1
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Martins TJ, Parisi C, Pinto JG, Brambilla IDPR, Melilli B, Aleo D, Ferreira-Strixino J, Sortino S. Simultaneous photoactivation of a fluoroquinolone antibiotic and nitric oxide with fluorescence reporting. J Mater Chem B 2024; 12:7626-7634. [PMID: 39005154 DOI: 10.1039/d4tb01291g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/16/2024]
Abstract
The achievement of smart pharmaceuticals whose bioactivity can be spatiotemporally controlled by light stimuli is known as photopharmacology, an emerging area aimed at improving the therapeutic outcome and minimizing side effects. This is especially attractive for antibiotics, for which the inevitable development of multidrug resistance and the dwindling of new clinically approved drugs represent the main drawbacks. Here, we show that nitrosation of the fluoroquinolone norfloxacin (NF), a broad-spectrum antibiotic, leads to the nitrosated bioconjugate NF-NO, which is inactive at the typical minimum inhibitory concentration of NF. Irradiation of NF-NO with visible blue light triggers the simultaneous release of NF and nitric oxide (NO). The photouncaging process is accompanied by the revival of the typical fluorescence emission of NF, quenched in NF-NO, which acts as an optical reporter. This permits the real-time monitoring of the photouncaging process, even within bacteria cells where antibacterial activity is switched on exclusively upon light irradiation. The mechanism of photorelease seems to occur through a two-step hopping electron transfer mediated by the lowest triplet state of NF-NO and the phosphate buffer ions or aminoacids such as tyrosine. Considering the well-known role of NO as an "unconventional" antibacterial, the NF-NO conjugate may represent a potential bimodal antibacterial weapon activatable on demand with high spatio-temporal control.
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Affiliation(s)
- Tassia J Martins
- PhotoChemLab, Department of Drug and Health Sciences, University of Catania, I-95125, Italy.
| | - Cristina Parisi
- PhotoChemLab, Department of Drug and Health Sciences, University of Catania, I-95125, Italy.
| | - Juliana Guerra Pinto
- Laboratory of Photobiology Applied to Health, Research and Development Institute, University of Vale do Paraíba, Urbanova I-2911, Brazil
| | | | | | - Danilo Aleo
- MEDIVIS S.r.l., Tremestieri Etneo, 95030 Catania, Italy
| | - Juliana Ferreira-Strixino
- Laboratory of Photobiology Applied to Health, Research and Development Institute, University of Vale do Paraíba, Urbanova I-2911, Brazil
| | - Salvatore Sortino
- PhotoChemLab, Department of Drug and Health Sciences, University of Catania, I-95125, Italy.
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2
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Dissanayake KC, Yuan D, Winter AH. Structure-Photoreactivity Studies of BODIPY Photocages: Limitations of the Activation Barrier for Optimizing Photoreactions. J Org Chem 2024; 89:6740-6748. [PMID: 38695507 PMCID: PMC11198865 DOI: 10.1021/acs.joc.3c02980] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/18/2024]
Abstract
BODIPY photocages are photoreactive chromophores that release covalently linked cargo upon absorption of visible light. Here, we used computations of the T1 photoheterolysis barrier to ascertain whether a computational approach could assist in a priori structure design by identifying new structures with higher quantum yields of photorelease. The electronic structure-photoreactivity relationships were elucidated for boron-substituted and core-functionalized 2-substituted BODIPY photocages as well as aryl substitutions at the meso-methyl position. Although there is a clear trend for the 2-substituted derivatives, with donor-substituted derivatives featuring both lower computed barriers and higher experimental quantum yields, no trend in the quantum yield with the computed activation barrier is found for the meso-methyl-substituted or boron-substituted derivatives. The lack of a correlation between the experimental quantum yield with the computed barrier in the latter two substitution cases is attributed to the substituents having larger effects on the rates of competing channels (internal conversion and competitive photoreactions) than on the rate of the photoheterolysis channel. Thus, although in some cases computed photoreaction barriers can aid in identifying structures with higher quantum yields, the ignored impacts of how changing the structure affects the rates of competing photophysical/photochemical channels limit the effectiveness of this single-parameter approach.
