1
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Chen Z, Wang X, Jia M, He X, Pan H, Chen J. Ribose and Deoxyribose Group Alter Excited-State Dynamics of 5-Azacytosine in Solution. Photochem Photobiol 2024; 100:291-297. [PMID: 35993879 DOI: 10.1111/php.13696] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2022] [Accepted: 08/16/2022] [Indexed: 10/15/2022]
Abstract
5-Azacytosine (5-AC) is one of the best interesting noncanonical nucleobases due to its functionalization and structural imitation of natural bases. 5-AC can be used as the scaffold of two important chemotherapeutic medicines, 5-azacytidine and 2'-deoxy-5-azacytidine. Furthermore, increased sensitivity to UV leads to the photochemical effects of 5-AC also attracted attention. Yet, no study has been reported to explore the effect of glycosyl groups on the photophysical and photochemical properties of 5-AC, which can help to reveal the photostability of related actual clinic drugs. In this study, the excited-state dynamics of 5-azacytidine and 2'-deoxy-5-azacytidine are studied by femtosecond transient absorption and quantum-chemical calculations while revisiting that of 5-AC with a wider probe spectral range. It is shown that glycosyl substitution on the N1 position leads to ultrafast excited-state relaxation within several picoseconds in both nucleosides, which is distinct compared with the 17 ps lifetime seen in 5-AC. It is proposed that these changes are due to altering the energy level of the dark nπ* state. Moreover, our results suggest that it should be cautioned to simply replace sugar groups with methyl groups when doing a theoretical calculation study on nucleobases and their derivatives.
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Affiliation(s)
- Ziwei Chen
- State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai, China
| | - Xueli Wang
- State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai, China
| | - Menghui Jia
- State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai, China
| | - Xiaoxiao He
- State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai, China
| | - Haifeng Pan
- State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai, China
| | - Jinquan Chen
- State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai, China
- Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan, China
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2
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Chang XP, Fan FR, Zhang TS, Xie BB. Quantum mechanics/molecular mechanics studies on the excited-state decay mechanisms of cytidine aza-analogues: 5-azacytidine and 2'-deoxy-5-azacytidine in aqueous solution. Phys Chem Chem Phys 2023; 25:26258-26269. [PMID: 37743787 DOI: 10.1039/d3cp03628f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/26/2023]
Abstract
The excited state properties and deactivation pathways of two DNA methylation inhibitors, i.e., 5-azacytidine (5ACyd) and 2'-deoxy-5-azacytidine (5AdCyd) in aqueous solution, are comprehensively explored with the QM(CASPT2//CASSCF)/MM protocol. We systematically map the feasible decay mechanisms based on the obtained excited-state decay paths involving all the identified minimum-energy structures, conical intersections, and crossing points driving the different internal conversion (IC) and intersystem crossing (ISC) routes in and between the 1ππ*, 1nπ*, 3ππ*, 3nπ*, and S0 states. Unlike the 1nπ* state below the 1ππ* state in 5ACyd, deoxyribose group substitution at the N1 position leads to the 1ππ* state becoming the S1 state in 5AdCyd. In 5ACyd and 5AdCyd, the initially populated 1ππ* state mainly deactivates to the S0 state through the direct 1ππ* → S0 IC or mediated by the 1nπ* state. The former nearly barrierless IC channel of 1ππ* → S0 occurs ultrafast via the nearby low-lying 1ππ*/S0 conical intersection. In the latter IC channel of 1ππ* → 1nπ* → S0, the initially photoexcited 1ππ* state first approaches the nearby S2/S1 conical section 1ππ*/1nπ* and then undergoes efficient IC to the 1nπ* state, followed by the further IC to the initial S0 state via the S1/S0 conical intersection 1nπ*/S0. The 1nπ*/S0 conical intersection is estimated to be located 6.0 and 4.9 kcal mol-1 above the 1nπ* state minimum in 5ACyd and 5AdCyd, respectively, at the QM(CASPT2)/MM level. In addition to the efficient singlet-mediated IC channels, the minor ISC routes would populate 1ππ* to T1(ππ*) through 1ππ* → T1 or 1ππ* → 1nπ* → T1. Relatively, the 1ππ* → 1nπ* → T1 route benefits from the spin-orbit coupling (SOC) of 1nπ*/3ππ* of 8.7 cm-1 in 5ACyd and 10.2 cm-1 in 5AdCyd, respectively. Subsequently, the T1 system will approach the nearby T1/S0 crossing point 3ππ*/S0 driving it back to the S0 state. Given the 3ππ*/S0 crossing point located above the T1 minimum and the small T1/S0 SOC, i.e., 8.4 kcal mol-1 and 2.1 cm-1 in 5ACyd and 6.8 kcal mol-1 and 1.9 cm-1 in 5AdCyd, respectively, the slow T1 → S0 would trap the system in the T1 state for a while. The present work could contribute to understanding the mechanistic photophysics and photochemistry of similar aza-nucleosides and their derivatives.
