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Aebisher D, Serafin I, Batóg-Szczęch K, Dynarowicz K, Chodurek E, Kawczyk-Krupka A, Bartusik-Aebisher D. Photodynamic Therapy in the Treatment of Cancer-The Selection of Synthetic Photosensitizers. Pharmaceuticals (Basel) 2024; 17:932. [PMID: 39065781 PMCID: PMC11279632 DOI: 10.3390/ph17070932] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2024] [Revised: 07/01/2024] [Accepted: 07/07/2024] [Indexed: 07/28/2024] Open
Abstract
Photodynamic therapy (PDT) is a promising cancer treatment method that uses photosensitizing (PS) compounds to selectively destroy tumor cells using laser light. This review discusses the main advantages of PDT, such as its low invasiveness, minimal systemic toxicity and low risk of complications. Special attention is paid to photosensitizers obtained by chemical synthesis. Three generations of photosensitizers are presented, starting with the first, based on porphyrins, through the second generation, including modified porphyrins, chlorins, 5-aminolevulinic acid (ALA) and its derivative hexyl aminolevulinate (HAL), to the third generation, which is based on the use of nanotechnology to increase the selectivity of therapy. In addition, current research trends are highlighted, including the search for new photosensitizers that can overcome the limitations of existing therapies, such as heavy-atom-free nonporphyrinoid photosensitizers, antibody-drug conjugates (ADCs) or photosensitizers with a near-infrared (NIR) absorption peak. Finally, the prospects for the development of PDTs are presented, taking into account advances in nanotechnology and biomedical engineering. The references include both older and newer works. In many cases, when writing about a given group of first- or second-generation photosensitizers, older publications are used because the properties of the compounds described therein have not changed over the years. Moreover, older articles provide information that serves as an introduction to a given group of drugs.
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Affiliation(s)
- David Aebisher
- Department of Photomedicine and Physical Chemistry, Medical College of the University of Rzeszów, 35-959 Rzeszów, Poland
| | - Iga Serafin
- Students English Division Science Club, Medical College of the University of Rzeszów, 35-959 Rzeszów, Poland
| | | | - Klaudia Dynarowicz
- Center for Innovative Research in Medical and Natural Sciences, Medical College of the University of Rzeszów, 35-310 Rzeszów, Poland;
| | - Ewa Chodurek
- Department of Biopharmacy, Faculty of Pharmaceutical Sciences in Sosnowiec, Medical University of Silesia in Katowice, Jedności 8 Str., 41-200 Sosnowiec, Poland;
| | - Aleksandra Kawczyk-Krupka
- Center for Laser Diagnostics and Therapy, Department of Internal Medicine, Angiology and Physical Medicine, Medical University of Silesia in Katowice, Batorego 15 Street, 41-902 Bytom, Poland
| | - Dorota Bartusik-Aebisher
- Department of Biochemistry and General Chemistry, Medical College of the University of Rzeszów, 35-959 Rzeszów, Poland;
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Jena S, Mohanty P, Rout Rout S, Kumar Pati S, Biswal HS. Thio and Seleno-Psoralens as Efficient Triplet Harvesting Photosensitizers for Photodynamic Therapy. Chemistry 2024; 30:e202400733. [PMID: 38758636 DOI: 10.1002/chem.202400733] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2024] [Revised: 04/27/2024] [Accepted: 05/17/2024] [Indexed: 05/19/2024]
Abstract
The Psoralen (Pso) molecule finds extensive applications in photo-chemotherapy, courtesy of its triplet state forming ability. Sulfur and selenium replacement of exocyclic carbonyl oxygen of organic chromophores foster efficient triplet harvesting with near unity triplet quantum yield. These triplet-forming photosensitizers are useful in Photodynamic Therapy (PDT) applications for selective apoptosis of cancer cells. In this work, we have critically assessed the effect of the sulfur and selenium substitution at the exocyclic carbonyl (TPso and SePso, respectively) and endocyclic oxygen positions of Psoralen. It resulted in a significant redshifted absorption spectrum to access the PDT therapeutic window with increased oscillator strength. The reduction in singlet-triplet energy gap and enhancement in the spin-orbit coupling values increase the number of intersystem crossing (ISC) pathways to the triplet manifold, which shortens the ISC lifetime from 10-5 s for Pso to 10-8 s for TPso and 10-9 s for SePso. The intramolecular photo-induced electron transfer process, a competitive pathway to ISC, is also considerably curbed by exocyclic functionalizations. In addition, a maximum of 115 GM of two-photon absorption (2PA) with IR absorption (660-1050 nm) confirms that the Psoralen skeleton can be effectively tweaked via single chalcogen atom replacement to design a suitable PDT photosensitizer.
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Affiliation(s)
- Subhrakant Jena
- School of Chemical Sciences, National Institute of Science Education and Research (NISER), PO- Bhimpur-Padanpur Via-Jatni, District- Khurda, PIN - 752050, Bhubaneswar, India
- Homi Bhabha National Institute, Training School Complex, Anushakti Nagar, Mumbai 400094, India
| | - Pranay Mohanty
- School of Chemical Sciences, National Institute of Science Education and Research (NISER), PO- Bhimpur-Padanpur Via-Jatni, District- Khurda, PIN - 752050, Bhubaneswar, India
- Homi Bhabha National Institute, Training School Complex, Anushakti Nagar, Mumbai 400094, India
| | - Saiprakash Rout Rout
- School of Chemical Sciences, National Institute of Science Education and Research (NISER), PO- Bhimpur-Padanpur Via-Jatni, District- Khurda, PIN - 752050, Bhubaneswar, India
- Homi Bhabha National Institute, Training School Complex, Anushakti Nagar, Mumbai 400094, India
| | - Saswat Kumar Pati
- School of Chemical Sciences, National Institute of Science Education and Research (NISER), PO- Bhimpur-Padanpur Via-Jatni, District- Khurda, PIN - 752050, Bhubaneswar, India
- Homi Bhabha National Institute, Training School Complex, Anushakti Nagar, Mumbai 400094, India
| | - Himansu S Biswal
- School of Chemical Sciences, National Institute of Science Education and Research (NISER), PO- Bhimpur-Padanpur Via-Jatni, District- Khurda, PIN - 752050, Bhubaneswar, India
- Homi Bhabha National Institute, Training School Complex, Anushakti Nagar, Mumbai 400094, India
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Khatun MN, Nandy S, Roy H, Ghosh SS, Kumar S, Iyer PK. Sulphur-atom positional engineering in perylenimide: structure-property relationships and H-aggregation directed type-I photodynamic therapy. Chem Sci 2024; 15:9298-9317. [PMID: 38903228 PMCID: PMC11186329 DOI: 10.1039/d4sc01180e] [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: 02/19/2024] [Accepted: 05/10/2024] [Indexed: 06/22/2024] Open
Abstract
An innovative design strategy of placing sulfur (S)-atoms within the pendant functional groups and at carbonyl positions in conventional perylenimide (PNI-O) has been demonstrated to investigate the condensed state structure-property relationship and potential photodynamic therapy (PDT) application. Incorporation of simply S-atoms at the peri-functionalized perylenimide (RPNI-O) leads to an aggregation-induced enhanced emission luminogen (AIEEgen), 2-hexyl-8-(thianthren-1-yl)-1H-benzo[5,10]anthra[2,1,9-def]isoquinoline-1,3(2H)-dione (API), which achieves a remarkable photoluminescence quantum yield (Φ PL) of 0.85 in aqueous environments and established novel AIE mechanisms. Additionally, substitution of the S-atom at the carbonyl position in RPNI-O leads to thioperylenimides (RPNI-S): 2-hexyl-8-phenyl-1H-benzo[5,10]anthra[2,1,9-def]isoquinoline-1,3(2H)-dithione (PPIS), 8-([2,2'-bithiophen]-5-yl)-2-hexyl-1H-benzo[5,10]anthra[2,1,9-def]isoquinoline-1,3(2H)-dithione (THPIS), and 2-hexyl-8-(thianthren-1-yl)-1H-benzo[5,10]anthra[2,1,9-def]isoquinoline-1,3(2H)-dithion (APIS), with distinct photophysical properties (enlarged spin-orbit coupling (SOC) and Φ PL ≈ 0.00), and developed diverse potent photosensitizers (PSs). The present work provides a novel SOC enhancement mechanism via pronounced H-aggregation. Surprisingly, the lowest singlet oxygen quantum yield (Φ Δ) and theoretical calculation suggest the specific type-I PDT for RPNI-S. Interestingly, RPNI-S efficiently produces superoxide (O2˙-) due to its remarkably lower Gibbs free energy (ΔG) values (THPIS: -40.83 kcal mol-1). The non-toxic and heavy-atom free very specific thio-based PPIS and THPIS PSs showed selective and efficient PDT under normoxia, as a rare example.
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Affiliation(s)
- Mst Nasima Khatun
- Department of Chemistry, Indian Institute of Technology Guwahati Guwahati 781039 Assam India +91-3612582349
| | - Satyendu Nandy
- Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati Guwahati 781039 Assam India
| | - Hirakjyoti Roy
- Centre for Nanotechnology, Indian Institute of Technology Guwahati Guwahati 781039 Assam India
| | - Siddhartha Sankar Ghosh
- Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati Guwahati 781039 Assam India
- Centre for Nanotechnology, Indian Institute of Technology Guwahati Guwahati 781039 Assam India
| | - Sachin Kumar
- Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati Guwahati 781039 Assam India
| | - Parameswar Krishnan Iyer
- Department of Chemistry, Indian Institute of Technology Guwahati Guwahati 781039 Assam India +91-3612582349
- Centre for Nanotechnology, Indian Institute of Technology Guwahati Guwahati 781039 Assam India
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Polonius S, Lehrner D, González L, Mai S. Resolving Photoinduced Femtosecond Three-Dimensional Solute-Solvent Dynamics through Surface Hopping Simulations. J Chem Theory Comput 2024; 20:4738-4750. [PMID: 38768386 PMCID: PMC11171268 DOI: 10.1021/acs.jctc.4c00169] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2024] [Revised: 04/22/2024] [Accepted: 05/07/2024] [Indexed: 05/22/2024]
Abstract
Photoinduced dynamics in solution is governed by mutual solute-solvent interactions, which give rise to phenomena like solvatochromism, the Stokes shift, dual fluorescence, or charge transfer. Understanding these phenomena requires simulating the solute's photoinduced dynamics and simultaneously resolving the three-dimensional solvent distribution dynamics. If using trajectory surface hopping (TSH) to this aim, thousands of trajectories are required to adequately sample the time-dependent three-dimensional solvent distribution functions, and thus resolve the solvent dynamics with sub-Ångstrom and femtosecond accuracy and sufficiently low noise levels. Unfortunately, simulating thousands of trajectories with TSH in the framework of hybrid quantum mechanical/molecular mechanical (QM/MM) can be prohibitively expensive when employing ab initio electronic structure methods. To tackle this challenge, we recently introduced a computationally efficient approach that combines efficient linear vibronic coupling models with molecular mechanics (LVC/MM) via electrostatic embedding [Polonius et al., JCTC 2023, 19, 7171-7186]. This method provides solvent-embedded, nonadiabatically coupled potential energy surfaces while scaling similarly to MM force fields. Here, we employ TSH with LVC/MM to unravel the photoinduced dynamics of two small thiocarbonyl compounds solvated in water. We describe how to estimate the number of trajectories required to produce nearly noise-free three-dimensional solvent distribution functions and present an analysis based on approximately 10,000 trajectories propagated for 3 ps. In the electronic ground state, both molecules exhibit in-plane hydrogen bonds to the sulfur atom. Shortly after excitation, these bonds are broken and reform perpendicular to the molecular plane on timescales that differ by an order of magnitude due to steric effects. We also show that the solvent relaxation dynamics is coupled to the electronic dynamics, including intersystem crossing. These findings are relevant to advance the understanding of the coupled solute-solvent dynamics of solvated photoexcited molecules, e.g., biologically relevant thio-nucleobases.
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Affiliation(s)
- Severin Polonius
- Institute
of Theoretical Chemistry, Faculty of Chemistry, University of Vienna, Währinger Str. 17, 1090 Vienna, Austria
- Vienna
Doctoral School in Chemistry (DoSChem), University of Vienna, Währinger Str. 42, 1090 Vienna, Austria
| | - David Lehrner
- Institute
of Theoretical Chemistry, Faculty of Chemistry, University of Vienna, Währinger Str. 17, 1090 Vienna, Austria
| | - Leticia González
- Institute
of Theoretical Chemistry, Faculty of Chemistry, University of Vienna, Währinger Str. 17, 1090 Vienna, Austria
- Vienna
Research Platform on Accelerating Photoreaction Discovery, University of Vienna, Währinger Straße 17, 1090 Vienna, Austria
| | - Sebastian Mai
- Institute
of Theoretical Chemistry, Faculty of Chemistry, University of Vienna, Währinger Str. 17, 1090 Vienna, Austria
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Liu S, Lee Y, Chen L, Deng J, Ma T, Barbatti M, Bai S. Unexpected longer T 1 lifetime of 6-sulfur guanine than 6-selenium guanine: the solvent effect of hydrogen bonds to brake the triplet decay. Phys Chem Chem Phys 2024; 26:13965-13972. [PMID: 38669188 PMCID: PMC11078201 DOI: 10.1039/d4cp00875h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2024] [Accepted: 04/14/2024] [Indexed: 04/28/2024]
Abstract
The decay of the T1 state to the ground state is an essential property of photosensitizers because it decides the lifetime of excited states and, thus, the time window for sensitization. The sulfur/selenium substitution of carbonyl groups can red-shift absorption spectra and enhance the triplet yield because of the large spin-orbit coupling, modifying nucleobases to potential photosensitizers for various applications. However, replacing sulfur with selenium will also cause a much shorter T1 lifetime. Experimental studies found that the triplet decay rate of 6-seleno guanine (6SeGua) is 835 times faster than that of 6-thio guanine (6tGua) in aqueous solution. In this work, we reveal the mechanism of the T1 decay difference between 6SeGua and 6tGua by computing the activation energy and spin-orbit coupling for rate calculation. The solvent effect of water is treated with explicit microsolvation and implicit solvent models. We find that the hydrogen bond between the sulfur atom of 6tGua and the water molecule can brake the triplet decay, which is weaker in 6SeGua. This difference is crucial to explain the relatively long T1 lifetime of 6tGua in an aqueous solution. This insight emphasizes the role of solvents in modulating the excited state dynamics and the efficiency of photosensitizers, particularly in aqueous environments.
