Womans University
- Seoul 03760
- Korea
| | - Youngmin You
- Division of Chemical Engineering and Materials Science
- Ewha Womans University
- Seoul 03760
- Korea
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4
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Yip AMH, Lo KKW. Luminescent rhenium(I), ruthenium(II), and iridium(III) polypyridine complexes containing a poly(ethylene glycol) pendant or bioorthogonal reaction group as biological probes and photocytotoxic agents. Coord Chem Rev 2018. [DOI: 10.1016/j.ccr.2018.01.021] [Citation(s) in RCA: 88] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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5
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Li A, Yadav R, White JK, Herroon MK, Callahan BP, Podgorski I, Turro C, Scott EE, Kodanko JJ. Illuminating cytochrome P450 binding: Ru(ii)-caged inhibitors of CYP17A1. Chem Commun (Camb) 2018; 53:3673-3676. [PMID: 28304025 DOI: 10.1039/c7cc01459g] [Citation(s) in RCA: 53] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
New Ru(ii)-caged abiraterone complexes were synthesized that exhibit strong absorption in the visible region and release the steroidal CYP17A1 inhibitor abiraterone upon exposure to low energy visible light in buffer and prostate cancer cells. Photoinduced release results in abiraterone binding to its CYP17A1 target in an inhibitory mode.
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Affiliation(s)
- Ao Li
- Department of Chemistry, Wayne State University, Detroit, MI 48202, USA.
| | - Rahul Yadav
- Department of Medicinal Chemistry, University of Michigan, Ann Arbor, Michigan 48109, USA
| | - Jessica K White
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, USA
| | - Mackenzie K Herroon
- Department of Pharmacology, School of Medicine, Wayne State University, Detroit, Michigan 48201, USA
| | - Brian P Callahan
- Department of Chemistry, Binghamton University, Binghamton, New York 13902, USA
| | - Izabela Podgorski
- Department of Pharmacology, School of Medicine, Wayne State University, Detroit, Michigan 48201, USA and Barbara Ann Karmanos Cancer Institute, Detroit, Michigan 48201, USA
| | - Claudia Turro
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, USA
| | - Emily E Scott
- Department of Medicinal Chemistry, University of Michigan, Ann Arbor, Michigan 48109, USA
| | - Jeremy J Kodanko
- Department of Chemistry, Wayne State University, Detroit, MI 48202, USA. and Barbara Ann Karmanos Cancer Institute, Detroit, Michigan 48201, USA
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6
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Poynton FE, Bright SA, Blasco S, Williams DC, Kelly JM, Gunnlaugsson T. The development of ruthenium(ii) polypyridyl complexes and conjugates for in vitro cellular and in vivo applications. Chem Soc Rev 2018; 46:7706-7756. [PMID: 29177281 DOI: 10.1039/c7cs00680b] [Citation(s) in RCA: 284] [Impact Index Per Article: 47.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Ruthenium(ii) [Ru(ii)] polypyridyl complexes have been the focus of intense investigations since work began exploring their supramolecular interactions with DNA. In recent years, there have been considerable efforts to translate this solution-based research into a biological environment with the intention of developing new classes of probes, luminescent imaging agents, therapeutics and theranostics. In only 10 years the field has expanded with diverse applications for these complexes as imaging agents and promising candidates for therapeutics. In light of these efforts this review exclusively focuses on the developments of these complexes in biological systems, both in cells and in vivo, and hopes to communicate to readers the diversity of applications within which these complexes have found use, as well as new insights gained along the way and challenges that researchers in this field still face.
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Affiliation(s)
- Fergus E Poynton
- School of Chemistry and Trinity Biomedical Sciences Institute (TBSI), Trinity College Dublin, The University of Dublin, Dublin 2, Ireland.
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7
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Li A, Turro C, Kodanko JJ. Ru(ii) polypyridyl complexes as photocages for bioactive compounds containing nitriles and aromatic heterocycles. Chem Commun (Camb) 2018; 54:1280-1290. [PMID: 29323683 PMCID: PMC5904840 DOI: 10.1039/c7cc09000e] [Citation(s) in RCA: 59] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Photocaging allows for precise spatiotemporal control over the release of biologically active compounds with light. Most photocaged molecules employ organic photolabile protecting groups; however, biologically active compounds often contain functionalities such as nitriles and aromatic heterocycles that cannot be caged with organic groups. Despite their prevalence, only a few studies have reported successful caging of nitriles and aromatic heterocycles. Recently, Ru(ii)-based photocaging has emerged as a powerful method for the release of bioactive molecules containing these functional groups, in many cases providing high levels of spatial and temporal control over biological activity. This Feature Article discusses recent developments in applying Ru(ii)-based photocaging towards biological problems. Our groups designed and synthesized Ru(ii)-based platforms for the photoinduced delivery of cysteine protease and cytochrome P450 inhibitors in order to achieve selective control over enzyme inhibition. We also reported Ru(ii) photocaging groups derived from higher-denticity ancillary ligands that possess photophysical and photochemical properties distinct from more traditional Ru(ii)-based caging groups. In addition, for the first time, we are able to rapidly synthesize and screen Ru(ii) polypyridyl complexes that elicit desired properties by solid-phase synthesis. Finally, our work also defined steric and orbital mixing effects that are important factors in controlling photoinduced ligand exchange.