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Affiliation(s)
- Xue-Ping Chang
- College of Chemistry and Chemical Engineering, Xinyang Normal University, Xinyang 464000, China.
| | - Feng-Ran Fan
- College of Chemistry and Chemical Engineering, Xinyang Normal University, Xinyang 464000, China.
| | - Teng-Shuo Zhang
- College of Chemical Engineering, Zhejiang University of Technology, Hangzhou 310014, China
| | - Bin-Bin Xie
- Hangzhou Institute of Advanced Studies, Zhejiang Normal University, Hangzhou 311231, China
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3
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Tichý O, Pederzoli M, Pittner J, Burda JV. Vertical Excitation Energies and Lifetimes of the Two Lowest Singlet Excited States of Cytosine, 5-Aza-cytosine, and the Triazine Family: Quantum Mechanics-Molecular Mechanics Studies. J Chem Theory Comput 2023; 19:1976-1985. [PMID: 36961980 PMCID: PMC10100535 DOI: 10.1021/acs.jctc.2c01262] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/26/2023]
Abstract
A swarm of semi-classical quantum mechanics/molecular mechanics molecular-dynamics simulations where OM2/MNDO is combined with the Gromacs program for consideration of explicit water is performed, solving the time-dependent Schrödinger equation in each step of the trajectories together with the Tully's fewest switches algorithm. Within this stochastic treatment, time dependent probabilities of the three lowest electronic states are determined. The fact that nucleobases are quickly deactivated is confirmed in the cytosine case where our best lifetime estimation is τ1=0.82 ps for the model with 100 water molecules with the SPCE force field and a time step of 0.1 fs. Lifetimes of the remaining molecules are visibly longer: 5-azacytosine, 2,4-diamino-1,3,5-triazine (DT), and 2,4,6-triamino-1,3,5-triazine (TT) molecules have an S1 → S0 de-excitation time of slightly above 10 ps. The lifetimes of the triazine family increases with the increasing number of exocyclic amino groups, that is, s-triazine < 2-amino-1,3,5-triazine < DT < TT. This can be explained by a higher mobility of the carbon-bonded hydrogen atoms in comparison with heavier amino groups since their movement is slowed down due to a substantially higher mass than hydrogen atoms, which can easier reach the out-of-plane positions required in the conical intersection structures. Moreover, bulkier NH2 ligands suffer due to greater friction caused by the surrounding water environment. These mechanical aspects caused a change in the explored lifetime dependences in comparison with our previous gas-phase study.
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Affiliation(s)
- Ondřej Tichý
- Department of Chemical Physics and Optics, Faculty of Mathematics and Physics, Charles University, Ke Karlovu 3, 121 16 Prague 2, Czech Republic
| | - Marek Pederzoli
- J. Heyrovský Institute of Physical Chemistry, Academy of Sciences, Dolejškova 3, 182 23 Prague 8, Czech Republic
| | - Jiří Pittner
- J. Heyrovský Institute of Physical Chemistry, Academy of Sciences, Dolejškova 3, 182 23 Prague 8, Czech Republic
| | - Jaroslav V Burda
- Department of Chemical Physics and Optics, Faculty of Mathematics and Physics, Charles University, Ke Karlovu 3, 121 16 Prague 2, Czech Republic
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4
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Chang XP, Zhao G, Zhang TS, Xie BB. Quantum mechanics/molecular mechanics studies on mechanistic photophysics of cytosine aza-analogues: 2,4-diamino-1,3,5-triazine and 2-amino-1,3,5-triazine in aqueous solution. Phys Chem Chem Phys 2023; 25:7669-7680. [PMID: 36857660 DOI: 10.1039/d2cp05639a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/15/2023]
Abstract
The excited-state properties and photophysics of cytosine aza-analogues, i.e., 2,4-diamino-1,3,5-triazine (2,4-DT) and 2-amino-1,3,5-triazine (2-AT) in solution have been systematically explored using the QM(MS-CASPT2//CASSCF)/MM approach. The excited-state nonradiative relaxation mechanisms for the initially photoexcited S1(ππ*) state decay back to the S0 state are proposed in terms of the present computed minima, surface crossings (conical intersections and singlet-triplet crossings), and excited-state decay paths in the S1, S2, T1, T2, and S0 states. Upon photoexcitation to the bright S1(ππ*) state, 2,4-DT quickly relaxes to its S1 minimum and then overcomes a small energy barrier of 5.1 kcal mol-1 to approach a S1/S0 conical intersection, where the S1 system hops to the S0 state through S1 → S0 internal conversion (IC). In addition, at the S1 minimum, the system could partially undergo intersystem crossing (ISC) to the T1 state, followed by further ISC to the S0 state via the T1/S0 crossing point. In the T1 state, an