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Affiliation(s)
- Shaoting Liu
- School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou 510641, China.
- Beijing National Laboratory for Molecular Sciences, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China.
| | - Yuhsuan Lee
- Beijing National Laboratory for Molecular Sciences, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China.
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Lingfang Chen
- Beijing National Laboratory for Molecular Sciences, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China.
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jingheng Deng
- Beijing National Laboratory for Molecular Sciences, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China.
| | - Tongmei Ma
- School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou 510641, China.
| | - Mario Barbatti
- Aix Marseille University, CNRS, ICR, 13397 Marseille, France.
- Institut Universitaire de France, Paris 75231, France
| | - Shuming Bai
- Beijing National Laboratory for Molecular Sciences, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China.
- University of Chinese Academy of Sciences, Beijing 100049, China
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6
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Pal AK, Datta A. First-principles design of heavy-atom-free singlet oxygen photosensitizers for photodynamic therapy. J Chem Phys 2024; 160:164720. [PMID: 38682739 DOI: 10.1063/5.0196557] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2024] [Accepted: 04/10/2024] [Indexed: 05/01/2024] Open
Abstract
In photodynamic therapy (PDT) treatment, heavy-atom-free photosensitizers (PSs) are a great source of singlet oxygen photosensitizer. Reactive oxygen species (ROS) are produced by an energy transfer from the lowest energy triplet excited state to the molecular oxygen of cancer cells. To clarify the photophysical characteristics in the excited states of a few experimentally identified thionated (>C=S) molecules and their oxygenated congeners (>C=O), a quantum chemical study is conducted. This study illustrates the properties of the excited states in oxygen congeners that render them unsuitable for PDT treatment. Concurrently, a hierarchy is presented based on the utility of the lowest-energy triplet excitons of thionated compounds. Their non-radiative decay rates are calculated for reverse-ISC and inter-system crossover (ISC) processes. In addition, the vibronic importance of C=O and C=S bonds is clarified by the computation of the Huang-Rhys factor, effective vibrational mode, and reorganization energy inside the Marcus-Levich-Jörtner system. ROS generation in thionated PSs exceeds their oxygen congeners as kf ≪ kISC, where radiative decay rate is designated as kf. As a result, the current work offers a calculated strategy for analyzing the effectiveness of thionated photosensitizers in PDT.
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Affiliation(s)
- Arun K Pal
- School of Chemical Sciences, Indian Association for the Cultivation of Science, 2A and 2B Raja S. C. Mullick Road, Jadavpur, Kolkata 700 032, West Bengal, India
| | - Ayan Datta
- School of Chemical Sciences, Indian Association for the Cultivation of Science, 2A and 2B Raja S. C. Mullick Road, Jadavpur, Kolkata 700 032, West Bengal, India
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Baños J, Avilés A, Colmenares F. Disruptive Model That Explains for the Long-Lived Triplet States Observed for 2-Thiocytosine upon UVA Radiation. ACS OMEGA 2024; 9:13059-13066. [PMID: 38524487 PMCID: PMC10955585 DOI: 10.1021/acsomega.3c09471] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/28/2023] [Revised: 01/17/2024] [Accepted: 02/23/2024] [Indexed: 03/26/2024]
Abstract
The possible role of radical species in the formation of the long-lived triplet states observed for 2-thiocytosine upon UV irradiation was theoretically investigated. It is predicted that the radical fragments arising from the homolytic rupture of the NH group of the thiobase can be yielded upon ultraviolet-A radiation. Recombination of the radicals through the most favorable singlet channel yields the lowest-lying tautomer of the 2-thiocytosine (the amino-thiol form) through a barrierless pathway. The rebounding of the radical fragments along the triplet channels that emerge from the attack of the hydrogen to the nitrogen atoms next to the C-S bond leads to stable structures for the amino-thion-N1H and amino-thion-N3H tautomers. These results allow for the rationalization of the near-unity triplet yields observed when this pure light-atom organic molecule is exposed to UV irradiation, without invoking intersystem crossings between the electronic states of different spin-multiplicities. A similar study for cytosine showed that the energy required to induce the homolytic breaking of the N-H bond of the nucleobase is not attainable under UVA radiation. This result is consistent with the experimental fact that no triplet states are observed when this molecule is exposed to that light.
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Affiliation(s)
- Jorge Baños
- Departamento de Física y Química
Teórica, Facultad de Química, Universidad Nacional Autónoma de México, CDMX 04510, Mexico
| | | | - Fernando Colmenares
- Departamento de Física y Química
Teórica, Facultad de Química, Universidad Nacional Autónoma de México, CDMX 04510, Mexico
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Chang XP, Wang JL, Peng LY, Cen XJ, Yin BW, Xie BB. Mechanistic photophysics of tellurium-substituted cytosine: Electronic structure calculations and nonadiabatic dynamics simulations. Photochem Photobiol 2024; 100:339-354. [PMID: 37435854 DOI: 10.1111/php.13835] [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: 04/07/2023] [Revised: 06/24/2023] [Accepted: 06/26/2023] [Indexed: 07/13/2023]
Abstract
Previously, the MS-CASPT2 method was performed to study the static and qualitative photophysics of tellurium-substituted cytosine (TeC). To get quantitative information, we used our recently developed QTMF-FSSH dynamics method to simulate the excited-state decay of TeC. The CASSCF method was adopted to reduce the calculation costs, which was confirmed to provide reliable structures and energies as those of MS-CASPT2. A detailed structural analysis showed that only 5% trajectories will hop to the lower triplet or singlet state via the twisted (S2 /S1 /T2 )T intersection, while 67% trajectories will choose the planar intersections of (S2 /S1 /T3 /T2 /T1 )P and (S2 /S1 /T2 /T1 )P but subsequently become twisted in other electronic states. By contrast, ~28% trajectories will maintain in a plane throughout dynamics. Electronic population revealed that the S2 population will ultrafast transfer to the lower triplet or singlet state. Later, the TeC system will populate in the spin-mixed electronic states composed of S1 , T1 and T2 . At the end of 300 fs, most trajectories (~74%) will decay to the ground state and only 17.4% will survive in the triplet states. Our dynamics simulation verified that tellurium substitution will enhance the intersystem crossings, but the very short triplet lifetime (ca. 125 fs) will make TeC a less effective photosensitizer.
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Affiliation(s)
- Xue-Ping Chang
- Hangzhou Institute of Advanced Studies, Zhejiang Normal University, Hangzhou, China
- College of Chemistry and Chemical Engineering, Xinyang Normal University, Xinyang, China
| | - Jie-Lei Wang
- Hangzhou Institute of Advanced Studies, Zhejiang Normal University, Hangzhou, China
| | - Ling-Ya Peng
- Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education, College of Chemistry, Beijing Normal University, Beijing, China
| | - Xu-Jiang Cen
- Ningbo Zhongtian Engineering Co., Ltd., Ningbo, China
| | - Bo-Wen Yin
- Hangzhou Institute of Advanced Studies, Zhejiang Normal University, Hangzhou, China
| | - Bin-Bin Xie
- Hangzhou Institute of Advanced Studies, Zhejiang Normal University, Hangzhou, China
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Asplund M, Koga M, Wu YJ, Neumark DM. Time-resolved photoelectron spectroscopy of iodide-4-thiouracil cluster: The ππ* state as a doorway for electron attachment. J Chem Phys 2024; 160:054301. [PMID: 38299627 DOI: 10.1063/5.0187557] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2023] [Accepted: 01/09/2024] [Indexed: 02/02/2024] Open
Abstract
The photophysics of thiobases-nucleobases in which one or more oxygen atoms are replaced with sulfur atoms- vary greatly depending on the location of sulfonation. Not only are direct dynamics of a neutral thiobase impacted, but also the dynamics of excess electron accommodation. In this work, time-resolved photoelectron spectroscopy is used to measure binary anionic clusters of iodide and 4-thiouracil, I- · 4TU. We investigate charge transfer dynamics driven by excitation at 3.88 eV, corresponding to the lowest ππ* transition of the thiouracil, and at 4.16 eV, near the cluster vertical detachment energy. The photoexcited state dynamics are probed by photodetachment with 1.55 and 3.14 eV pulses. Excitation at 3.88 eV leads to a signal from a valence-bound ion only, indicating a charge accommodation mechanism that does not involve a dipole-bound anion as an intermediate. Excitation at 4.16 eV rapidly gives rise to dipole-bound and valence-bound ion signals, with a second rise in the valence-bound signal corresponding to the decay of the dipole-bound signal. The dynamics associated with the low energy ππ* excitation of 4-thiouracil provide a clear experimental proof for the importance of localized excitation and electron backfilling in halide-nucleobase clusters.
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Affiliation(s)
- Megan Asplund
- Department of Chemistry, University of California, Berkeley, California 94720, USA
| | - Masafumi Koga
- Department of Chemistry, University of California, Berkeley, California 94720, USA
| | - Ying Jung Wu
- Department of Chemistry, University of California, Berkeley, California 94720, USA
| | - Daniel M Neumark
- Department of Chemistry, University of California, Berkeley, California 94720, USA
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
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10
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Abdelgawwad AMA, Roca-Sanjuán D, Francés-Monerris A. Electronic spectroscopy of gemcitabine and derivatives for possible dual-action photodynamic therapy applications. J Chem Phys 2023; 159:224106. [PMID: 38078522 DOI: 10.1063/5.0170949] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2023] [Accepted: 11/12/2023] [Indexed: 12/18/2023] Open
Abstract
In this paper, we explore the molecular basis of combining photodynamic therapy (PDT), a light-triggered targeted anticancer therapy, with the traditional chemotherapeutic properties of the well-known cytotoxic agent gemcitabine. A photosensitizer prerequisite is significant absorption of biocompatible light in the visible/near IR range, ideally between 600 and 1000 nm. We use highly accurate multiconfigurational CASSCF/MS-CASPT2/MM and TD-DFT methodologies to determine the absorption properties of a series of gemcitabine derivatives with the goal of red-shifting the UV absorption band toward the visible region and facilitating triplet state population. The choice of the substitutions and, thus, the rational design is based on important biochemical criteria and on derivatives whose synthesis is reported in the literature. The modifications tackled in this paper consist of: (i) substitution of the oxygen atom at O2 position with heavier atoms (O → S and O → Se) to red shift the absorption band and increase the spin-orbit coupling, (ii) addition of a lipophilic chain at the N7 position to enhance transport into cancer cells and slow down gemcitabine metabolism, and (iii) attachment of aromatic systems at C5 position to enhance red shift further. Results indicate that the combination of these three chemical modifications markedly shifts the absorption spectrum toward the 500 nm region and beyond and drastically increases spin-orbit coupling values, two key PDT requirements. The obtained theoretical predictions encourage biological studies to further develop this anticancer approach.
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Affiliation(s)
| | - Daniel Roca-Sanjuán
- Institut de Ciència Molecular, Universitat de València, 46071 València, Spain
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11
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Sunny J, Sebastian E, Sujilkumar S, Würthner F, Engels B, Hariharan M. Unveiling the intersystem crossing dynamics in N-annulated perylene bisimides. Phys Chem Chem Phys 2023; 25:28428-28436. [PMID: 37843851 DOI: 10.1039/d3cp03888b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2023]
Abstract
The efficient population of the triplet excited states in heavy metal-free organic chromophores has been one of the long-standing research problems to molecular photochemists. The negligible spin-orbit coupling matrix elements in the purely organic chromophores and the large singlet-triplet energy gap (ΔES-T) pose a hurdle for ultrafast intersystem crossing (ISC). Herein we report the unprecedented population of triplet manifold in a series of nitrogen-annulated perylene bisimide chromophores (NPBI and Br-NPBI). NPBI is found to have a moderate fluorescence quantum yield (Φf = 68 ± 5%), whereas Br-NPBI showcased a low fluorescence quantum yield (Φf = 2.0 ± 0.6%) in toluene. The femtosecond transient absorption measurements of Br-NPBI revealed ultrafast ISC (kISC = 1.97 × 1010 s-1) from the initially populated singlet excited state to the long-lived triplet excited states. The triplet quantum yields (ΦT = 95.2 ± 4.6% for Br-NPBI, ΦT = 18.7 ± 2.3% for NPBI) calculated from nanosecond transient absorption spectroscopy measurements showed the enhancement in triplet population upon bromine substitution. The quantum chemical calculations revealed the explicit role of nitrogen annulation in tuning the excited state energy levels to favor the ISC. The near degeneracy between the singlet and triplet excited states observed in NPBI and Br-NPBI (ΔES-T = -0.01 eV for NPBI, ΔES-T = 0.03 eV for Br-NPBI) facilitates the spin flipping in the molecules. Nitrogen annulation emerges as a design strategy to open up the ISC pathway and the rate of which can be further enhanced by the substitution of a heavier element.