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Affiliation(s)
- Ao Li
- Department of Chemistry, Wayne State University, 5101 Cass Ave, Detroit, Michigan 48202, USA.
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8
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9
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Herroon MK, Sharma R, Rajagurubandara E, Turro C, Kodanko JJ, Podgorski I. Photoactivated inhibition of cathepsin K in a 3D tumor model. Biol Chem 2016; 397:571-82. [PMID: 26901495 PMCID: PMC5901740 DOI: 10.1515/hsz-2015-0274] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2015] [Accepted: 02/16/2016] [Indexed: 12/28/2022]
Abstract
Collagenolytic activity of cathepsin K is important for many physiological and pathological processes including osteoclast-mediated bone degradation, macrophage function and fibroblast-mediated matrix remodeling. Here, we report application of a light-activated inhibitor for controlling activity of cathepsin K in a 3D functional imaging assay. Using prostate carcinoma cell line engineered to overexpress cathepsin K, we demonstrate the utility of the proteolytic assay in living tumor spheroids for the evaluation and quantification of the inhibitor effects on cathepsin K-mediated collagen I degradation. Importantly, we also show that utilizing the ruthenium-caged version of a potent nitrile cathepsin K inhibitor (4), cis-[Ru(bpy)2(4)2](BF4)2 (5), offers significant advantage in terms of effective concentration of the inhibitor and especially its light-activated control in the 3D assay. Our results suggest that light activation provides a suitable, attractive approach for spatial and temporal control of proteolytic activity, which remains a critical, unmet need in treatment of human diseases, especially cancer.
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Affiliation(s)
- Mackenzie K. Herroon
- Department of Pharmacology, School of Medicine, Wayne State University, Detroit, MI 48201, USA
| | - Rajgopal Sharma
- Department of Chemistry, Wayne State University, 5101 Cass Ave., Detroit, MI 48202, USA
| | - Erandi Rajagurubandara
- Department of Pharmacology, School of Medicine, Wayne State University, Detroit, MI 48201, USA
| | - Claudia Turro
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, OH 43210, USA
| | - Jeremy J. Kodanko
- Department of Chemistry, Wayne State University, 5101 Cass Ave., Detroit, MI 48202, USA; and Barbara Ann Karmanos Cancer Institute, Detroit, MI 48201, USA
| | - Izabela Podgorski
- Department of Pharmacology, School of Medicine, Wayne State University, Detroit, MI 48201, USA; and Barbara Ann Karmanos Cancer Institute, Detroit, MI 48201, USA
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10
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Tso KKS, Leung KK, Liu HW, Lo KKW. Photoactivatable cytotoxic agents derived from mitochondria-targeting luminescent iridium(iii) poly(ethylene glycol) complexes modified with a nitrobenzyl linkage. Chem Commun (Camb) 2016; 52:4557-60. [DOI: 10.1039/c6cc00918b] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Novel photoactivatable luminescent iridium(iii) complexes were designed to show minimal cytotoxic activity in the dark and become significantly cytotoxic upon irradiation.
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Affiliation(s)
- Karson Ka-Shun Tso
- Department of Biology and Chemistry
- City University of Hong Kong
- Kowloon
- P. R. China
| | - Kam-Keung Leung
- Department of Biology and Chemistry
- City University of Hong Kong
- Kowloon
- P. R. China
| | - Hua-Wei Liu
- Department of Biology and Chemistry
- City University of Hong Kong
- Kowloon
- P. R. China
| | - Kenneth Kam-Wing Lo
- Department of Biology and Chemistry
- City University of Hong Kong
- Kowloon
- P. R. China
- State Key Lab of Millimeter Waves
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11
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Ramalho SD, Sharma R, White JK, Aggarwal N, Chalasani A, Sameni M, Moin K, Vieira PC, Turro C, Kodanko JJ, Sloane BF. Imaging Sites of Inhibition of Proteolysis in Pathomimetic Human Breast Cancer Cultures by Light-Activated Ruthenium Compound. PLoS One 2015; 10:e0142527. [PMID: 26562785 PMCID: PMC4643019 DOI: 10.1371/journal.pone.0142527] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2015] [Accepted: 10/22/2015] [Indexed: 11/21/2022] Open
Abstract
The cysteine protease cathepsin B has been causally linked to progression and metastasis of breast cancers. We demonstrate inhibition by a dipeptidyl nitrile inhibitor (compound 1) of cathepsin B activity and also of pericellular degradation of dye-quenched collagen IV by living breast cancer cells. To image, localize and quantify collagen IV degradation in real-time we used 3D pathomimetic breast cancer models designed to mimic the in vivo microenvironment of breast cancers. We further report the synthesis and characterization of a caged version of compound 1, [Ru(bpy)2(1)2](BF4)2 (compound 2), which can be photoactivated with visible light. Upon light activation, compound 2, like compound 1, inhibited cathepsin B activity and pericellular collagen IV degradation by the 3D pathomimetic models of living breast cancer cells, without causing toxicity. We suggest that caged inhibitor 2 is a prototype for cathepsin B inhibitors that can control both the site and timing of inhibition in cancer.