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Affiliation(s)
- Komadhie C Dissanayake
- Department of Chemistry, Iowa State University, 1608 Gilman Hall, Ames, Iowa 50010, United States
| | - Ding Yuan
- Department of Chemistry, Iowa State University, 1608 Gilman Hall, Ames, Iowa 50010, United States
| | - Arthur H Winter
- Department of Chemistry, Iowa State University, 1608 Gilman Hall, Ames, Iowa 50010, United States
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3
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Schulte AM, Alachouzos G, Szymanski W, Feringa BL. The fate of the contact ion pair determines the photochemistry of coumarin-based photocleavable protecting groups. Chem Sci 2024; 15:2062-2073. [PMID: 38332822 PMCID: PMC10848663 DOI: 10.1039/d3sc05725a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2023] [Accepted: 01/05/2024] [Indexed: 02/10/2024] Open
Abstract
Photocleavable protecting groups (PPGs) enable the precise spatiotemporal control over the release of a payload of interest, in particular a bioactive substance, through light irradiation. A crucial parameter that determines the practical applicability of PPGs is the efficiency of payload release, largely governed by the quantum yield of photolysis (QY). Understanding which parameters determine the QY will prove crucial for engineering improved PPGs and their effective future applications, especially in the emerging field of photopharmacology. The Contact Ion Pair (CIP) has been recognized as an important intermediate in the uncaging process, but the key influence of its fate on the quantum yield has not been explored yet, limiting our ability to design improved PPGs. Here, we demonstrate that the CIP escape mechanism of PPGs is crucial for determining their payload- and solvent-dependent photolysis QY, and illustrate that an intramolecular type of CIP escape is superior over diffusion-dependent CIP escape. Furthermore, we report a strong correlation of the photolysis QY of a range of coumarin PPGs with the DFT-calculated height of all three energy barriers involved in the photolysis reaction, despite the vastly different mechanisms of CIP escape that these PPGs exhibit. Using the insights obtained through our analysis, we were able to predict the photolysis QY of a newly designed PPG with particularly high accuracy. The level of understanding of the factors determining the QY of PPGs presented here will move the ever-expanding field of PPG applications forward and provides a blueprint for the development of PPGs with QYs that are independent of payload-topology and solvent polarity.
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Affiliation(s)
- Albert Marten Schulte
- Centre for Systems Chemistry, Stratingh Institute for Chemistry, Faculty for Science and Engineering, University of Groningen Nijenborgh 4 9747 AG Groningen The Netherlands
| | - Georgios Alachouzos
- Centre for Systems Chemistry, Stratingh Institute for Chemistry, Faculty for Science and Engineering, University of Groningen Nijenborgh 4 9747 AG Groningen The Netherlands
| | - Wiktor Szymanski
- Centre for Systems Chemistry, Stratingh Institute for Chemistry, Faculty for Science and Engineering, University of Groningen Nijenborgh 4 9747 AG Groningen The Netherlands
- Department of Radiology, Medical Imaging Center, University Medical Center Groningen, University of Groningen Hanzeplein 1 9713 GZ Groningen The Netherlands
| | - Ben L Feringa
- Centre for Systems Chemistry, Stratingh Institute for Chemistry, Faculty for Science and Engineering, University of Groningen Nijenborgh 4 9747 AG Groningen The Netherlands
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4
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Shrestha P, Kand D, Weinstain R, Winter AH. meso-Methyl BODIPY Photocages: Mechanisms, Photochemical Properties, and Applications. J Am Chem Soc 2023; 145:17497-17514. [PMID: 37535757 DOI: 10.1021/jacs.3c01682] [Citation(s) in RCA: 17] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/05/2023]
Abstract
meso-methyl BODIPY photocages have recently emerged as an exciting new class of photoremovable protecting groups (PPGs) that release leaving groups upon absorption of visible to near-infrared light. In this Perspective, we summarize the development of these PPGs and highlight their critical photochemical properties and applications. We discuss the absorption properties of the BODIPY PPGs, structure-photoreactivity studies, insights into the photoreaction mechanism, the scope of functional groups that can be caged, the chemical synthesis of these structures, and how substituents can alter the water solubility of the PPG and direct the PPG into specific subcellular compartments. Applications that exploit the unique optical and photochemical properties of BODIPY PPGs are also discussed, from wavelength-selective photoactivation to biological studies to photoresponsive organic materials and photomedicine.