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Affiliation(s)
- Jeswin Sunny
- School of Chemistry, Indian Institute of Science Education and Research Thiruvananthapuram (IISER TVM), Vithura, Thiruvananthapuram, Kerala, 695551, India.
| | - Ebin Sebastian
- School of Chemistry, Indian Institute of Science Education and Research Thiruvananthapuram (IISER TVM), Vithura, Thiruvananthapuram, Kerala, 695551, India.
| | - Suvarna Sujilkumar
- School of Chemistry, Indian Institute of Science Education and Research Thiruvananthapuram (IISER TVM), Vithura, Thiruvananthapuram, Kerala, 695551, India.
| | - Frank Würthner
- Institut für Organische Chemie & Center for Nanosystems Chemistry, Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Bernd Engels
- Institut für Physikalische und Theoretische Chemie, Universität Würzburg, Emil-Fischer-Strasse 42, 97074 Würzburg, Germany
| | - Mahesh Hariharan
- School of Chemistry, Indian Institute of Science Education and Research Thiruvananthapuram (IISER TVM), Vithura, Thiruvananthapuram, Kerala, 695551, India.
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12
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Xie M, Ren SX, Hu D, Zhong JM, Luo J, Tan Y, Li YP, Si LP, Cao J. The impact of the chalcogen-substitution element and initial spectroscopic state on excited-state relaxation pathways in nucleobase photosensitizers: a combination of static and dynamic studies. Phys Chem Chem Phys 2023; 25:27756-27765. [PMID: 37814579 DOI: 10.1039/d3cp03730d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/11/2023]
Abstract
The substitution of oxygen with chalcogen in carbonyl group(s) of canonical nucleobases gives an impressive triplet generation, enabling their promising applications in medicine and other emerging techniques. The excited-state relaxation S2(ππ*) → S1(nπ*) → T1(ππ*) has been considered the preferred path for triplet generation in these nucleobase derivatives. Here, we demonstrate enhanced quantum efficiency of direct intersystem crossing from S2 to triplet manifold upon substitution with heavier chalcogen elements. The excited-state relaxation dynamics of sulfur/selenium substituted guanines in a vacuum is investigated using a combination of static quantum chemical calculations and on-the-fly excited-state molecular dynamics simulations. We find that in sulfur-substitution the S2 state predominantly decays to the S1 state, while upon selenium-substitution the S2 state deactivation leads to simultaneous population of the S1 and T2,3 states in the same time scale and multi-state quasi-degeneracy region S2/S1/T2,3. Interestingly, the ultrafast deactivation of the spectroscopic S3 state of both studied molecules to the S1 state occurs through a successive S3 → S2 → S1 path involving a multi-state quasi-degeneracy S3/S2/S1. The populated S1 and T2 states will cross the lowest triplet state, and the S1 → T intersystem crossing happens in a multi-state quasi-degeneracy region S1/T2,3/T1 and is accelerated by selenium-substitution. The present study reveals the influence of both the chalcogen substitution element and initial spectroscopic state on the excited-state relaxation mechanism of nucleobase photosensitizers and also highlights the important role of multi-state quasi-degeneracy in mediating the complex relaxation process. These theoretical results provide additional insights into the intrinsic photophysics of nucleobase-based photosensitizers and are helpful for designing novel photo-sensitizers for real applications.
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Affiliation(s)
- Min Xie
- School of Materials Science and Hydrogen Energy & Guangdong Key Laboratory for Hydrogen Energy Technologies, Foshan University, Foshan, Guangdong, 528000, P. R. China
| | - Shuang-Xiao Ren
- School of Materials Science and Hydrogen Energy & Guangdong Key Laboratory for Hydrogen Energy Technologies, Foshan University, Foshan, Guangdong, 528000, P. R. China
| | - Die Hu
- School of Materials Science and Hydrogen Energy & Guangdong Key Laboratory for Hydrogen Energy Technologies, Foshan University, Foshan, Guangdong, 528000, P. R. China
| | - Ji-Meng Zhong
- School of Materials Science and Hydrogen Energy & Guangdong Key Laboratory for Hydrogen Energy Technologies, Foshan University, Foshan, Guangdong, 528000, P. R. China
| | - Jie Luo
- School of Materials Science and Hydrogen Energy & Guangdong Key Laboratory for Hydrogen Energy Technologies, Foshan University, Foshan, Guangdong, 528000, P. R. China
| | - Yin Tan
- School of Materials Science and Hydrogen Energy & Guangdong Key Laboratory for Hydrogen Energy Technologies, Foshan University, Foshan, Guangdong, 528000, P. R. China
| | - Yan-Ping Li
- School of Medicine, Foshan University, Foshan, Guangdong, 528000, P. R. China
| | - Li-Ping Si
- School of Materials Science and Hydrogen Energy & Guangdong Key Laboratory for Hydrogen Energy Technologies, Foshan University, Foshan, Guangdong, 528000, P. R. China
| | - Jun Cao
- School of Materials Science and Hydrogen Energy & Guangdong Key Laboratory for Hydrogen Energy Technologies, Foshan University, Foshan, Guangdong, 528000, P. R. China
- Guizhou Provincial Key Laboratory of Computational Nano-Material Science, Guizhou Education University, Guiyang, Guizhou, 550018, P. R. China.
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13
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Russel NS, Kodali G, Stanley RJ, Narayanan M. Screening for Novel Fluorescent Nucleobase Analogues Using Computational and Experimental Methods: 2-Amino-6-chloro-8-vinylpurine (2A6Cl8VP) as a Case Study. J Phys Chem B 2023; 127:7858-7871. [PMID: 37698525 DOI: 10.1021/acs.jpcb.3c03618] [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: 09/13/2023]
Abstract
Novel fluorescent nucleic acid base analogues (FBAs) with improved optical properties are needed in a variety of biological applications. 2-Amino-6-chloro-8-vinylpurine (2A6Cl8VP) is structural analogue of two existing highly fluorescent FBAs, 2-aminopurine (2AP) and 8-vinyladenine (8VA), and can therefore be expected to have similar base pairing as well as better optical properties compared to its counterparts. In order to determine the absorption and fluorescence properties of 2A6Cl8VP, as a first step, we used TD-DFT calculations and the polarizable continuum model for simulating the solvents and computationally predicted absorption and fluorescence maxima. To test the computational predictions, we also synthesized 2A6Cl8VP and measured its UV/vis absorbance, fluorescence emission, and fluorescence lifetime. The computationally predicted absorbance and fluorescence maxima of 2A6Cl8VP are in reasonable agreement to the experimental values and are significantly redshifted compared to 2AP and 8VA, allowing for its specific excitation. The fluorescence quantum yield of 2A6Cl8VP, however, is significantly lower than those of 2AP and 8VA. Overall, 2A6Cl8VP is a novel fluorescent nucleobase analogue, which can be useful in studying structural, biophysical, and biochemical applications.
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Affiliation(s)
- Nadim Shahriar Russel
- Department of Chemistry, Temple University, 1901 N. Broad Street, Philadelphia, Pennsylvania 19122, United States
| | - Goutham Kodali
- GlowDNA LLC., Malvern, Pennsylvania 19355, United States
| | - Robert J Stanley
- Department of Chemistry, Temple University, 1901 N. Broad Street, Philadelphia, Pennsylvania 19122, United States
| | - Madhavan Narayanan
- Department of Physical Sciences, Benedictine University, 5700 College Rd, Lisle, Illinois 60532, United States
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14
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Ortiz-Rodríguez LA, Fang YG, Niogret G, Hadidi K, Hoehn SJ, Folkwein HJ, Jockusch S, Tor Y, Cui G, Levi L, Crespo-Hernández CE. Thieno[3,4- d]pyrimidin-4(3 H)-thione: an effective, oxygenation independent, heavy-atom-free photosensitizer for cancer cells. Chem Sci 2023; 14:8831-8841. [PMID: 37621444 PMCID: PMC10445467 DOI: 10.1039/d3sc02592f] [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: 05/23/2023] [Accepted: 07/24/2023] [Indexed: 08/26/2023] Open
Abstract
All-organic, heavy-atom-free photosensitizers based on thionation of nucleobases are receiving increased attention because they are easy to make, noncytotoxic, work both in the presence and absence of molecular oxygen, and can be readily incorporated into DNA and RNA. In this contribution, the DNA and RNA fluorescent probe, thieno[3,4-d]pyrimidin-4(1H)-one, has been thionated to develop thieno[3,4-d]pyrimidin-4(3H)-thione, which is nonfluorescent and absorbs near-visible radiation with about 60% higher efficiency. Steady-state absorption and emission spectra are combined with transient absorption spectroscopy and CASPT2 calculations to delineate the electronic relaxation mechanisms of both pyrimidine derivatives in aqueous and acetonitrile solutions. It is demonstrated that thieno[3,4-d]pyrimidin-4(3H)-thione efficiently populates the long-lived and reactive triplet state generating singlet oxygen with a quantum yield of about 80% independent of solvent. It is further shown that thieno[3,4-d]pyrimidin-4(3H)-thione exhibits high photodynamic efficacy against monolayer melanoma cells and cervical cancer cells both under normoxic and hypoxic conditions. Our combined spectroscopic, computational, and in vitro data demonstrate the excellent potential of thieno[3,4-d]pyrimidin-4(1H)-thione as a heavy-atom-free PDT agent and paves the way for further development of photosensitizers based on the thionation of thieno[3,4-d]pyrimidine derivatives. Collectively, the experimental and computational results demonstrate that thieno[3,4-d]pyrimidine-4(3H)-thione stands out as the most promising thiobase photosensitizer developed to this date.
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Affiliation(s)
| | - Ye-Guang Fang
- Key Lab of Theoretical and Computational Photochemistry, Ministry of Education, Chemistry College, Beijing Normal University Beijing 100875 China
| | - Germain Niogret
- Department of Chemistry and Biochemistry, University of California San Diego La Jolla CA 92093 USA
| | - Kaivin Hadidi
- Department of Chemistry and Biochemistry, University of California San Diego La Jolla CA 92093 USA
| | - Sean J Hoehn
- Department of Chemistry, Case Western Reserve University Cleveland OH 44106 USA
| | - Heather J Folkwein
- Department of Chemistry, Case Western Reserve University Cleveland OH 44106 USA
| | - Steffen Jockusch
- Center for Photochemical Sciences, Bowling Green State University Bowling Green Ohio 43403 USA
| | - Yitzhak Tor
- Department of Chemistry and Biochemistry, University of California San Diego La Jolla CA 92093 USA
| | - Ganglong Cui
- Key Lab of Theoretical and Computational Photochemistry, Ministry of Education, Chemistry College, Beijing Normal University Beijing 100875 China
| | - Liraz Levi
- Celloram Inc Cleveland OH 44106 USA
- Department of Pediatrics, Case Western Reserve University School of Medicine Cleveland Ohio 44106 USA
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15
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Rafiq S, Weingartz NP, Kromer S, Castellano FN, Chen LX. Spin-vibronic coherence drives singlet-triplet conversion. Nature 2023; 620:776-781. [PMID: 37468632 DOI: 10.1038/s41586-023-06233-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Accepted: 05/18/2023] [Indexed: 07/21/2023]
Abstract
Design-specific control over the transitions between excited electronic states with different spin multiplicities is of the utmost importance in molecular and materials chemistry1-3. Previous studies have indicated that the combination of spin-orbit and vibronic effects, collectively termed the spin-vibronic effect, can accelerate quantum-mechanically forbidden transitions at non-adiabatic crossings4,5. However, it has been difficult to identify precise experimental manifestations of the spin-vibronic mechanism. Here we present coherence spectroscopy experiments that reveal the interplay between the spin, electronic and vibrational degrees of freedom that drive efficient singlet-triplet conversion in four structurally related dinuclear Pt(II) metal-metal-to-ligand charge-transfer (MMLCT) complexes. Photoexcitation activates the formation of a Pt-Pt bond, launching a stretching vibrational wavepacket. The molecular-structure-dependent decoherence and recoherence dynamics of this wavepacket resolve the spin-vibronic mechanism. We find that vectorial motion along the Pt-Pt stretching coordinates tunes the singlet and intermediate-state energy gap irreversibly towards the conical intersection and subsequently drives formation of the lowest stable triplet state in a ratcheting fashion. This work demonstrates the viability of using vibronic coherences as probes6-9 to clarify the interplay among spin, electronic and nuclear dynamics in spin-conversion processes, and this could inspire new modular designs to tailor the properties of excited states.