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Affiliation(s)
- Suelem D. Ramalho
- Department of Chemistry, Federal University of São Carlos, São Carlos, São Paulo, Brazil
| | - Rajgopal Sharma
- Department of Chemistry, Wayne State University, Detroit, Michigan, United States of America
| | - Jessica K. White
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio, United States of America
| | - Neha Aggarwal
- Department of Physiology, School of Medicine, Wayne State University, Detroit, Michigan, United States of America
| | - Anita Chalasani
- Department of Pharmacology, School of Medicine, Wayne State University, Detroit, Michigan, United States of America
| | - Mansoureh Sameni
- Department of Pharmacology, School of Medicine, Wayne State University, Detroit, Michigan, United States of America
| | - Kamiar Moin
- Department of Pharmacology, School of Medicine, Wayne State University, Detroit, Michigan, United States of America
- Department of Oncology, School of Medicine, Wayne State University, Detroit, Michigan, United States of America
| | - Paulo C. Vieira
- Department of Chemistry, Federal University of São Carlos, São Carlos, São Paulo, Brazil
| | - Claudia Turro
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio, United States of America
| | - Jeremy J. Kodanko
- Department of Chemistry, Wayne State University, Detroit, Michigan, United States of America
- * E-mail: (BFS); (JJK)
| | - Bonnie F. Sloane
- Department of Pharmacology, School of Medicine, Wayne State University, Detroit, Michigan, United States of America
- Department of Oncology, School of Medicine, Wayne State University, Detroit, Michigan, United States of America
- * E-mail: (BFS); (JJK)
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12
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Leonidova A, Anstaett P, Pierroz V, Mari C, Spingler B, Ferrari S, Gasser G. Induction of Cytotoxicity through Photorelease of Aminoferrocene. Inorg Chem 2015; 54:9740-8. [DOI: 10.1021/acs.inorgchem.5b01332] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- Anna Leonidova
- Department of Chemistry, University of Zurich, Winterthurerstrasse 190, CH-8057 Zurich, Switzerland
| | - Philipp Anstaett
- Department of Chemistry, University of Zurich, Winterthurerstrasse 190, CH-8057 Zurich, Switzerland
| | - Vanessa Pierroz
- Department of Chemistry, University of Zurich, Winterthurerstrasse 190, CH-8057 Zurich, Switzerland
- Institute
of Molecular Cancer Research, University of Zurich, Winterthurerstrasse
190, CH-8057 Zurich, Switzerland
| | - Cristina Mari
- Department of Chemistry, University of Zurich, Winterthurerstrasse 190, CH-8057 Zurich, Switzerland
| | - Bernhard Spingler
- Department of Chemistry, University of Zurich, Winterthurerstrasse 190, CH-8057 Zurich, Switzerland
| | - Stefano Ferrari
- Institute
of Molecular Cancer Research, University of Zurich, Winterthurerstrasse
190, CH-8057 Zurich, Switzerland
| | - Gilles Gasser
- Department of Chemistry, University of Zurich, Winterthurerstrasse 190, CH-8057 Zurich, Switzerland
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13
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Tu YJ, Mazumder S, Endicott JF, Turro C, Kodanko JJ, Schlegel HB. Selective Photodissociation of Acetonitrile Ligands in Ruthenium Polypyridyl Complexes Studied by Density Functional Theory. Inorg Chem 2015; 54:8003-11. [PMID: 26244447 DOI: 10.1021/acs.inorgchem.5b01202] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Metal complexes that release ligands upon photoexcitation are important tools for biological research and show great potential as highly specific therapeutics. Upon excitation with visible light, [Ru(TQA)(MeCN)2](2+) [TQA = tris(2-quinolinylmethyl)amine] exchanges one of the two acetonitriles (MeCNs), whereas [Ru(DPAbpy)MeCN](2+) [DPAbpy = N-(2,2'-bipyridin-6-yl)-N,N-bis(pyridin-2-ylmethyl)amine] does not release MeCN. Furthermore, [Ru(TQA)(MeCN)2](2+) is highly selective for release of the MeCN that is perpendicular to the plane of the two axial quinolines. Density functional theory calculations provide a clear explanation for the photodissociation behavior of these two complexes. Excitation by visible light and intersystem crossing leads to a six-coordinate (3)MLCT state. Dissociation of acetonitrile can occur after internal conversion to a dissociative (3)MC state, which has an occupied dσ* orbital that interacts in an antibonding fashion with acetonitrile. For [Ru(TQA)(MeCN)2](2+), the dissociative (3)MC state is lower than the (3)MLCT state. In contrast, the (3)MC state of [Ru(DPAbpy)MeCN](2+) that releases acetonitrile has an energy higher than that of the (3)MLCT state, indicating dissociation is unfavorable. These results are consistent with the experimental observations that efficient photodissociation of acetonitrile occurs for [Ru(TQA)(MeCN)2](2+) but not for [Ru(DPAbpy)MeCN](2+). For the release of the MeCN ligand in [Ru(TQA)(MeCN)2](2+) that is perpendicular to the axial quinoline rings, the (3)MLCT state has an occupied quinoline π* orbital that can interact with a dσ* Ru-NCCH3 antibonding orbital as the Ru-NCCH3 bond is stretched and the quinolines bend toward the departing acetonitrile. This reduces the barrier for the formation of the dissociative (3)MC state, leading to the selective photodissociation of this acetonitrile. By contrast, when the acetonitrile is in the plane of the quinolines or bpy, no interaction occurs between the ligand π* orbital and the dσ* Ru-NCCH3 orbital, resulting in high barriers for conversion to the corresponding (3)MC structures and no release of acetonitrile.