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Affiliation(s)
- Pradeep Shrestha
- Department of Chemistry, Iowa State University, Ames, Iowa 50010, United States
| | - Dnyaneshwar Kand
- School of Plant Sciences and Food Security, Tel-Aviv University, Tel-Aviv 6997801, Israel
| | - Roy Weinstain
- School of Plant Sciences and Food Security, Tel-Aviv University, Tel-Aviv 6997801, Israel
| | - Arthur H Winter
- Department of Chemistry, Iowa State University, Ames, Iowa 50010, United States
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5
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Kauser A, Parisini E, Suarato G, Castagna R. Light-Based Anti-Biofilm and Antibacterial Strategies. Pharmaceutics 2023; 15:2106. [PMID: 37631320 PMCID: PMC10457815 DOI: 10.3390/pharmaceutics15082106] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Revised: 07/29/2023] [Accepted: 08/02/2023] [Indexed: 08/27/2023] Open
Abstract
Biofilm formation and antimicrobial resistance pose significant challenges not only in clinical settings (i.e., implant-associated infections, endocarditis, and urinary tract infections) but also in industrial settings and in the environment, where the spreading of antibiotic-resistant bacteria is on the rise. Indeed, developing effective strategies to prevent biofilm formation and treat infections will be one of the major global challenges in the next few years. As traditional pharmacological treatments are becoming inadequate to curb this problem, a constant commitment to the exploration of novel therapeutic strategies is necessary. Light-triggered therapies have emerged as promising alternatives to traditional approaches due to their non-invasive nature, precise spatial and temporal control, and potential multifunctional properties. Here, we provide a comprehensive overview of the different biofilm formation stages and the molecular mechanism of biofilm disruption, with a major focus on the quorum sensing machinery. Moreover, we highlight the principal guidelines for the development of light-responsive materials and photosensitive compounds. The synergistic effects of combining light-triggered therapies with conventional treatments are also discussed. Through elegant molecular and material design solutions, remarkable results have been achieved in the fight against biofilm formation and antibacterial resistance. However, further research and development in this field are essential to optimize therapeutic strategies and translate them into clinical and industrial applications, ultimately addressing the global challenges posed by biofilm and antimicrobial resistance.
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Affiliation(s)
- Ambreen Kauser
- Department of Biotechnology, Latvian Institute of Organic Synthesis, Aizkraukles 21, LV-1006 Riga, Latvia; (A.K.); (E.P.)
- Faculty of Materials Science and Applied Chemistry, Riga Technical University, Paula Valdena 3, LV-1048 Riga, Latvia
| | - Emilio Parisini
- Department of Biotechnology, Latvian Institute of Organic Synthesis, Aizkraukles 21, LV-1006 Riga, Latvia; (A.K.); (E.P.)
- Department of Chemistry “G. Ciamician”, University of Bologna, Via Selmi 2, 40126 Bologna, Italy
| | - Giulia Suarato
- Istituto di Elettronica e di Ingegneria dell’Informazione e delle Telecomunicazioni, Consiglio Nazionale delle Ricerche, CNR-IEIIT, Piazza Leonardo da Vinci 32, 20133 Milano, Italy
| | - Rossella Castagna
- Department of Biotechnology, Latvian Institute of Organic Synthesis, Aizkraukles 21, LV-1006 Riga, Latvia; (A.K.); (E.P.)
- Dipartimento di Chimica, Materiali e Ingegneria Chimica “G. Natta”, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133 Milano, Italy
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6
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López-Corrales M, Rovira A, Gandioso A, Nonell S, Bosch M, Marchán V. Mitochondria-Targeted COUPY Photocages: Synthesis and Visible-Light Photoactivation in Living Cells. J Org Chem 2023. [PMID: 37209100 DOI: 10.1021/acs.joc.3c00387] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Releasing bioactive molecules in specific subcellular locations from the corresponding caged precursors offers great potential in photopharmacology, especially when using biologically compatible visible light. By taking advantage of the intrinsic preference of COUPY coumarins for mitochondria and their long wavelength absorption in the visible region, we have synthesized and fully characterized a series of COUPY-caged model compounds to investigate how the structure of the coumarin caging group affects the rate and efficiency of the photolysis process. Uncaging studies using yellow (560 nm) and red light (620 nm) in phosphate-buffered saline medium have demonstrated that the incorporation of a methyl group in a position adjacent to the photocleavable bond is particularly important to fine-tune the photochemical properties of the caging group. Additionally, the use of a COUPY-caged version of the protonophore 2,4-dinitrophenol allowed us to confirm by confocal microscopy that photoactivation can occur within mitochondria of living HeLa cells upon irradiation with low doses of yellow light. The new photolabile protecting groups presented here complement the photochemical toolbox in therapeutic applications since they will facilitate the delivery of photocages of biologically active compounds into mitochondria.