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Affiliation(s)
- Shahnawaz Rafiq
- Department of Chemistry, Northwestern University, Evanston, IL, USA
| | - Nicholas P Weingartz
- Department of Chemistry, Northwestern University, Evanston, IL, USA
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, IL, USA
| | - Sarah Kromer
- Department of Chemistry, North Carolina State University, Raleigh, NC, USA
| | - Felix N Castellano
- Department of Chemistry, North Carolina State University, Raleigh, NC, USA.
| | - Lin X Chen
- Department of Chemistry, Northwestern University, Evanston, IL, USA.
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, IL, USA.
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16
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Banerjee T, Dan K, Pal AK, Bej R, Datta A, Ghosh S. Redox-Triggered Activation of Heavy-Atom-Free Photosensitizer and Implications in Targeted Photodynamic Therapy. ACS Macro Lett 2023:928-934. [PMID: 37378476 DOI: 10.1021/acsmacrolett.3c00249] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/29/2023]
Abstract
A strategy for a redox-activatable heavy-atom-free photosensitizer (PS) based on thiolated naphthalimide has been demonstrated. The PS exhibits excellent reactive oxygen species (ROS) generation in the monomeric state. However, when encapsulated in a disulfide containing bioreducible amphiphilic triblock copolymer aggregate (polymersome), the PS exhibits aggregation in the confined hydrophobic environment, which results in a smaller exciton exchange rate between the singlet and triplet excited states (TDDFT studies), and consequently, the ROS generation ability of the PS was almost fully diminished. Such a PS (in the dormant state)-loaded redox-responsive polymersome showed excellent cellular uptake and intracellular release of the PS in its active form, which enabled cell killing upon light irradiation due to ROS generation. In a control experiment involving aggregates of a similar block copolymer, but lacking the bioreducible disulfide linkage, no intracellular reactivation of the PS was noticed, highlighting the importance of stimuli-responsive polymer assemblies in the area of targeted photodynamic therapy.
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Affiliation(s)
- Tanushri Banerjee
- School of Applied and Interdisciplinary Sciences, Indian Association for the Cultivation of Science, 2A and 2B Raja S. C. Mullick Road, Kolkata, India-700032
| | - Krishna Dan
- School of Applied and Interdisciplinary Sciences, Indian Association for the Cultivation of Science, 2A and 2B Raja S. C. Mullick Road, Kolkata, India-700032
| | - Arun K Pal
- School of Chemical Sciences, Indian Association for the Cultivation of Science, 2A and 2B Raja S. C. Mullick Road, Kolkata, India-700032
| | - Raju Bej
- School of Applied and Interdisciplinary Sciences, Indian Association for the Cultivation of Science, 2A and 2B Raja S. C. Mullick Road, Kolkata, India-700032
| | - Ayan Datta
- School of Chemical Sciences, Indian Association for the Cultivation of Science, 2A and 2B Raja S. C. Mullick Road, Kolkata, India-700032
| | - Suhrit Ghosh
- School of Applied and Interdisciplinary Sciences, Indian Association for the Cultivation of Science, 2A and 2B Raja S. C. Mullick Road, Kolkata, India-700032
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17
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Shu Y, Zhang L, Wu D, Chen X, Sun S, Truhlar DG. New Gradient Correction Scheme for Electronically Nonadiabatic Dynamics Involving Multiple Spin States. J Chem Theory Comput 2023; 19:2419-2429. [PMID: 37079755 DOI: 10.1021/acs.jctc.2c01173] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/22/2023]
Abstract
It has been recommended that the best representation to use for trajectory surface hopping (TSH) calculations is the fully adiabatic basis in which the Hamiltonian is diagonal. Simulations of intersystem crossing processes with conventional TSH methods require an explicit computation of nonadiabatic coupling vectors (NACs) in the molecular-Coulomb-Hamiltonian (MCH) basis, also called the spin-orbit-free basis, in order to compute the gradient in the fully adiabatic basis (also called the diagonal representation). This explicit requirement destroys some of the advantages of the overlap-based algorithms and curvature-driven algorithms that can be used for the most efficient TSH calculations. Therefore, although these algorithms allow one to perform NAC-free simulations for internal conversion processes, one still requires NACs for intersystem crossing. Here, we show that how the NAC requirement is circumvented by a new computation scheme called the time-derivative-matrix scheme.
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Affiliation(s)
- Yinan Shu
- Department of Chemistry and Supercomputing Institute, University of Minnesota, Minneapolis, Minnesota 55455-0431, United States
| | - Linyao Zhang
- School of Energy Science and Engineering, Harbin Institute of Technology, Harbin 150001, P. R. China
| | - Dihua Wu
- Department of Chemistry and Supercomputing Institute, University of Minnesota, Minneapolis, Minnesota 55455-0431, United States
| | - Xiye Chen
- School of Energy Science and Engineering, Harbin Institute of Technology, Harbin 150001, P. R. China
| | - Shaozeng Sun
- School of Energy Science and Engineering, Harbin Institute of Technology, Harbin 150001, P. R. China
| | - Donald G Truhlar
- Department of Chemistry and Supercomputing Institute, University of Minnesota, Minneapolis, Minnesota 55455-0431, United States
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18
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Ultrafast Photo-Ion Probing of the Relaxation Dynamics in 2-Thiouracil. Molecules 2023; 28:molecules28052354. [PMID: 36903604 PMCID: PMC10005304 DOI: 10.3390/molecules28052354] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2022] [Revised: 02/19/2023] [Accepted: 02/20/2023] [Indexed: 03/08/2023] Open
Abstract
In this work, we investigate the relaxation processes of 2-thiouracil after UV photoexcitation to the S2 state through the use of ultrafast, single-colour, pump-probe UV/UV spectroscopy. We place focus on investigating the appearance and subsequent decay signals of ionized fragments. We complement this with VUV-induced dissociative photoionisation studies collected at a synchrotron, allowing us to better understand and assign the ionisation channels involved in the appearance of the fragments. We find that all fragments appear when single photons with energy > 11 eV are used in the VUV experiments and hence appear through 3+ photon-order processes when 266 nm light is used. We also observe three major decays for the fragment ions: a sub-autocorrelation decay (i.e., sub-370 fs), a secondary ultrafast decay on the order of 300-400 fs, and a long decay on the order of 220 to 400 ps (all fragment dependent). These decays agree well with the previously established S2 → S1 → Triplet → Ground decay process. Results from the VUV study also suggest that some of the fragments may be created by dynamics occurring in the excited cationic state.
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19
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Yang P, Zhang Q, Zhang Y, Zhang H, Zhao J, Shi H, Liang L, Huang Y, Zheng Z, Yang H. Aggregation Triggers Red/Near-Infrared Light Hydrogen Production of Organic Dyes with High Efficiency. ACS Catal 2023. [DOI: 10.1021/acscatal.2c05962] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/06/2023]
Affiliation(s)
- Pengju Yang
- School of Chemistry and Chemical Engineering, Shanxi University, Taiyuan 030006, China
| | - Qi Zhang
- School of Chemistry and Chemical Engineering, Shanxi University, Taiyuan 030006, China
| | - Ya Zhang
- School of Chemistry and Chemical Engineering, Shanxi University, Taiyuan 030006, China
| | - Hongxia Zhang
- School of Chemistry and Chemical Engineering, Shanxi University, Taiyuan 030006, China
| | - Jianghong Zhao
- School of Chemistry and Chemical Engineering, Shanxi University, Taiyuan 030006, China
| | - Hu Shi
- School of Chemistry and Chemical Engineering, Shanxi University, Taiyuan 030006, China
- Institute of Molecular Science, Shanxi University, Taiyuan 030006, China
| | - Linfeng Liang
- School of Chemistry and Chemical Engineering, Shanxi University, Taiyuan 030006, China
| | - Yamin Huang
- State Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Microsystem and Information technology, Chinese Academy of Sciences, Shanghai 200050, China
| | - Zhanfeng Zheng
- State Key Laboratory of Coal Conversion, Institute of Coal Chemistry, Chinese Academy of Sciences, Taiyuan 030001, China
| | - Hengquan Yang
- School of Chemistry and Chemical Engineering, Shanxi University, Taiyuan 030006, China
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20
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Li Y, Lan Y, Zheng X, Zhao Y. Insights into Wavelength-Mediated Excited State Intramolecular Proton Transfer in Solution: UV Resonance Raman Spectroscopy and Theoretical Calculation. J Mol Liq 2023. [DOI: 10.1016/j.molliq.2023.121740] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/31/2023]
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21
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Boeije Y, Olivucci M. From a one-mode to a multi-mode understanding of conical intersection mediated ultrafast organic photochemical reactions. Chem Soc Rev 2023; 52:2643-2687. [PMID: 36970950 DOI: 10.1039/d2cs00719c] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/29/2023]
Abstract
This review discusses how ultrafast organic photochemical reactions are controlled by conical intersections, highlighting that decay to the ground-state at multiple points of the intersection space results in their multi-mode character.
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Affiliation(s)
- Yorrick Boeije
- Van 't Hoff Institute for Molecular Sciences (HIMS), University of Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands
| | - Massimo Olivucci
- Chemistry Department, University of Siena, Via Aldo Moro n. 2, 53100 Siena, Italy
- Chemistry Department, Bowling Green State University, Overman Hall, Bowling Green, Ohio 43403, USA
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22
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Kim H, Yang M, Kwon N, Cho M, Han J, Wang R, Qi S, Li H, Nguyen V, Li X, Cheng H, Yoon J. Recent progress on photodynamic therapy and photothermal therapy. B KOREAN CHEM SOC 2022. [DOI: 10.1002/bkcs.12655] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- Heejeong Kim
- Department of Chemistry and Nanoscience Ewha Womans University Seoul South Korea
| | - Mengyao Yang
- Department of Chemistry and Nanoscience Ewha Womans University Seoul South Korea
| | - Nahyun Kwon
- Department of Chemistry and Nanoscience Ewha Womans University Seoul South Korea
| | - Moonyeon Cho
- Department of Chemistry and Nanoscience Ewha Womans University Seoul South Korea
| | - Jingjing Han
- Department of Chemistry and Nanoscience Ewha Womans University Seoul South Korea
| | - Rui Wang
- Department of Chemistry and Nanoscience Ewha Womans University Seoul South Korea
| | - Sujie Qi
- Department of Chemistry and Nanoscience Ewha Womans University Seoul South Korea
| | - Haidong Li
- School of Bioengineering Dalian University of Technology Dalian China
| | - Van‐Nghia Nguyen
- Department of Chemistry and Nanoscience Ewha Womans University Seoul South Korea
| | - Xingshu Li
- College of Chemistry, State Key Laboratory of Photocatalysis for Energy and the Environment, Fujian Provincial Key Laboratory for Cancer Metastasis Chemoprevention and Chemotherapy Fuzhou University Fuzhou China
| | - Hong‐Bo Cheng
- State Key Laboratory of Organic−Inorganic Composites, Beijing Laboratory of Biomedical Materials, College of Materials Science and Engineering Beijing University of Chemical Technology Beijing P. R. China
| | - Juyoung Yoon
- Department of Chemistry and Nanoscience Ewha Womans University Seoul South Korea
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23
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Krancewicz K, Koput J, Hug GL, Marciniak B, Taras-Goslinska KM. Unusual photophysical properties of a new tricyclic derivative of thiopurines in terms of potential applications. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2022; 281:121620. [PMID: 35853257 DOI: 10.1016/j.saa.2022.121620] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2022] [Revised: 07/07/2022] [Accepted: 07/09/2022] [Indexed: 06/15/2023]
Abstract
The thio analogues of purine bases have been found to possess notable biological and pharmacological capabilities and have an important role to play as anticancer and immunosuppressive drugs. In this work a new tricyclic analogue of guanosine containing sulfur was synthesized, in particular, DTEG (2',3',5'-tri-O-acetyl-6,9-dithioethanoguanosine). Although there is promise for thiopurine derivatives for biomedical applications, there are some liabilities in regard to their exposure to light. As a preliminary survey for such difficulties with DTEG, this work looks into spectral and photophysical processes of DTEG using time-resolved and steady-state optical excitation. In contrast to other thiopurines, which have long-lived triplets, DTEG is shown to have a short-lived triplet making it less dangerous for singlet-oxygen sensitization. Even in anaerobic solutions, its photoreactivity is negligible. These various unusual photochemical properties of DTEG are consistent with DTEG being very promising as an alternative drug to the currently used 6-thiopurines. DTEG also has some interesting photophysical behavior that is distinct from other thioketones. Although thioketones have an unusual fluorescence violating Kasha's Rule and emitting from the second excited singlet state, DTEG does this also, but, in addition, it shows dual fluorescence by emitting from its first excited singlet as well. The assignments of the nature of these excited states are supported by DFT results. This theory and associated kinetic analysis show quantitatively that the dual fluorescence is, in part, tied to the relatively fast S2 to S1 internal conversion compared to other S2 decays and, in part, tied to the relatively slow nonradiative decay of S1 itself.