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Affiliation(s)
- Yi-Jung Tu
- †Department of Chemistry, Wayne State University, 5101 Cass Avenue, Detroit, Michigan 48202, United States
| | - Shivnath Mazumder
- †Department of Chemistry, Wayne State University, 5101 Cass Avenue, Detroit, Michigan 48202, United States
| | - John F Endicott
- †Department of Chemistry, Wayne State University, 5101 Cass Avenue, Detroit, Michigan 48202, United States
| | - Claudia Turro
- ‡Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, United States
| | - Jeremy J Kodanko
- †Department of Chemistry, Wayne State University, 5101 Cass Avenue, Detroit, Michigan 48202, United States
| | - H Bernhard Schlegel
- †Department of Chemistry, Wayne State University, 5101 Cass Avenue, Detroit, Michigan 48202, United States
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Griepenburg JC, Rapp TL, Carroll PJ, Eberwine J, Dmochowski IJ. Ruthenium-Caged Antisense Morpholinos for Regulating Gene Expression in Zebrafish Embryos. Chem Sci 2015; 6:2342-2346. [PMID: 26023327 PMCID: PMC4443914 DOI: 10.1039/c4sc03990d] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2014] [Accepted: 01/29/2015] [Indexed: 11/25/2022] Open
Abstract
Photochemical approaches afford high spatiotemporal control over molecular structure and function, for broad applications in materials and biological science. Here, we present the first example of a visible light responsive ruthenium-based photolinker, Ru(bipyridine)2(3-ethynylpyridine)2 (RuBEP), which was reacted stoichiometrically with a 25mer DNA or morpholino (MO) oligonucleotide functionalized with 3' and 5' terminal azides, via Cu(I)-mediated [3+2] Huisgen cycloaddition reactions. RuBEP-caged circular morpholinos (Ru-MOs) targeting two early developmental zebrafish genes, chordin and notail, were synthesized and tested in vivo. One-cell-stage zebrafish embryos microinjected with Ru-MO and incubated in the dark for 24 h developed normally, consistent with caging, whereas irradiation at 450 nm dissociated one 3-ethynylpyridine ligand (ϕ = 0.33) and uncaged the MO to achieve gene knockdown. As demonstrated, Ru photolinkers provide a versatile method for controlling structure and function of biopolymers.
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Affiliation(s)
- Julianne C. Griepenburg
- Department of Chemistry , University of Pennsylvania , 231 South 34th Street , Philadelphia , Pennsylvania 19104 , USA .
| | - Teresa L. Rapp
- Department of Chemistry , University of Pennsylvania , 231 South 34th Street , Philadelphia , Pennsylvania 19104 , USA .
| | - Patrick J. Carroll
- Department of Chemistry , University of Pennsylvania , 231 South 34th Street , Philadelphia , Pennsylvania 19104 , USA .
| | - James Eberwine
- Department of Systems Pharmacology and Experimental Therapeutics , Perelman School of Medicine , University of Pennsylvania , 37 John Morgan Building, 3620 Hamilton Walk , Philadelphia , Pennsylvania 19104 , USA
| | - Ivan J. Dmochowski
- Department of Chemistry , University of Pennsylvania , 231 South 34th Street , Philadelphia , Pennsylvania 19104 , USA .
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15
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Sharma R, Knoll JD, Ancona N, Martin PD, Turro C, Kodanko JJ. Solid-phase synthesis as a platform for the discovery of new ruthenium complexes for efficient release of photocaged ligands with visible light. Inorg Chem 2015; 54:1901-11. [PMID: 25611351 DOI: 10.1021/ic502791y] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Ruthenium-based photocaging groups have important applications as biological tools and show great potential as therapeutics. A method was developed to rapidly synthesize, screen, and identify ruthenium-based caging groups that release nitriles upon irradiation with visible light. A diverse library of tetra- and pentadentate ligands was synthesized on polystyrene resin. Ruthenium complexes of the general formula [Ru(L)(MeCN)n](m+) (n = 1-3, m = 1-2) were generated from these ligands on solid phase and then cleaved from resin for photochemical analysis. Data indicate a wide range of spectral tuning and reactivity with visible light. Three complexes that showed strong absorbance in the visible range were synthesized by solution phase for comparison. Photochemical behavior of solution- and solid-phase complexes was in good agreement, confirming that the library approach is useful in identifying candidates with desired photoreactivity in short order, avoiding time-consuming chromatography and compound purification.