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Affiliation(s)
- Marta López-Corrales
- Departament de Química Inorgànica i Orgànica, Secció de Química Orgànica, Institut de Biomedicina de la Universitat de Barcelona (IBUB), Universitat de Barcelona (UB), Martí i Franqués 1-11, E-08028 Barcelona, Spain
| | - Anna Rovira
- Departament de Química Inorgànica i Orgànica, Secció de Química Orgànica, Institut de Biomedicina de la Universitat de Barcelona (IBUB), Universitat de Barcelona (UB), Martí i Franqués 1-11, E-08028 Barcelona, Spain
| | - Albert Gandioso
- Departament de Química Inorgànica i Orgànica, Secció de Química Orgànica, Institut de Biomedicina de la Universitat de Barcelona (IBUB), Universitat de Barcelona (UB), Martí i Franqués 1-11, E-08028 Barcelona, Spain
| | - Santi Nonell
- Institut Químic de Sarrià, Universitat Ramon Llull, Vía Augusta 390, E-08017 Barcelona, Spain
| | - Manel Bosch
- Unitat de Microscòpia Òptica Avançada, Centres Científics i Tecnològics (CCiTUB), Universitat de Barcelona (UB), Av. Diagonal 643, E-08028 Barcelona, Spain
| | - Vicente Marchán
- Departament de Química Inorgànica i Orgànica, Secció de Química Orgànica, Institut de Biomedicina de la Universitat de Barcelona (IBUB), Universitat de Barcelona (UB), Martí i Franqués 1-11, E-08028 Barcelona, Spain
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7
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Velema WA. Exploring antibiotic resistance with chemical tools. Chem Commun (Camb) 2023; 59:6148-6158. [PMID: 37039397 PMCID: PMC10194278 DOI: 10.1039/d3cc00759f] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2023] [Accepted: 04/05/2023] [Indexed: 04/08/2023]
Abstract
Antibiotic resistance is an enormous problem that is accountable for over a million deaths annually, with numbers expected to significantly increase over the coming decades. Although some of the underlying causes leading up to antibiotic resistance are well understood, many of the molecular processes involved remain elusive. To better appreciate at a molecular level how resistance emerges, customized chemical biology tools can offer a solution. This Feature Article attempts to provide an overview of the wide variety of tools that have been developed over the last decade, by highlighting some of the more illustrative examples. These include the use of fluorescent, photoaffinity and activatable antibiotics and bacterial components to start to unravel the molecular mechanisms involved in resistance. The antibiotic crisis is an eminent global threat and requires the continuous development of creative chemical tools to dissect and ultimately counteract resistance.
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Affiliation(s)
- Willem A Velema
- Institute for Molecules and Materials, Radboud University Nijmegen, The Netherlands, Heyendaalseweg 135, 6525 AJ, Nijmegen, The Netherlands.
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8
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Stimuli-Responsive Boron-Based Materials in Drug Delivery. Int J Mol Sci 2023; 24:ijms24032757. [PMID: 36769081 PMCID: PMC9917063 DOI: 10.3390/ijms24032757] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2022] [Revised: 01/26/2023] [Accepted: 01/28/2023] [Indexed: 02/04/2023] Open
Abstract
Drug delivery systems, which use components at the nanoscale level as diagnostic tools or to release therapeutic drugs to particular target areas in a regulated manner, are a fast-evolving field of science. The active pharmaceutical substance can be released via the drug delivery system to produce the desired therapeutic effect. The poor bioavailability and irregular plasma drug levels of conventional drug delivery systems (tablets, capsules, syrups, etc.) prevent them from achieving sustained delivery. The entire therapy process may be ineffective without a reliable delivery system. To achieve optimal safety and effectiveness, the drug must also be administered at a precision-controlled rate and the targeted spot. The issues with traditional drug delivery are overcome by the development of stimuli-responsive controlled drug release. Over the past decades, regulated drug delivery has evolved considerably, progressing from large- and nanoscale to smart-controlled drug delivery for several diseases. The current review provides an updated overview of recent developments in the field of stimuli-responsive boron-based materials in drug delivery for various diseases. Boron-containing compounds such as boron nitride, boronic acid, and boron dipyrromethene have been developed as a moving field of research in drug delivery. Due to their ability to achieve precise control over drug release through the response to particular stimuli (pH, light, glutathione, glucose or temperature), stimuli-responsive nanoscale drug delivery systems are attracting a lot of attention. The potential of developing their capabilities to a wide range of nanoscale systems, such as nanoparticles, nanosheets/nanospheres, nanotubes, nanocarriers, microneedles, nanocapsules, hydrogel, nanoassembly, etc., is also addressed and examined. This review also provides overall design principles to include stimuli-responsive boron nanomaterial-based drug delivery systems, which might inspire new concepts and applications.