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Affiliation(s)
| | - Jacek Koput
- Faculty of Chemistry, Adam Mickiewicz University, 61-614 Poznan, Poland
| | - Gordon L Hug
- Radiation Laboratory, University of Notre Dame, Notre Dame 46556, USA
| | - Bronisław Marciniak
- Faculty of Chemistry, Adam Mickiewicz University, 61-614 Poznan, Poland; Centre for Advanced Technology, Adam Mickiewicz University, 61-614 Poznan, Poland
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24
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Ullrich S, Qu Y, Mohamadzade A, Shrestha S. The Effect of Methylation on the Triplet-State Dynamics of 2-Thiouracil: Time-Resolved Photoelectron Spectroscopy of 2-Thiothymine. J Phys Chem A 2022; 126:8211-8217. [DOI: 10.1021/acs.jpca.2c06051] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Susanne Ullrich
- Department of Physics and Astronomy, University of Georgia, Athens, Georgia 30602, United States
| | - Yingqi Qu
- Department of Physics and Astronomy, University of Georgia, Athens, Georgia 30602, United States
| | - Abed Mohamadzade
- Department of Physics and Astronomy, University of Georgia, Athens, Georgia 30602, United States
| | - Sarita Shrestha
- Department of Physics and Astronomy, University of Georgia, Athens, Georgia 30602, United States
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25
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Advancing biomedical applications via manipulating intersystem crossing. Coord Chem Rev 2022. [DOI: 10.1016/j.ccr.2022.214754] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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26
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Yao H, Liu S, Xing Z, Miao Y, Song Z, Li G, Huang J. Thionation toward High-Contrast ACQ-DIE Probes by Reprogramming the Aqueous Segregation Behavior: Enlightenment from a Sulfur-Substituted G-Quadruplex Ligand. Anal Chem 2022; 94:15231-15239. [DOI: 10.1021/acs.analchem.2c02388] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Haojun Yao
- State Key Laboratory of Chemo/Biosensing and Chemometrics, School of Biomedical Sciences, Hunan University, Changsha 410082, P. R. China
- College of Chemistry and Chemical Engineering, Hunan University, Changsha 410082, P. R. China
| | - Song Liu
- State Key Laboratory of Chemo/Biosensing and Chemometrics, School of Biomedical Sciences, Hunan University, Changsha 410082, P. R. China
| | - Zhiming Xing
- State Key Laboratory of Chemo/Biosensing and Chemometrics, School of Biomedical Sciences, Hunan University, Changsha 410082, P. R. China
| | - Yongxiang Miao
- College of Chemistry and Chemical Engineering, Jiangxi Normal University, Nanchang 330022, P. R. China
| | - Zhibin Song
- College of Chemistry and Chemical Engineering, Jiangxi Normal University, Nanchang 330022, P. R. China
| | - Guorui Li
- State Key Laboratory of Chemo/Biosensing and Chemometrics, School of Biomedical Sciences, Hunan University, Changsha 410082, P. R. China
| | - Jing Huang
- State Key Laboratory of Chemo/Biosensing and Chemometrics, School of Biomedical Sciences, Hunan University, Changsha 410082, P. R. China
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27
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Wu P, Wang X, Pan H, Chen J. Direct Observation of Excitation Wavelength-Dependent Ultrafast Intersystem Crossing in Cytosine Nucleoside Solution. J Phys Chem B 2022; 126:7975-7980. [PMID: 36179273 DOI: 10.1021/acs.jpcb.2c05865] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A triplet excited state can lead to different DNA photolesions, especially in cytosine and its nucleoside/nucleotide as they are hotspots for DNA mutations. However, the triplet state generation mechanism is in controversy, and experimental evidence of ultrafast intersystem crossing (ISC) has not been registered in these molecules. In this work, ultrafast ISC is directly observed in 2'-deoxycytidine (dCyd) solution by using femtosecond transient absorption spectroscopy. Surprisingly, we demonstrate that ISC in dCyd is sensitive to the excitation wavelength, and a spin-vibronic ISC mechanism is proposed. This finding is the last piece of the dCyd excited-state deactivation mechanism puzzle and sets the base for further investigation of triplet state-involved photophysics and photochemistry in dCyd-containing DNA.
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Affiliation(s)
- Peicong Wu
- State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200241, China
| | - Xueli Wang
- State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200241, China
| | - Haifeng Pan
- State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200241, China
| | - Jinquan Chen
- State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200241, China.,Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan, Shanxi 030006, China
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28
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Bertram L, Roberts SJ, Powner MW, Szabla R. Photochemistry of 2-thiooxazole: a plausible prebiotic precursor to RNA nucleotides. Phys Chem Chem Phys 2022; 24:21406-21416. [PMID: 36047336 PMCID: PMC7613695 DOI: 10.1039/d2cp03167a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Potentially prebiotic chemical reactions leading to RNA nucleotides involve periods of UV irradiation, which are necessary to promote selectivity and destroy biologially irrelevant side products. Nevertheless, UV light has only been applied to promote specific stages of prebiotic reactions and its effect on complete prebiotic reaction sequences has not been extensively studied. Here, we report on an experimental and computational investigation of the photostability of 2-thiooxazole (2-TO), a potential precursor of pyrimidine and 8-oxopurine nucleotides on early Earth. Our UV-irradiation experiments resulted in rapid decomposition of 2-TO into unidentified small molecule photoproducts. We further clarify the underlying photochemistry by means of accurate ab initio calculations and surface hopping molecular dynamics simulations. Overall, the computational results show efficient rupture of the aromatic ring upon the photoexcitation of 2-TO via breaking of the C-O bond. Consequently, the initial stage of the divergent prebiotic synthesis of pyrimidine and 8-oxopurine nucleotides would require periodic shielding from UV light either with sun screening chromophores or through a planetary scenario that would protect 2-TO until it is transformed into a more stable intermediate compound, e.g. oxazolidinone thione.
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Affiliation(s)
- Lauren Bertram
- EaStCHEM School of Chemistry, University of Edinburgh, Edinburgh, UK
| | - Samuel J Roberts
- Department of Chemistry, University College London, 20 Gordon Street, London, WC1H 0AJ, UK.,MRC Laboratory of Molecular Biology, Cambridge, UK
| | - Matthew W Powner
- Department of Chemistry, University College London, 20 Gordon Street, London, WC1H 0AJ, UK
| | - Rafał Szabla
- EaStCHEM School of Chemistry, University of Edinburgh, Edinburgh, UK.,Department of Physical and Quantum Chemistry, Faculty of Chemistry, Wrocław University of Science and Technology, 50-370 Wrocław, Poland.
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29
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Francés-Monerris A, Carmona-García J, Trabelsi T, Saiz-Lopez A, Lyons JR, Francisco JS, Roca-Sanjuán D. Photochemical and thermochemical pathways to S 2 and polysulfur formation in the atmosphere of Venus. Nat Commun 2022; 13:4425. [PMID: 35907911 PMCID: PMC9338966 DOI: 10.1038/s41467-022-32170-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2022] [Accepted: 07/18/2022] [Indexed: 11/25/2022] Open
Abstract
Polysulfur species have been proposed to be the unknown near-UV absorber in the atmosphere of Venus. Recent work argues that photolysis of one of the (SO)2 isomers, cis-OSSO, directly yields S2 with a branching ratio of about 10%. If correct, this pathway dominates polysulfur formation by several orders of magnitude, and by addition reactions yields significant quantities of S3, S4, and S8. We report here the results of high-level ab-initio quantum-chemistry computations that demonstrate that S2 is not a product in cis-OSSO photolysis. Instead, we establish a novel mechanism in which S2 is formed in a two-step process. Firstly, the intermediate S2O is produced by the coupling between the S and Cl atmospheric chemistries (in particular, SO reaction with ClS) and in a lesser extension by O-abstraction reactions from cis-OSSO. Secondly, S2O reacts with SO. This modified chemistry yields S2 and subsequent polysulfur abundances comparable to the photolytic cis-OSSO mechanism through a more plausible pathway. Ab initio quantification of the photodissociations at play fills a critical data void in current atmospheric models of Venus. Polysulfur compounds have been ascribed as the unknown near-UV absorbers in Venusian atmosphere and play a key role in the sulfur chemical cycle of this planet. Here, authors establish their production from (SO)2 on the grounds of quantifications of photochemical and thermal pathways involved in the sulfur chemical cycle of the planet.
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Affiliation(s)
| | - Javier Carmona-García
- Institut de Ciència Molecular, Universitat de València, 46071, València, Spain.,Department of Atmospheric Chemistry and Climate, Institute of Physical Chemistry Rocasolano, CSIC, 28006, Madrid, Spain
| | - Tarek Trabelsi
- Department of Earth and Environmental Sciences and Department of Chemistry, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Alfonso Saiz-Lopez
- Department of Atmospheric Chemistry and Climate, Institute of Physical Chemistry Rocasolano, CSIC, 28006, Madrid, Spain
| | | | - Joseph S Francisco
- Department of Earth and Environmental Sciences and Department of Chemistry, University of Pennsylvania, Philadelphia, PA, 19104, USA.
| | - Daniel Roca-Sanjuán
- Institut de Ciència Molecular, Universitat de València, 46071, València, Spain.
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30
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Valverde D, Mai S, Canuto S, Borin AC, González L. Ultrafast Intersystem Crossing Dynamics of 6-Selenoguanine in Water. JACS AU 2022; 2:1699-1711. [PMID: 35911449 PMCID: PMC9327080 DOI: 10.1021/jacsau.2c00250] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Rationalizing the photochemistry of nucleobases where an oxygen is replaced by a heavier atom is essential for applications that exploit near-unity triplet quantum yields. Herein, we report on the ultrafast excited-state deactivation mechanism of 6-selenoguanine (6SeGua) in water by combining nonadiabatic trajectory surface-hopping dynamics with an electrostatic embedding quantum mechanics/molecular mechanics (QM/MM) scheme. We find that the predominant relaxation mechanism after irradiation starts on the bright singlet S2 state that converts internally to the dark S1 state, from which the population is transferred to the triplet T2 state via intersystem crossing and finally to the lowest T1 state. This S2 → S1 → T2 → T1 deactivation pathway is similar to that observed for the lighter 6-thioguanine (6tGua) analogue, but counterintuitively, the T1 lifetime of the heavier 6SeGua is shorter than that of 6tGua. This fact is explained by the smaller activation barrier to reach the T1/S0 crossing point and the larger spin-orbit couplings of 6SeGua compared to 6tGua. From the dynamical simulations, we also calculate transient absorption spectra (TAS), which provide two time constants (τ1 = 131 fs and τ2 = 191 fs) that are in excellent agreement with the experimentally reported value (τexp = 130 ± 50 fs) (Farrel et al. J. Am. Chem. Soc. 2018, 140, 11214). Intersystem crossing itself is calculated to occur with a time scale of 452 ± 38 fs, highlighting that the TAS is the result of a complex average of signals coming from different nonradiative processes and not intersystem crossing alone.
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Affiliation(s)
- Danillo Valverde
- Department
of Fundamental Chemistry, Institute of Chemistry, University of São Paulo, Avenida Professor Lineu Prestes, 748, São Paulo, São Paulo CEP 05508-000, Brazil
- Institute
of Physics, University of São Paulo, Rua do Matão 1371, São Paulo, São Paulo CEP 05508-090, Brazil
| | - Sebastian Mai
- Institute
of Theoretical Chemistry, Faculty of Chemistry, University of Vienna, Währinger Straße 17, Vienna 1090, Austria
| | - Sylvio Canuto
- Institute
of Physics, University of São Paulo, Rua do Matão 1371, São Paulo, São Paulo CEP 05508-090, Brazil
| | - Antonio Carlos Borin
- Department
of Fundamental Chemistry, Institute of Chemistry, University of São Paulo, Avenida Professor Lineu Prestes, 748, São Paulo, São Paulo CEP 05508-000, Brazil
| | - Leticia González
- Institute
of Theoretical Chemistry, Faculty of Chemistry, University of Vienna, Währinger Straße 17, Vienna 1090, Austria
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31
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Jin P, Wang X, Pan H, Chen J. One order of magnitude increase of triplet state lifetime observed in deprotonated form selenium substituted uracil. Phys Chem Chem Phys 2022; 24:875-882. [PMID: 34908064 DOI: 10.1039/d1cp04811b] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Selenium nucleic acids possess unique properties and have been demonstrated to have a wide range of applications such as in DNA X-ray crystallography and novel medical therapies. However, as a heavy atom, selenium substitution may easily alter the photophysical properties of a nucleic acid by red-shifting the absorption spectra and introducing effective intersystem crossing to triplet excited states. In present work, the excited state dynamics of a naturally occurring selenium substituted uracil (2-selenuracil, 2SeU) is studied by using femtosecond transient absorption spectroscopy as well as quantum chemistry calculations. Ultrafast intersystem crossing to the lowest triplet state (T1) and effective non-radiative decay of this state to the ground state (S0) are demonstrated in the neutral form 2SeU. However, the triplet lifetime of the deprotonated form 2SeU is found to be almost one order of magnitude longer than that in the neutral one. Quantum chemistry calculations indicate that the short triplet lifetime in 2SeU is due to excited state population decay through a crossing point between T1 and S0. In the deprotonated form, shortening the N1-C2 bond length makes the structural distortion more difficult and brings a larger energy barrier on the pathway to the T1/S0 crossing point, resulting in one order of magnitude increase of the triplet state lifetime. Our study reveals one key factor to regulate the triplet lifetime of 2SeU and sets the stage to further investigate the photophysical and photochemical properties of 2SeU-containing DNA/RNA duplexes.