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Affiliation(s)
- Rajgopal Sharma
- Department of Chemistry, Wayne State University , 5101 Cass Avenue, Detroit, Michigan 48202, United States
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16
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Zhou J, Fang C, Liu Y, Zhao Y, Zhang N, Liu X, Wang F, Shangguan D. Visible-light-induced cleavage of 4-α-amino acid substituted naphthalimides and its application in DNA photocleavage. Org Biomol Chem 2015; 13:3931-5. [DOI: 10.1039/c5ob00302d] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
4-α-Amino acid substituted naphthalimides can be photocleaved at the C–N bond between the 4-amino and the amino acid residue under visible light irradiation, releasing a fluorophore, 4-aminonaphthalimide.
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Affiliation(s)
- Jin Zhou
- Beijing National Laboratory for Molecular Sciences
- Key Laboratory of Analytical Chemistry for Living Biosystems
- Institute of Chemistry
- Chinese Academy of Sciences
- Beijing
| | - Canliang Fang
- Beijing National Laboratory for Molecular Sciences
- Key Laboratory of Analytical Chemistry for Living Biosystems
- Institute of Chemistry
- Chinese Academy of Sciences
- Beijing
| | - Ying Liu
- Beijing National Laboratory for Molecular Sciences
- Key Laboratory of Analytical Chemistry for Living Biosystems
- Institute of Chemistry
- Chinese Academy of Sciences
- Beijing
| | - Yao Zhao
- Beijing National Laboratory for Molecular Sciences
- Key Laboratory of Analytical Chemistry for Living Biosystems
- Institute of Chemistry
- Chinese Academy of Sciences
- Beijing
| | - Nan Zhang
- Beijing National Laboratory for Molecular Sciences
- Key Laboratory of Analytical Chemistry for Living Biosystems
- Institute of Chemistry
- Chinese Academy of Sciences
- Beijing
| | - Xiangjun Liu
- Beijing National Laboratory for Molecular Sciences
- Key Laboratory of Analytical Chemistry for Living Biosystems
- Institute of Chemistry
- Chinese Academy of Sciences
- Beijing
| | - Fuyi Wang
- Beijing National Laboratory for Molecular Sciences
- Key Laboratory of Analytical Chemistry for Living Biosystems
- Institute of Chemistry
- Chinese Academy of Sciences
- Beijing
| | - Dihua Shangguan
- Beijing National Laboratory for Molecular Sciences
- Key Laboratory of Analytical Chemistry for Living Biosystems
- Institute of Chemistry
- Chinese Academy of Sciences
- Beijing
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17
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Abstract
The use of visible light to produce highly selective and potent drugs through photodynamic therapy (PDT) holds much potential in the treatment of cancer. PDT agents can be designed to follow an O2-dependent mechanism by producing highly reactive species such as 1O2 and/or an O2 independent mechanism through processes such as excited state electron transfer, covalent binding to DNA or photoinduced drug delivery. Ru(II)-polypyridyl and Rh2(II,II) complexes represent an important class of compounds that can be tailored to exhibit desired photophysical properties and photochemical reactivity by judicious selection of the ligand set. Complexes with relatively long-lived excited states and planar, intercalating ligands localize on the DNA strand and photocleave DNA through 1O2 production or guanine oxidation by the excited state of the chromophore. Photoinduced ligand substitution occurs through the population of triplet metal centered (3MC) excited states and facilitates covalent binding of the metal complex to DNA in a mode similar to cisplatin. Ligand photodissociation also provides a route to selective drug delivery. The ability to construct metal complexes with desired light absorbing and excited state properties by ligand variation enables the design of PDT agents that can potentially provide combination therapy from a single metal complex.