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9
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Telegin FY, Karpova VS, Makshanova AO, Astrakhantsev RG, Marfin YS. Solvatochromic Sensitivity of BODIPY Probes: A New Tool for Selecting Fluorophores and Polarity Mapping. Int J Mol Sci 2023; 24:1217. [PMID: 36674731 PMCID: PMC9860957 DOI: 10.3390/ijms24021217] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2022] [Revised: 12/21/2022] [Accepted: 12/28/2022] [Indexed: 01/11/2023] Open
Abstract
This research work is devoted to collecting a high-quality dataset of BODIPYs in a series of 10-30 solvents. In total, 115 individual compounds in 71 solvents are represented by 1698 arrays of the spectral and photophysical properties of the fluorophore. Each dye for a series of solvents is characterized by a calculated value of solvatochromic sensitivity according to a semiempirical approach applied to a series of solvents. The whole dataset is classified into 6 and 24 clusters of solvatochromic sensitivity, from high negative to high positive solvatochromism. The results of the analysis are visualized by the polarity mapping plots depicting, in terms of wavenumbers, the absorption versus emission, stokes shift versus - (absorption maxima + emission maxima), and quantum yield versus stokes shift. An analysis of the clusters combining several dyes in an individual series of solvents shows that dyes of a high solvatochromic sensitivity demonstrate regular behaviour of the corresponding plots suitable for polarity and viscosity mapping. The fluorophores collected in this study represent a high quality dataset of pattern dyes for analytical and bioanalytical applications. The developed tools could be applied for the analysis of the applicability domain of the fluorescent sensors.
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Affiliation(s)
- Felix Y. Telegin
- G.A. Krestov Institute of Solution Chemistry of the RAS, 153045 Ivanovo, Russia
| | - Viktoria S. Karpova
- Department of Inorganic Chemistry, Ivanovo State University of Chemistry and Technology, 153000 Ivanovo, Russia
| | - Anna O. Makshanova
- Department of Natural Sciences, Mendeleev University of Chemical Technology of Russia, 125047 Moscow, Russia
| | - Roman G. Astrakhantsev
- HSE Tikhonov Moscow Institute of Electronics and Mathematics, HSE University, 101000 Moscow, Russia
| | - Yuriy S. Marfin
- G.A. Krestov Institute of Solution Chemistry of the RAS, 153045 Ivanovo, Russia
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10
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Schulte AM, Alachouzos G, Szymański W, Feringa BL. Strategy for Engineering High Photolysis Efficiency of Photocleavable Protecting Groups through Cation Stabilization. J Am Chem Soc 2022; 144:12421-12430. [PMID: 35775744 PMCID: PMC9284546 DOI: 10.1021/jacs.2c04262] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
![]()
Photolabile protecting
groups (PPGs) enable the precise activation
of molecular function with light in many research areas, such as photopharmacology,
where remote spatiotemporal control over the release of a molecule
is needed. The design and application of PPGs in recent years have
particularly focused on the development of molecules with high molar
absorptivity at long irradiation wavelengths. However, a crucial parameter,
which is pivotal to the efficiency of uncaging and which has until
now proven highly challenging to improve, is the photolysis quantum
yield (QY). Here, we describe a novel and general approach to greatly
increase the photolysis QY of heterolytic PPGs through stabilization
of an intermediate chromophore cation. When applied to coumarin PPGs,
our strategy resulted in systems possessing an up to a 35-fold increase
in QY and a convenient fluorescent readout during their uncaging,
all while requiring the same number of synthetic steps for their preparation
as the usual coumarin systems. We demonstrate that the same QY engineering
strategy applies to different photolysis payloads and even different
classes of PPGs. Furthermore, analysis of the DFT-calculated energy
barriers in the first singlet excited state reveals valuable insights
into the important factors that determine photolysis efficiency. The
strategy reported herein will enable the development of efficient
PPGs tailored for many applications.
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Affiliation(s)
- Albert M Schulte
- Centre for Systems Chemistry, Stratingh Institute for Chemistry, Faculty for Science and Engineering, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands
| | - Georgios Alachouzos
- Centre for Systems Chemistry, Stratingh Institute for Chemistry, Faculty for Science and Engineering, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands
| | - Wiktor Szymański
- Centre for Systems Chemistry, Stratingh Institute for Chemistry, Faculty for Science and Engineering, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands.,Department of Radiology, Medical Imaging Center, University Medical Center Groningen, University of Groningen, Hanzeplein 1, 9713 GZ Groningen, The Netherlands
| | - Ben L Feringa
- Centre for Systems Chemistry, Stratingh Institute for Chemistry, Faculty for Science and Engineering, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands
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