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Affiliation(s)
- Peipei Jin
- State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200241, China.
| | - Xueli Wang
- State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200241, China.
| | - Haifeng Pan
- State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200241, China.
| | - Jinquan Chen
- State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200241, China. .,Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan, Shanxi 030006, China
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32
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Teles-Ferreira DC, van Stokkum IH, Conti I, Ganzer L, Manzoni C, Garavelli M, Cerullo G, Nenov A, Borrego Varillas R, de Paula AM. Coherent vibrational modes promote the ultrafast internal conversion and intersystem crossing in thiobases. Phys Chem Chem Phys 2022; 24:21750-21758. [DOI: 10.1039/d2cp02073d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Thionated nucleobases are obtained by replacing oxygen with sulphur atoms in the canonical nucleobases. They absorb light efficiently in the near-ultraviolet, populating singlet states which undergo intersystem crossing to the...
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33
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Xie BB, Tang XF, Liu XY, Chang XP, Cui G. Mechanistic photophysics and photochemistry of unnatural bases and sunscreen molecules: insights from electronic structure calculations. Phys Chem Chem Phys 2021; 23:27124-27149. [PMID: 34849517 DOI: 10.1039/d1cp03994f] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Photophysics and photochemistry are basic subjects in the study of light-matter interactions and are ubiquitous in diverse fields such as biology, energy, materials, and environment. A full understanding of mechanistic photophysics and photochemistry underpins many recent advances and applications. This contribution first provides a short discussion on the theoretical calculation methods we have used in relevant studies, then we introduce our latest progress on the mechanistic photophysics and photochemistry of two classes of molecular systems, namely unnatural bases and sunscreens. For unnatural bases, we disclose the intrinsic driving forces for the ultrafast population to reactive triplet states, impacts of the position and degree of chalcogen substitutions, and the effects of complex environments. For sunscreen molecules, we reveal the photoprotection mechanisms that dissipate excess photon energy to the surroundings by ultrafast internal conversion to the ground state. Finally, relevant theoretical challenges and outlooks are discussed.
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Affiliation(s)
- Bin-Bin Xie
- Hangzhou Institute of Advanced Studies, Zhejiang Normal University, 1108 Gengwen Road, Hangzhou 311231, Zhejiang, P. R. China.
| | - Xiu-Fang Tang
- Hangzhou Institute of Advanced Studies, Zhejiang Normal University, 1108 Gengwen Road, Hangzhou 311231, Zhejiang, P. R. China.
| | - Xiang-Yang Liu
- College of Chemistry and Material Science, Sichuan Normal University, Chengdu, Sichuan, 610068, China
| | - Xue-Ping Chang
- College of Chemistry and Chemical Engineering, Xinyang Normal University, Xinyang 464000, P. R. China
| | - Ganglong Cui
- Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education College of Chemistry, Beijing Normal University, Beijing 100875, P. R. China.
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34
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Ortiz-Rodríguez LA, Hoehn SJ, Acquah C, Abbass N, Waidmann L, Crespo-Hernández CE. Femtosecond intersystem crossing to the reactive triplet state of the 2,6-dithiopurine skin cancer photosensitizer. Phys Chem Chem Phys 2021; 23:25048-25055. [PMID: 34730146 DOI: 10.1039/d1cp04415j] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Site-selected sulfur-substituted nucleobases are a class of all organic, heavy-atom-free photosensitizers for photodynamic therapy applications that exhibit excellent photophysical properties such as strong absorption in the ultraviolet-A region of the electromagnetic spectrum, near-unity triplet yields, and a high yield of singlet oxygen generation. Recent investigations on doubly thionated nucleobases, 2,4-dithiothymine, 2,4-dithiouracil, and 2,6-dithiopurine, demonstrated that these set of dithionated nucleobases outperform the photodynamic efficacy exhibit by 4-thiothymidine-the most widely studied singly substituted thiobase to date. Out of the three dithionated nucleobases, 2,6-dithiopurine was shown to be the most effective, exhibiting inhibition of cell proliferation of up to 63% when combined with a low UVA dose of 5 J cm-2. In this study, we elucidated the electronic relaxation pathways leading to the population of the reactive triplet state of 2,6-dithiopurine. 2,6-Dithiopurine populates the triplet manifold in less than 150 fs, reaching the nπ* triplet state minimum within a lifetime of 280 ± 50 fs. Subsequently, the population in the nπ* triplet state minimum internally converts to the long-lived ππ* triplet state within a lifetime of 3 ± 1 ps. The relatively slow internal conversion lifetime is associated with major conformational relaxation in going from the nπ* to ππ* triplet state minimum. A unity triplet yield of 1.0 ± 0.1 is measured.
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Affiliation(s)
| | - Sean J Hoehn
- Department of Chemistry, Case Western Reserve University, Cleveland, OH 44106, USA.
| | - Chris Acquah
- Department of Chemistry, Case Western Reserve University, Cleveland, OH 44106, USA.
| | - Nadia Abbass
- Department of Chemistry, Case Western Reserve University, Cleveland, OH 44106, USA.
| | - Lidia Waidmann
- Department of Chemistry, Case Western Reserve University, Cleveland, OH 44106, USA.
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35
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Pham TC, Nguyen VN, Choi Y, Lee S, Yoon J. Recent Strategies to Develop Innovative Photosensitizers for Enhanced Photodynamic Therapy. Chem Rev 2021; 121:13454-13619. [PMID: 34582186 DOI: 10.1021/acs.chemrev.1c00381] [Citation(s) in RCA: 556] [Impact Index Per Article: 185.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
This review presents a robust strategy to design photosensitizers (PSs) for various species. Photodynamic therapy (PDT) is a photochemical-based treatment approach that involves the use of light combined with a light-activated chemical, referred to as a PS. Attractively, PDT is one of the alternatives to conventional cancer treatment due to its noninvasive nature, high cure rates, and low side effects. PSs play an important factor in photoinduced reactive oxygen species (ROS) generation. Although the concept of photosensitizer-based photodynamic therapy has been widely adopted for clinical trials and bioimaging, until now, to our surprise, there has been no relevant review article on rational designs of organic PSs for PDT. Furthermore, most of published review articles in PDT focused on nanomaterials and nanotechnology based on traditional PSs. Therefore, this review aimed at reporting recent strategies to develop innovative organic photosensitizers for enhanced photodynamic therapy, with each example described in detail instead of providing only a general overview, as is typically done in previous reviews of PDT, to provide intuitive, vivid, and specific insights to the readers.
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Affiliation(s)
- Thanh Chung Pham
- Industry 4.0 Convergence Bionics Engineering, Pukyong National University, Busan 48513, Korea
| | - Van-Nghia Nguyen
- Department of Chemistry and Nanoscience, Ewha Womans University, Seoul 03760, Korea
| | - Yeonghwan Choi
- Industry 4.0 Convergence Bionics Engineering, Pukyong National University, Busan 48513, Korea
| | - Songyi Lee
- Department of Chemistry, Pukyong National University, Busan 48513, Korea.,Industry 4.0 Convergence Bionics Engineering, Pukyong National University, Busan 48513, Korea
| | - Juyoung Yoon
- Department of Chemistry and Nanoscience, Ewha Womans University, Seoul 03760, Korea
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36
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Solling TI. Nonstatistical Photoinduced Processes in Gaseous Organic Molecules. ACS OMEGA 2021; 6:29325-29344. [PMID: 34778606 PMCID: PMC8581993 DOI: 10.1021/acsomega.1c04035] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Indexed: 05/26/2023]
Abstract
Processes that proceed in femtoseconds are usually referred to as being ultrafast, and they are investigated in experiments that involve laser pulses with femtosecond duration in so-called pump probe schemes, where a light pulse triggers a molecular process and a second light pulse interrogates the temporal evolution of the molecular population. The focus of this review is on the reactivity patterns that arise when energy is not equally distributed on all the available degrees of freedom as a consequence of the very short time scale in play and on how the localization of internal energy in a specific mode can be thought of as directing a process toward (or away from) a certain outcome. The nonstatistical aspects are illustrated with examples from photophysics and photochemistry for a range of organic molecules. The processes are initiated by a variety of nuclear motions that are all governed by the energy gradients in the Franck-Condon region. Essentially, the molecules will start to adapt to the new electronic environment on the excited state to eventually reach the equilibrium structure. It is this structural change that is enabling an ultrafast electronic transition in cases where the nuclear motion leads to a transition point with significant coupling between to electronic states and to ultrafast reaction if there is a coupling to a reactive mode at the transition point between the involved states. With the knowledge of the relation between electronic excitation and equilibrium structure, it is possible to predict how the nuclei move after excitation and often whether an ultrafast (and inherently nonstatistical) electronic transition or even a bond breakage will take place. In addition to the understanding of how nonstatistical photoinduced processes proceed from a given excited state, it has been found that randomization of the energy does not even always take place when the molecule takes part in processes that are normally considered statistical, such as for example nonradiative transitions between excited states. This means that energy can be localized in a specific degree of freedom on a state other than the one that is initially prepared. This is a finding that could kickoff the ultimate dream in applied photochemistry; namely light excitation that leads to the rupture of a specific bond.
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Affiliation(s)
- Theis I. Solling
- Center for Integrative Petroleum
Research, King Fahd University of Petroleum
& Minerals, Dhahran, 31261, Saudi Arabia
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37
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Zhu YH, Tang XF, Chang XP, Zhang TS, Xie BB, Cui G. Mechanistic Photophysics of Tellurium-Substituted Uracils: Insights from Multistate Complete-Active-Space Second-Order Perturbation Calculations. J Phys Chem A 2021; 125:8816-8826. [PMID: 34606278 DOI: 10.1021/acs.jpca.1c06169] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The photophysical mechanisms of tellurium-substituted uracils were studied at the multistate complete-active-space second-order perturbation level with a particular focus on how the position and number of tellurium substitutions affect their nonadiabatic relaxation processes. Electronic structure analysis reveals that the lowest several excited states are closely concerned with the n and π orbitals at the Te7-C2 [Te8-C4] moiety of 2-tellurouracil (2TeU) [4TeU and 24TeU]. Both planar and twisted minima were optimized for 2TeU, whereas only planar ones were obtained for 4TeU and 24TeU, except for a twisted T1 minimum of 4TeU. Based on intersection structures and linearly interpolated internal coordinate paths, we proposed several feasible excited-state deactivation paths. It is found that the relaxation channels for 2TeU are more complicated than those of 4TeU and 24TeU. The electronic population transfer to the T1 state for 2TeU is easier than that for 4TeU and 24TeU in consideration of the barrier heights from the S2 Franck-Condon point to the S2/S1 or S2/T2 intersections. In addition, the recovery of the ground state from the T1 state for 2TeU will be more efficient than that for the other two systems as well.
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Affiliation(s)
- Yun-Hua Zhu
- Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education College of Chemistry, Beijing Normal University, Beijing 100875, P. R. China
| | - Xiu-Fang Tang
- Hangzhou Institute of Advanced Studies, Zhejiang Normal University, 1108 Gengwen Road, Hangzhou 311231, Zhejiang, P. R. China
| | - Xue-Ping Chang
- College of Chemistry and Chemical Engineering, Xinyang Normal University, Xinyang 464000, P. R. China
| | - Teng-Shuo Zhang
- College of Chemical Engineering, Zhejiang University of Technology, Hangzhou 310014, Zhejiang, P R. China
| | - Bin-Bin Xie
- Hangzhou Institute of Advanced Studies, Zhejiang Normal University, 1108 Gengwen Road, Hangzhou 311231, Zhejiang, P. R. China
| | - Ganglong Cui
- Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education College of Chemistry, Beijing Normal University, Beijing 100875, P. R. China
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38
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Nguyen VN, Heo S, Koh CW, Ha J, Kim G, Park S, Yoon J. A Simple Route toward Next-Generation Thiobase-Based Photosensitizers for Cancer Theranostics. ACS Sens 2021; 6:3462-3467. [PMID: 34432415 DOI: 10.1021/acssensors.1c01391] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Sulfur-substituted biocompatible carbonyl fluorophores have been recognized as effective heavy-atom-free photosensitizers (PSs) for cancer therapy due to their remarkable phototherapeutic properties. However, guidelines on their molecular design are still a substantial challenge. Most of the existing thiocarbonyl-based PSs are nonemissive in both the solution and restricted states, which hinders their further biomedical applications. Herein, we report the interesting finding that sulfur-substituted coumarins exhibit an uncommon phenomenon, aggregation-induced emission. More intriguingly, we also found that the introduction of a strong electron-accepting trifluoromethyl group is crucial to facilitate the mitochondrial-targeting ability of neutral coumarin fluorophores. The resulting CMS-2 PS displayed selective imaging of mitochondria and exhibited much higher photodynamic therapy efficiency toward cancer cells than that of the commercial PS erythrosine B. This work provides deep insight into the molecular design of heavy-atom-free thiobase-based PSs and simultaneously offers a great opportunity to develop novel mitochondrial-targeting fluorescent indicators with neutral bioinspired platforms.