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Affiliation(s)
- Jessica D. Knoll
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, OH 43210, USA
| | - Claudia Turro
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, OH 43210, USA
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Frei A, Rubbiani R, Tubafard S, Blacque O, Anstaett P, Felgenträger A, Maisch T, Spiccia L, Gasser G. Synthesis, characterization, and biological evaluation of new Ru(II) polypyridyl photosensitizers for photodynamic therapy. J Med Chem 2014; 57:7280-92. [PMID: 25121347 DOI: 10.1021/jm500566f] [Citation(s) in RCA: 136] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Two Ru(II) polypyridyl complexes, Ru(DIP)2(bdt) (1) and [Ru(dqpCO2Me)(ptpy)](2+) (2) (DIP = 4,7-diphenyl-1,10-phenanthroline, bdt = 1,2-benzenedithiolate, dqpCO2Me = 4-methylcarboxy-2,6-di(quinolin-8-yl)pyridine), ptpy = 4'-phenyl-2,2':6',2″-terpyridine) have been investigated as photosensitizers (PSs) for photodynamic therapy (PDT). In our experimental settings, the phototoxicity and phototoxic index (PI) of 2 (IC50(light): 25.3 μM, 420 nm, 6.95 J/cm(2); PI >4) and particularly of 1 (IC50(light): 0.62 μM, 420 nm, 6.95 J/cm(2); PI: 80) are considerably superior compared to the two clinically approved PSs porfimer sodium and 5-aminolevulinic acid. Cellular uptake and distribution of these complexes was investigated by confocal microscopy (1) and by inductively coupled plasma mass spectrometry (1 and 2). Their phototoxicity was also determined against the Gram-(+) Staphylococcus aureus and Gram-(-) Escherichia coli for potential antimicrobial PDT (aPDT) applications. Both complexes showed significant aPDT activity (420 nm, 8 J/cm(2)) against Gram-(+) (S. aureus; >6 log10 CFU reduction) and, for 2, also against Gram-(-) E. coli (>4 log10 CFU reduction).
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Affiliation(s)
- Angelo Frei
- Department of Chemistry, University of Zurich , Winterthurerstrasse 190, CH-8057 Zurich, Switzerland
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Leonidova A, Pierroz V, Rubbiani R, Lan Y, Schmitz AG, Kaech A, Sigel RKO, Ferrari S, Gasser G. Photo-induced uncaging of a specific Re(i) organometallic complex in living cells. Chem Sci 2014. [DOI: 10.1039/c3sc53550a] [Citation(s) in RCA: 94] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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Respondek T, Sharma R, Herroon MK, Garner RN, Knoll JD, Cueny E, Turro C, Podgorski I, Kodanko JJ. Inhibition of cathepsin activity in a cell-based assay by a light-activated ruthenium compound. ChemMedChem 2014; 9:1306-15. [PMID: 24729544 PMCID: PMC4095795 DOI: 10.1002/cmdc.201400081] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2014] [Indexed: 12/12/2022]
Abstract
Light-activated inhibition of cathepsin activity was demonstrated in a cell-based assay. Inhibitors of cathepsin K, Cbz-Leu-NHCH2 CN (2) and Cbz-Leu-Ser(OBn)-CN (3), were caged within the complexes cis-[Ru(bpy)2 (2)2 ]Cl2 (4) and cis-[Ru(bpy)2 (3)2 ](BF4 )2 (5) (bpy=2,2'-bipyridine) as 1:1 mixtures of Δ and Λ stereoisomers. Complexes 4 and 5 were characterized by (1) H NMR, IR, and UV/Vis spectroscopies and electrospray mass spectrometry. Photochemical experiments confirm that 4 releases two molecules of 2 upon exposure to visible light for 15 min, whereas release of 3 by 5 requires longer irradiation times. IC50 determinations against purified cathepsin K under light and dark conditions with 4 and 5 confirm that inhibition is enhanced from 35- to 88-fold, respectively, upon irradiation with visible light. No apparent toxicity was observed for 4 in the absence or presence of irradiation in bone marrow macrophage (BMM) or PC3 cells, as determined by MTT assays, at concentrations up to 10 μM. Compound 5 is well tolerated at lower concentrations (<1 μM), but does show growth-inhibitory effects at higher concentrations. Confocal microscopy experiments show that 4 decreases intracellular cathepsin activity in osteoclasts with light activation. These results support the further development of caged nitrile-based inhibitors as chemical tools for investigating spatial aspects of proteolysis within living systems.
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Affiliation(s)
- Tomasz Respondek
- Department of Chemistry, Wayne State University, 5101 Cass Avenue, Detroit, MI 48202 (USA)
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Mosquera J, Sánchez MI, Vázquez ME, Mascareñas JL. Ruthenium bipyridyl complexes as photocleavable dimerizers: deactivation of DNA-binding peptides using visible light. Chem Commun (Camb) 2014; 50:10975-8. [DOI: 10.1039/c4cc04512b] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Turning off DNA binding by visible light.
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Affiliation(s)
- Jesús Mosquera
- Centro Singular de Investigación en Química Biolóxica e Materiais Moleculares (CIQUS) and Departamento de Química Orgánica
- Campus Vida
- Universidade de Santiago de Compostela
- , Spain
| | - Mateo I. Sánchez
- Centro Singular de Investigación en Química Biolóxica e Materiais Moleculares (CIQUS) and Departamento de Química Orgánica
- Campus Vida
- Universidade de Santiago de Compostela
- , Spain
| | - M. Eugenio Vázquez
- Centro Singular de Investigación en Química Biolóxica e Materiais Moleculares (CIQUS) and Departamento de Química Orgánica
- Campus Vida
- Universidade de Santiago de Compostela
- , Spain
| | - José L. Mascareñas
- Centro Singular de Investigación en Química Biolóxica e Materiais Moleculares (CIQUS) and Departamento de Química Orgánica
- Campus Vida
- Universidade de Santiago de Compostela
- , Spain
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Filevich O, Zayat L, Baraldo LM, Etchenique R. Long Wavelength Phototriggering: Ruthenium-Based Caged Compounds. Luminescent and Photoactive Transition Metal Complexes as Biomolecular Probes and Cellular Reagents 2014. [DOI: 10.1007/430_2014_169] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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Fournier L, Aujard I, Le Saux T, Maurin S, Beaupierre S, Baudin J, Jullien L. Coumarinylmethyl Caging Groups with Redshifted Absorption. Chemistry 2013; 19:17494-507. [DOI: 10.1002/chem.201302630] [Citation(s) in RCA: 87] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2013] [Revised: 08/16/2013] [Indexed: 12/22/2022]
Affiliation(s)
- Ludovic Fournier
- Ecole Normale Supérieure, Département de Chimie, UMR CNRS‐ENS‐UPMC, Paris 06 8640 PASTEUR, 24, rue Lhomond, 75231 Paris Cedex 05 (France)
| | - Isabelle Aujard
- Ecole Normale Supérieure, Département de Chimie, UMR CNRS‐ENS‐UPMC, Paris 06 8640 PASTEUR, 24, rue Lhomond, 75231 Paris Cedex 05 (France)
| | - Thomas Le Saux
- Ecole Normale Supérieure, Département de Chimie, UMR CNRS‐ENS‐UPMC, Paris 06 8640 PASTEUR, 24, rue Lhomond, 75231 Paris Cedex 05 (France)
- UPMC Paris 06, 4, Place Jussieu, 75232 Paris Cedex 05 (France)
| | - Sylvie Maurin
- Ecole Normale Supérieure, Département de Chimie, UMR CNRS‐ENS‐UPMC, Paris 06 8640 PASTEUR, 24, rue Lhomond, 75231 Paris Cedex 05 (France)
| | - Sandra Beaupierre
- Ecole Normale Supérieure, Département de Chimie, UMR CNRS‐ENS‐UPMC, Paris 06 8640 PASTEUR, 24, rue Lhomond, 75231 Paris Cedex 05 (France)
| | - Jean‐Bernard Baudin
- Ecole Normale Supérieure, Département de Chimie, UMR CNRS‐ENS‐UPMC, Paris 06 8640 PASTEUR, 24, rue Lhomond, 75231 Paris Cedex 05 (France)
| | - Ludovic Jullien
- Ecole Normale Supérieure, Département de Chimie, UMR CNRS‐ENS‐UPMC, Paris 06 8640 PASTEUR, 24, rue Lhomond, 75231 Paris Cedex 05 (France)
- UPMC Paris 06, 4, Place Jussieu, 75232 Paris Cedex 05 (France)
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Sgambellone MA, David A, Garner RN, Dunbar KR, Turro C. Cellular toxicity induced by the photorelease of a caged bioactive molecule: design of a potential dual-action Ru(II) complex. J Am Chem Soc 2013; 135:11274-82. [PMID: 23819591 DOI: 10.1021/ja4045604] [Citation(s) in RCA: 181] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The series [Ru(tpy)(CH3CN)3](2+) (1), cis-[Ru(tpy)(CH3CN)2Cl](+) (2), and [Ru(tpy)(5CNU)3](2+) (3), where tpy = 2,2':6',2″-terpyridine and 5CNU = 5-cyanouracil, was synthesized, and their photochemical properties were investigated for use as potential photodynamic therapy (PDT) agents. When irradiated with visible light, 1-3 exhibit efficient exchange of the axial CH3CN or 5CNU ligand with H2O solvent molecules. Complexes 1-3 also exhibit photoinitiated binding to DNA when irradiated with λirr ≥ 395 nm light, and DNA binding can be accessed for 2 with λirr > 645 nm, well within the PDT window. Since 3 binds DNA and simultaneously releases biologically active 5CNU, it has the potential to be a dual-action therapeutic agent. Indeed, 3 is cytotoxic upon irradiation with visible light, whereas 1 is not under similar experimental conditions. The lack of toxicity imparted by 1 is explained by the exchange of only one CH3CN ligand in the complex under the irradiation conditions used for the cellular studies. Strategies are being sought to increase the quantum yields of ligand exchange and the cellular penetration of these compounds.
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Affiliation(s)
- Mark A Sgambellone
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, USA
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Klán P, Šolomek T, Bochet CG, Blanc A, Givens R, Rubina M, Popik V, Kostikov A, Wirz J. Photoremovable protecting groups in chemistry and biology: reaction mechanisms and efficacy. Chem Rev 2013; 113:119-91. [PMID: 23256727 PMCID: PMC3557858 DOI: 10.1021/cr300177k] [Citation(s) in RCA: 1214] [Impact Index Per Article: 110.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2012] [Indexed: 02/06/2023]
Affiliation(s)
- Petr Klán
- Department of Chemistry, Faculty of Science, Masaryk University, Kamenice 5, 625 00 Brno, Czech Republic.