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Affiliation(s)
- Van-Nghia Nguyen
- Department of Chemistry and Nanoscience, Ewha Womans University, Seoul 03760, Republic of Korea
| | - Seonye Heo
- Department of Chemistry and Nanoscience, Ewha Womans University, Seoul 03760, Republic of Korea
| | - Chang Woo Koh
- Department of Chemistry, Korea University, Seoul 02841, Republic of Korea
| | - Jeongsun Ha
- Department of Chemistry and Nanoscience, Ewha Womans University, Seoul 03760, Republic of Korea
| | - Gyoungmi Kim
- Department of Chemistry and Nanoscience, Ewha Womans University, Seoul 03760, Republic of Korea
| | - Sungnam Park
- Department of Chemistry, Korea University, Seoul 02841, Republic of Korea
| | - Juyoung Yoon
- Department of Chemistry and Nanoscience, Ewha Womans University, Seoul 03760, Republic of Korea
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39
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Ortiz-Rodríguez LA, Ortiz-Zayas G, Pollum M, Hoehn SJ, Jockusch S, Crespo-Hernández CE. Intramolecular Charge Transfer in the Azathioprine Prodrug Quenches Intersystem Crossing to the Reactive Triplet State in 6-Mercaptopurine †. Photochem Photobiol 2021; 98:617-632. [PMID: 34480764 DOI: 10.1111/php.13513] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Accepted: 08/30/2021] [Indexed: 11/26/2022]
Abstract
The thiopurine prodrugs 6-mercaptopurine and azathioprine are among the world's essential medications for acute lymphoblastic leukemia, immunosuppression and several autoimmune conditions. Thiopurine prodrugs are efficient UVA absorbers and singlet oxygen generators and the long-term treatment with these prodrugs correlates with a high incidence of sunlight-induced skin cancer in patients. In this contribution, we show that the electronic relaxation mechanisms and photochemical properties of azathioprine are remarkably different from those of 6-mercaptopurine upon absorption of UVA radiation. UVA excitation of 6-mercaptopurine results in nearly 100% triplet yield and up to 30% singlet oxygen generation, whereas excitation of azathioprine with UVA leads to triplet yields of 15-3% depending on pH of the aqueous solution and <1% singlet oxygen generation. While photoexcitation of 6-mercaptopurine and other thiopurine prodrugs can facilitate oxidatively generated cell damage, azathioprine's poor photosensitization ability reveals the use of interchromophoric charge-transfer interactions for the molecular design of photostable prodrugs exhibiting a remarkable reduction in photocytotoxic side effects before drug metabolization.
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Affiliation(s)
| | | | - Marvin Pollum
- Department of Chemistry, Case Western Reserve University, Cleveland, OH, USA
| | - Sean J Hoehn
- Department of Chemistry, Case Western Reserve University, Cleveland, OH, USA
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40
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Zobel JP, González L. The Quest to Simulate Excited-State Dynamics of Transition Metal Complexes. JACS AU 2021; 1:1116-1140. [PMID: 34467353 PMCID: PMC8397362 DOI: 10.1021/jacsau.1c00252] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Indexed: 05/15/2023]
Abstract
This Perspective describes current computational efforts in the field of simulating photodynamics of transition metal complexes. We present the typical workflows and feature the strengths and limitations of the different contemporary approaches. From electronic structure methods suitable to describe transition metal complexes to approaches able to simulate their nuclear dynamics under the effect of light, we give particular attention to build a bridge between theory and experiment by critically discussing the different models commonly adopted in the interpretation of spectroscopic experiments and the simulation of particular observables. Thereby, we review all the studies of excited-state dynamics on transition metal complexes, both in gas phase and in solution from reduced to full dimensionality.
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Affiliation(s)
- J. Patrick Zobel
- Institute
of Theoretical Chemistry, Faculty of Chemistry, University of Vienna, Währingerstr. 19, 1090 Vienna Austria
| | - Leticia González
- Institute
of Theoretical Chemistry, Faculty of Chemistry, University of Vienna, Währingerstr. 19, 1090 Vienna Austria
- Vienna
Research Platform on Accelerating Photoreaction Discovery, University of Vienna, Währingerstr. 19, 1090 Vienna Austria
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41
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Wang X, Martínez-Fernández L, Zhang Y, Zhang K, Improta R, Kohler B, Xu J, Chen J. Solvent-Dependent Stabilization of a Charge Transfer State is the Key to Ultrafast Triplet State Formation in an Epigenetic DNA Nucleoside. Chemistry 2021; 27:10932-10940. [PMID: 33860588 DOI: 10.1002/chem.202100787] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Indexed: 11/10/2022]
Abstract
2'-Deoxy-5-formylcytidine (5fdCyd), a naturally occurring nucleoside found in mammalian DNA and mitochondrial RNA, exhibits important epigenetic functionality in biological processes. Because it efficiently generates triplet excited states, it is an endogenous photosensitizer capable of damaging DNA, but the intersystem crossing (ISC) mechanism responsible for ultrafast triplet state generation is poorly understood. In this study, time-resolved mid-IR spectroscopy and quantum mechanical calculations reveal the distinct ultrafast ISC mechanisms of 5fdCyd in water versus acetonitrile. Our experiment indicates that in water, ISC to triplet states occurs within 1 ps after 285 nm excitation. PCM-TD-DFT computations suggest that this ultrafast ISC is mediated by a singlet state with significant cytosine-to-formyl charge-transfer (CT) character. In contrast, ISC in acetonitrile proceeds via a dark 1 nπ* state with a lifetime of ∼3 ps. CT-induced ISC is not favored in acetonitrile because reaching the minimum of the gateway CT state is hampered by intramolecular hydrogen bonding, which enforces planarity between the aldehyde group and the aromatic group. Our study provides a comprehensive picture of the non-radiative decay of 5fdCyd in solution and new insights into the factors governing ISC in biomolecules. We propose that the intramolecular CT state observed here is a key to the excited-state dynamics of epigenetic nucleosides with modified exocyclic functional groups, paving the way to study their effects in DNA strands.
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Affiliation(s)
- Xueli Wang
- State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai, 200241, P. R. China
| | - Lara Martínez-Fernández
- Departamento de Química, Facultad de Ciencias and Institute for Advanced Research in Chemistry (IADCHEM), Universidad Autónoma de Madrid Campus de Excelencia UAM-CSIC Cantoblanco, 28049, Madrid, Spain
| | - Yuyuan Zhang
- Department of Chemistry and Biochemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio, 43210, USA
| | - Kun Zhang
- State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai, 200241, P. R. China
| | - Roberto Improta
- Istituto di Biostrutture e Bioimmagini CNR, Via Mezzocannone 16, 80134, Napoli, Italy
| | - Bern Kohler
- Department of Chemistry and Biochemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio, 43210, USA
| | - Jianhua Xu
- State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai, 200241, P. R. China.,Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan, Shanxi, 030006, P. R. China
| | - Jinquan Chen
- State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai, 200241, P. R. China.,Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan, Shanxi, 030006, P. R. China
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42
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Janicki M, Kufner CL, Todd ZR, Kim SC, O’Flaherty DK, Szostak JW, Šponer J, Góra RW, Sasselov DD, Szabla R. Ribose Alters the Photochemical Properties of the Nucleobase in Thionated Nucleosides. J Phys Chem Lett 2021; 12:6707-6713. [PMID: 34260253 PMCID: PMC9634911 DOI: 10.1021/acs.jpclett.1c01384] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Substitution of exocyclic oxygen with sulfur was shown to substantially influence the properties of RNA/DNA bases, which are crucial for prebiotic chemistry and photodynamic therapies. Upon UV irradiation, thionucleobases were shown to efficiently populate triplet excited states and can be involved in characteristic photochemistry or generation of singlet oxygen. Here, we show that the photochemistry of a thionucleobase can be considerably modified in a nucleoside, that is, by the presence of ribose. Our transient absorption spectroscopy experiments demonstrate that thiocytosine exhibits 5 times longer excited-state lifetime and different excited-state absorption features than thiocytidine. On the basis of accurate quantum chemical simulations, we assign these differences to the dominant population of a shorter-lived triplet nπ* state in the nucleoside and longer-lived triplet ππ* states in the nucleobase. This explains the distinctive photoanomerziation of thiocytidine and indicates that the nucleoside will be a less efficient phototherapeutic agent with regard to singlet oxygen generation.
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Affiliation(s)
- Mikołaj
J. Janicki
- Department
of Physical and Quantum Chemistry, Faculty of Chemistry, Wrocław University of Science and Technology, Wybrzeże Wyspiańskiego
27, 50-370 Wrocław, Poland
| | - Corinna L. Kufner
- Department
of Astronomy, Harvard-Smithsonian Center
for Astrophysics, 60 Garden Street, Cambridge, Massachusetts 02138, United States
| | - Zoe R. Todd
- Department
of Astronomy, Harvard-Smithsonian Center
for Astrophysics, 60 Garden Street, Cambridge, Massachusetts 02138, United States
| | - Seohyun C. Kim
- Howard
Hughes Medical Institute, Department of Molecular Biology and Center
for Computational and Integrative Biology, Massachusetts General Hospital, 185 Cambridge Street, Boston, Massachusetts 02114, United States
| | - Derek K. O’Flaherty
- Howard
Hughes Medical Institute, Department of Molecular Biology and Center
for Computational and Integrative Biology, Massachusetts General Hospital, 185 Cambridge Street, Boston, Massachusetts 02114, United States
| | - Jack W. Szostak
- Howard
Hughes Medical Institute, Department of Molecular Biology and Center
for Computational and Integrative Biology, Massachusetts General Hospital, 185 Cambridge Street, Boston, Massachusetts 02114, United States
| | - Jiří Šponer
- Institute
of Biophysics, Czech Academy of Sciences, Královopolská 135, 61265 Brno, Czech
Republic
- Regional
Centre of Advanced Technologies and Materials, Czech Advanced Technology
and Research Institute (CATRIN), Palacky
University Olomouc, Slechtitelu
241/27, 783 71 Olomouc-Holice, Czech Republic
| | - Robert W. Góra
- Department
of Physical and Quantum Chemistry, Faculty of Chemistry, Wrocław University of Science and Technology, Wybrzeże Wyspiańskiego
27, 50-370 Wrocław, Poland
| | - Dimitar D. Sasselov
- Department
of Astronomy, Harvard-Smithsonian Center
for Astrophysics, 60 Garden Street, Cambridge, Massachusetts 02138, United States
| | - Rafał Szabla
- EaStCHEM,
School of Chemistry, University of Edinburgh, Joseph Black Building, David Brewster
Road, Edinburgh EH9 3FJ, U.K.
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43
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Carmona-García J, Francés-Monerris A, Cuevas CA, Trabelsi T, Saiz-Lopez A, Francisco JS, Roca-Sanjuán D. Photochemistry and Non-adiabatic Photodynamics of the HOSO Radical. J Am Chem Soc 2021; 143:10836-10841. [PMID: 34270223 DOI: 10.1021/jacs.1c05149] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Hydroxysulfinyl radical (HOSO) is important due to its involvement in climate geoengineering upon SO2 injection and generation of the highly hygroscopic H2SO4. Its photochemical behavior in the upper atmosphere is, however, uncertain. Here we present the ultraviolet-visible photochemistry and photodynamics of this species by simulating the atmospheric conditions with high-level quantum chemistry methods. Photocleavage to HO + SO arises as the major solar-induced channel, with a minor contribution of H + SO2 photoproducts. The efficient generation of SO is relevant due to its reactivity with O3 and the consequent depletion of ozone in the stratosphere.
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Affiliation(s)
- Javier Carmona-García
- Institut de Ciència Molecular, Universitat de València, València 46071, Spain.,Department of Atmospheric Chemistry and Climate, Institute of Physical Chemistry Rocasolano, CSIC, Madrid 28006, Spain
| | - Antonio Francés-Monerris
- Departament de Química Física, Universitat de València, 46100 Burjassot, Spain.,Université de Lorraine, CNRS, LPCT, F-54000 Nancy, France
| | - Carlos A Cuevas
- Department of Atmospheric Chemistry and Climate, Institute of Physical Chemistry Rocasolano, CSIC, Madrid 28006, Spain
| | - Tarek Trabelsi
- Department of Earth and Environmental Sciences and Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Alfonso Saiz-Lopez
- Department of Atmospheric Chemistry and Climate, Institute of Physical Chemistry Rocasolano, CSIC, Madrid 28006, Spain
| | - Joseph S Francisco
- Department of Earth and Environmental Sciences and Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Daniel Roca-Sanjuán
- Institut de Ciència Molecular, Universitat de València, València 46071, Spain
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44
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Zhu YH, Zhang TS, Tang XF, Xie BB, Cui G. MS-CASPT2 studies on the mechanistic photophysics of tellurium-substituted guanine and cytosine. Phys Chem Chem Phys 2021; 23:12421-12430. [PMID: 34028476 DOI: 10.1039/d1cp01142a] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Sulfur-substituted nucleobases are highly promising photosensitizers that are widely used in photodynamic therapy, and there are numerous studies exploring their unique photophysical behaviors. However, relevant photophysical investigations on selenium and tellurium substitutions are still rare. Herein, the high-level multistate complete-active-space second-order perturbation (MS-CASPT2) method was performed for the first time to explore the excited-state relaxation processes of tellurium-substituted guanine (TeG) and cytosine (TeC). Based on the electronic state properties in the Franck-Condon (FC) region, we found that the lowest five (S0, S1, S2, T1, and T2) and six (S0, S1, S2, T1, T2 and T3) states will participate in the nonadiabatic transition processes of TeG and TeC systems, respectively. In these electronic states, two kinds of minimum and intersection structures (i.e., planar and twisted structures) were obtained for both TeG and TeC systems. The linearly interpolated internal coordinate (LIIC) paths and spin-orbit coupling (SOC) constants revealed several possible planar and twisted excited-state decay channels, which could lead the systems to the lowest reactive triplet state of T1. Small energy barriers in the T1 state will trap the TeG and TeC systems for a while before they finally populate to the ground state. Although tellurium substitution would further redshift the absorption wavelength and enhance the intersystem crossing (ISC) rate to the T1 state compared with sulfur and selenium substitutions, the rapid ISC process of T1 → S0 may make it a less effective photosensitizer to sensitize the molecular oxygen. We believe our present work will provide important mechanistic insights into the photophysics of tellurium-substituted nucleobases.