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Respondek T, Garner RN, Herroon MK, Podgorski I, Turro C, Kodanko JJ. Light activation of a cysteine protease inhibitor: caging of a peptidomimetic nitrile with Ru(II)(bpy)2. J Am Chem Soc 2011; 133:17164-7. [PMID: 21973207 DOI: 10.1021/ja208084s] [Citation(s) in RCA: 114] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
A novel method for caging protease inhibitors is described. The complex [Ru(II)(bpy)(2)(1)(2)](PF(6))(2) (2) was prepared from the nitrile-based peptidomimetic inhibitor Ac-Phe-NHCH(2)CN (1). (1)H NMR, UV-vis, and IR spectroscopic and mass spectrometric data confirmed that 2 equiv of inhibitor 1 bind to Ru(II) through the nitrile functional group. Complex 2 shows excellent stability in aqueous solution in the dark and fast release of 1 upon irradiation with visible light. As a result of binding to the Ru(II) center, the nitriles of complex 2 are caged, and 2 does not act as a potent enzyme inhibitor. However, when 2 is irradiated, it releases 1, which inhibits the cysteine proteases papain and cathepsins B, K and L up to 2 times more potently than 1 alone. Ratios of the IC(50) values in the dark versus in the light ranged from 6:1 to 33:1 for inhibition by 2 against isolated enzymes and in human cell lysates, confirming that a high level of photoinduced enzyme inhibition can be obtained using this method.
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Affiliation(s)
- Tomasz Respondek
- Department of Chemistry, Wayne State University, Detroit, Michigan 48202, USA
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Schatzschneider U. PhotoCORMs: Light-triggered release of carbon monoxide from the coordination sphere of transition metal complexes for biological applications. Inorganica Chim Acta 2011. [DOI: 10.1016/j.ica.2011.02.068] [Citation(s) in RCA: 218] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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Salassa L, Garino C, Salassa G, Nervi C, Gobetto R, Lamberti C, Gianolio D, Bizzarri R, Sadler PJ. Ligand-selective photodissociation from [Ru(bpy)(4AP)4]2+: a spectroscopic and computational study. Inorg Chem 2010; 48:1469-81. [PMID: 19149466 DOI: 10.1021/ic8015436] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The new complex [Ru(bpy)(4AP)(4)](2+) (1), where bpy = 2,2'-bipyridine and 4AP = 4-aminopyridine, undergoes selective photodissociation of two 4APs upon light excitation of the metal-ligand-to-ligand charge-transfer (MLLCT) band at 510 nm. The photoproducts of the reaction are mer-[Ru(bpy)(4AP)(3)(H(2)O)](2+) (2a) and trans-(4AP)[Ru(bpy)(4AP)(2)(H(2)O)(2)](2+) (3a). Photodissociation occurs in two consecutive steps with quantum yields of phi(1) = (6.1 +/- 1.0) x 10(-3) and phi(2) = (1.7 +/- 0.1) x 10(-4), respectively. Complex 1 was characterized by combined spectroscopic and theoretical techniques. EXAFS experiments at the Ru K-edge (22 117 eV) of 1 in an aqueous solution gave a Ru-N distance of 2.09 +/- 0.01 A. Photoproducts were characterized by electronic spectroscopy, 1D and 2D NMR, and mass spectrometry. Singlet and triplet excited states of 1 were studied by density functional theory (DFT) and time-dependent DFT for characterizing the optical properties of the complex. In the singlet state, (1)MC (metal-centered) dissociative states lie 0.65 eV above the main (1)MLLCT transition in the visible region of the UV-vis absorption spectrum. In the triplet state, the energy difference between these states is not reduced. However, potential energy curves of singlet and triplet excited states of 1 along the Ru-N(axial 4AP) and Ru-N(equatorial 4AP) stretching coordinates show that the release of the first 4AP may occur from the triplet state by mixing of (3)MLLCT and (3)MC dissociative states. This mixing is favored when the Ru-N(equatorial 4AP) bond is elongated, explaining the formation of the photoproduct 2a.
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Affiliation(s)
- Luca Salassa
- Department of Chemistry, University of Warwick, Gibbet Hill Road, Coventry CV4 7AL, United Kingdom
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Ciesienski KL, Hyman LM, Yang DT, Haas KL, Dickens MG, Holbrook RJ, Franz KJ. A Photo-Caged Platinum(II) Complex That Increases Cytotoxicity upon Light Activation. Eur J Inorg Chem 2010. [DOI: 10.1002/ejic.201000098] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Affiliation(s)
- Ulrich Schatzschneider
- Lehrstuhl für Anorganische Chemie I – Bioanorganische Chemie and Research Department Interfacial Systems Chemistry (RD IFSC), Ruhr‐Universität Bochum NC 3/74, Universitätsstr. 150, 44801 Bochum, Germany, Fax: +49‐234‐32‐14378
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Affiliation(s)
- Kathryn L Haas
- Department of Chemistry, Duke University, 124 Science Drive, Durham, North Carolina 27708-0346, USA
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