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Affiliation(s)
- Yun-Hua Zhu
- Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education College of Chemistry, Beijing Normal University, Beijing 100875, P. R. China.
| | - Teng-Shuo Zhang
- College of Chemical Engineering, Zhejiang University of Technology, Hangzhou 310014, Zhejiang, P. R. China
| | - Xiu-Fang Tang
- Hangzhou Institute of Advanced Studies, Zhejiang Normal University, 1108 Gengwen Road, Hangzhou 311231, Zhejiang, P. R. China.
| | - Bin-Bin Xie
- Hangzhou Institute of Advanced Studies, Zhejiang Normal University, 1108 Gengwen Road, Hangzhou 311231, Zhejiang, P. R. China.
| | - Ganglong Cui
- Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education College of Chemistry, Beijing Normal University, Beijing 100875, P. R. China.
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45
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Nguyen VN, Park SJ, Qi S, Ha J, Heo S, Yim Y, Baek G, Lim CS, Lee DJ, Kim HM, Yoon J. Design and synthesis of efficient heavy-atom-free photosensitizers for photodynamic therapy of cancer. Chem Commun (Camb) 2021; 56:11489-11492. [PMID: 32857074 DOI: 10.1039/d0cc04644b] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Novel thiocarbonyl derivatives (NIS and CRNS) with excellent ROS generation abilities are synthesized and studied as potential photosensitizers for one- and two-photon excited photodynamic therapy. In particular, NIS-Me and CRNS display outstanding phototoxicity toward HeLa cells under two-photon excitation (800 nm) with negligible dark toxicity.
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Affiliation(s)
- Van-Nghia Nguyen
- Institute of Research and Development, Duy Tan University, Da Nang 550000, Vietnam
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46
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Abstract
In this article, we review nonadiabatic molecular dynamics (NAMD) methods for modeling spin-crossover transitions. First, we discuss different representations of electronic states employed in the grid-based and direct NAMD simulations. The nature of interstate couplings in different representations is highlighted, with the main focus on nonadiabatic and spin-orbit couplings. Second, we describe three NAMD methods that have been used to simulate spin-crossover dynamics, including trajectory surface hopping, ab initio multiple spawning, and multiconfiguration time-dependent Hartree. Some aspects of employing different electronic structure methods to obtain information about potential energy surfaces and interstate couplings for NAMD simulations are also discussed. Third, representative applications of NAMD to spin crossovers in molecular systems of different sizes and complexities are highlighted. Finally, we pose several fundamental questions related to spin-dependent processes. These questions should be possible to address with future methodological developments in NAMD.
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Affiliation(s)
- Saikat Mukherjee
- Institut de Chimie Radicalaire, CNRS 7273, Aix-Marseille University, 13013 Marseille, France;
| | - Dmitry A Fedorov
- Oak Ridge Associated Universities, Oak Ridge, Tennessee 37830, USA;
| | - Sergey A Varganov
- Department of Chemistry, University of Nevada, Reno, Nevada 89557-0216, USA;
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47
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Heindl M, González L. Validating fewest-switches surface hopping in the presence of laser fields. J Chem Phys 2021; 154:144102. [PMID: 33858152 DOI: 10.1063/5.0044807] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
The capability of fewest-switches surface hopping (FSSH) to describe non-adiabatic dynamics under explicit excitation with external fields is evaluated. Different FSSH parameters are benchmarked against multi-configurational time dependent Hartree (MCTDH) reference calculations using SO2 and 2-thiocytosine as model, yet realistic, molecular systems. Qualitatively, FSSH is able to reproduce the trends in the MCTDH dynamics with (also without) an explicit external field; however, no set of FSSH parameters is ideal. The adequate treatment of the overcoherence in FSSH is revealed as the driving factor to improve the description of the excitation process with respect to the MCTDH reference. Here, two corrections were tested: the augmented-FSSH (AFSSH) correction and the energy-based decoherence correction. A dependence on the employed basis is detected in AFSSH, performing better when spin-orbit and external laser field couplings are treated as off-diagonal elements instead of projecting them onto the diagonal of the Hamilton operator. In the presence of an electric field, the excited state dynamics was found to depend strongly on the vector used to rescale the kinetic energy along after a transition between surfaces. For SO2, recurrence of the excited wave packet throughout the duration of the applied laser pulse is observed for laser pulses (>100 fs), resulting in additional interferences missed by FSSH and only visible in variational multi-configurational Gaussian when utilizing a large number of Gaussian basis functions. This feature vanishes when going toward larger molecules, such as 2-thiocytosine, where this effect is barely visible in a laser pulse 200 fs long.
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Affiliation(s)
- Moritz Heindl
- Institute of Theoretical Chemistry, Faculty of Chemistry, University of Vienna, Währingerstr. 17, 1090 Vienna, Austria
| | - Leticia González
- Institute of Theoretical Chemistry, Faculty of Chemistry, University of Vienna, Währingerstr. 17, 1090 Vienna, Austria
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48
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Valverde D, Mai S, Sanches de Araújo AV, Canuto S, González L, Borin AC. On the population of triplet states of 2-seleno-thymine. Phys Chem Chem Phys 2021; 23:5447-5454. [PMID: 33650609 DOI: 10.1039/d1cp00041a] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
The population and depopulation mechanisms leading to the lowest-lying triplet states of 2-Se-Thymine were studied at the MS-CASPT2/cc-pVDZ level of theory. Several critical points on different potential energy hypersurfaces were optimized, including minima, conical intersections, and singlet-triplet crossings. The accessibility of all relevant regions on the potential energy hypersurfaces was investigated by means of minimum energy paths and linear interpolation in internal coordinates techniques. Our analysis indicates that, after the population of the bright S2 state in the Franck-Condon region, the first photochemical event is a barrierless evolution towards one of its two minima. After that, three viable photophysical deactivation paths can take place. In one of them, the population in the S2 state is transferred to the T2 state via intersystem crossing and subsequently to the T1 state by internal conversion. Alternatively, the S1 state could be accessed by internal conversion through two distinct conical intersections with S2 state followed by singlet-triplet crossing with the T2 state. The absence of a second minimum on the T1 state and a small energy barrier on pathway along the potential energy surface towards the ground state from the lowest triplet state are attributed as potential reasons to explain why the lifetime of the triplet state of 2-Se-Thymine might be reduced in comparison with its thio-analogue.
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Affiliation(s)
- Danillo Valverde
- Institute of Physics, University of São Paulo, Rua do Matão 1371. 05508-090, São Paulo, SP, Brazil
| | - Sebastian Mai
- Photonics Institute, Vienna University of Technology, Gußhausstraße 27-29, 1040 Vienna, Austria and Institute of Theoretical Chemistry, Faculty of Chemistry, University of Vienna, Währinger Straße 17, 1090 Vienna, Austria.
| | | | - Sylvio Canuto
- Institute of Physics, University of São Paulo, Rua do Matão 1371. 05508-090, São Paulo, SP, Brazil
| | - Leticia González
- Institute of Theoretical Chemistry, Faculty of Chemistry, University of Vienna, Währinger Straße 17, 1090 Vienna, Austria.
| | - Antonio Carlos Borin
- Department of Fundamental Chemistry, Institute of Chemistry, University of São Paulo, Av. Prof. Lineu Prestes 748. 05508-000, São Paulo, SP, Brazil.
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49
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Euceda N, Jahnke J, Espinal A, Louis MF, Bashkin E, Roccanova P, Espaillat A, Fuentes GV, Nieto F, Gao R. Thioguanine restoration through type I photosensitization-superoxide oxidation-glutathione reduction cycles. Phys Chem Chem Phys 2021; 23:5069-5073. [PMID: 33655288 DOI: 10.1039/d1cp00101a] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
UVA-induced deleterious effect of thiopurine prodrugs including azathioprine, 6-mercaptopurine and 6-thioguanine (6-TG) increases the risk of cancer development due to the incorporation of 6-TG in patients' DNA. The catalytic mechanism by which thiobases act as a sustained oxidant producer has yet to be explored, especially through the Type I electron transfer pathway that produces superoxide radicals (O2˙-). Under Fenton-like conditions O2˙- radicals convert to extremely reactive hydroxyl radicals (˙OH), thus carrying even higher risk of biological damage than that induced by the well-studied type II reaction. By monitoring 6-TG/UVA-induced photochemistry in mass spectra and superoxide radicals (O2˙-) via nitro blue tetrazolium (NBT) reduction, this work provides two new findings: (1) in the presence of reduced glutathione (GSH), the production of O2˙-via the type I reaction is enhanced 10-fold. 6-TG thiyl radicals are identified as the primary intermediate formed in the reaction of 6-TG with O2˙-. The restoration of 6-TG and concurrent generation of O2˙- occur via a 3-step-cycle: 6-TG type I photosensitization, O2˙- oxidation and GSH reduction. (2) In the absence of GSH, 6-TG thiyl radicals undergo oxygen addition and sulfur dioxide removal to form carbon radicals (C6) which further convert to thioether by reacting with 6-TG molecules. These findings help explain not only thiol-regulation in a biological system but chemoprevention of cancer.
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Affiliation(s)
- Nelson Euceda
- Chemistry and Physics Department, SUNY College at Old Westbury, Old Westbury, NY 11568, USA.
| | - Joyce Jahnke
- Chemistry and Physics Department, SUNY College at Old Westbury, Old Westbury, NY 11568, USA.
| | - Aileen Espinal
- Chemistry and Physics Department, SUNY College at Old Westbury, Old Westbury, NY 11568, USA.
| | - Monique F Louis
- Chemistry and Physics Department, SUNY College at Old Westbury, Old Westbury, NY 11568, USA.
| | - Edan Bashkin
- Chemistry and Physics Department, SUNY College at Old Westbury, Old Westbury, NY 11568, USA.
| | - Patricia Roccanova
- Biological Sciences Department, SUNY College at Old Westbury, Old Westbury, NY 11568, USA
| | - Abraham Espaillat
- Chemistry and Physics Department, SUNY College at Old Westbury, Old Westbury, NY 11568, USA.
| | - German V Fuentes
- Chemistry and Physics Department, SUNY College at Old Westbury, Old Westbury, NY 11568, USA.
| | - Fernando Nieto
- Biological Sciences Department, SUNY College at Old Westbury, Old Westbury, NY 11568, USA
| | - Ruomei Gao
- Chemistry and Physics Department, SUNY College at Old Westbury, Old Westbury, NY 11568, USA.
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50
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Zhang K, Wang F, Jiang Y, Wang X, Pan H, Sun Z, Sun H, Xu J, Chen J. New Insights about the Photostability of DNA/RNA Bases: Triplet nπ* State Leads to Effective Intersystem Crossing in Pyrimidinones. J Phys Chem B 2021; 125:2042-2049. [PMID: 33600186 DOI: 10.1021/acs.jpcb.0c10611] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The high photostability of DNA/RNA nucleobases is attributed to the effective internal conversions of their bright 1ππ* states to the ground state through conical intersections. Intersystem crossing (ISC) from singlet to triplet excited states is a minor decay pathway in nucleobases and it is observed with ∼1-2% quantum yields (QYs) in pyrimidine bases. Presumably, ISC in pyrimidines takes place from the dark singlet 1nπ* state to the lowest triplet 3ππ* state. However, recent studies showed that ISC from the initial populated bright 1ππ* state to higher energy triplet 3nπ* states indeed occurs in the subpicosecond timescale. Such a mechanism is still poorly understood since direct observation of this pathway is challenging. Herein, excited state dynamics of three pyrimidinones, which share the same skeleton with pyrimidine bases, is investigated in different solvents. Compared to canonical pyrimidine bases, removing the oxygen atom at the C4 position revokes the low-lying dark 1nπ* state in pyrimidinones, resulting in direct ISC from the S1 (1ππ*) state to triplet T3 (3nπ*) state with much higher QYs. Meanwhile, hydrogen bonding between the carbonyl group in pyrimidinones and protic solvents can accelerate vibrational cooling of the hot S1 (1ππ*) state, leading to higher fluorescence QYs and smaller ISC rate constants. These results not only evidence the hypothesis of the direct 1ππ* → 3nπ* ISC mechanism, but also contribute to a better understanding of triplet formation in pyrimidines.
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Affiliation(s)
- Kun Zhang
- State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200241, China
| | - Fufang Wang
- State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200241, China
| | - Yanrong Jiang
- State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200241, China
| | - Xueli Wang
- State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200241, China
| | - Haifeng Pan
- State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200241, China
| | - Zhenrong Sun
- State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200241, China
| | - Haitao Sun
- State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200241, China
| | - Jianhua Xu
- State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200241, China.,Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan, Shanxi 030006, China
| | - Jinquan Chen
- State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200241, China.,Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan, Shanxi 030006, China
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