energy barrier of 7.9 kcal mol-1 will trap 2,4-DT for a while. In parallel, for 2-AT, the system first relaxes to the S1 minimum and then S1 → S0 IC or S1 → T1 → S0 ISCs take place to the S0 state by surmounting a large barrier of 15.3 kcal mol-1 or 11.9 kcal mol-1, respectively, which heavily suppress electronic transition to the S0 state. Different from 2,4-DT, upon photoexcitation in the Franck-Condon region, 2-AT can quickly evolve in an essentially barrierless manner to nearby S2/S1 conical intersection, where the S2 and T1 states can be populated. Once it hops to the S2 state, the system will overcome a relatively small barrier (6.6 kcal mol-1vs. 15.3 kcal mol-1) through IC to the S0 state. Similarly, an energy barrier of 11.9 kcal mol-1 heavily suppresses the T1 state transformation to the S0 state. The present work manifests that the amination/deamination of the triazine rings can affect some degree of different vertical and adiabatic excitation energies and nonradiative decay pathways in solution. It not only rationalizes excited-state decay dynamics of 2,4-DT and 2-AT in aqueous solution but could also provide insights into the understanding of the photophysics of aza-nucleobases.
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Affiliation(s)
- Xue-Ping Chang
- College of Chemistry and Chemical Engineering, Xinyang Normal University, Xinyang 464000, China.
| | - Geng Zhao
- College of Chemistry and Chemical Engineering, Xinyang Normal University, Xinyang 464000, China.
| | - Teng-Shuo Zhang
- College of Chemical Engineering, Zhejiang University of Technology, Hangzhou 310014, China
| | - Bin-Bin Xie
- Hangzhou Institute of Advanced Studies, Zhejiang Normal University, Hangzhou 311231, China
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5
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Giussani A, Worth GA. On the photorelease of nitric oxide by nitrobenzene derivatives: A CASPT2//CASSCF model. J Chem Phys 2022; 157:204301. [PMID: 36456224 DOI: 10.1063/5.0125460] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Nitroaromatic compounds can photorelease nitric oxide after UV absorption. The efficiency of the photoreaction depends on the molecular structure, and two features have been pointed out as particularly important for the yield of the process: the presence of methyl groups at the ortho position with respect to the nitro group and the degree of conjugation of the molecule. In this paper, we provide a theoretical characterization at the CASPT2//CASSCF (complete active space second-order perturbation theory//complete active space self-consistent field) level of theory of the photorelease of NO for four molecules derived from nitrobenzene through the addition of ortho methyl groups and/or the elongation of the conjugation. Our previously described mechanism obtained for the photorelease of NO in nitrobenzene has been adopted as a model for the process. According to this model, the process proceeds through a reactive singlet-triplet crossing (STC) region that the system can reach from the triplet 3(πOπ*) minimum. The energy barrier that must be surmounted in order to populate the reactive STC can be associated with the efficiency of the photoreaction. Here, the obtained results display clear differences in the efficiency of the photoreaction in the studied systems and can be correlated with experimental results. Thus, the model proves its ability to highlight the differences in the photoreaction efficiency for the nitroaromatic compounds studied here.
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Affiliation(s)
- Angelo Giussani
- Instituto de Ciencia Molecular, Universitat de València, Apartado22085, ES-46071 Valencia, Spain
| | - Graham A Worth
- Department of Chemistry, University College London, 20 Gordon Street, London WC1H 0AJ, United Kingdom
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6
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Cherneva TD, Todorova MM, Bakalska RI, Horkel E, Delchev VB. Non-radiative deactivation of excited cytosine: probing of different DFT functionals and basis sets in solvents with different polarity. J Mol Model 2022; 28:306. [PMID: 36085333 DOI: 10.1007/s00894-022-05313-6] [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: 06/17/2022] [Accepted: 08/30/2022] [Indexed: 11/28/2022]
Abstract
The vertical excitation and emission energies of the cytosine oxo-amino form were calculated at the TD DFT level of theory with several functionals, basis sets, and solvents with different polarity (PCM). They were compared with the experimental UV absorption and fluorescence maxima, revealing that the minimal deviation of the vertical excitation energies from the of UV absorption maxima can be achieved when the hybrid functional B3LYP is applied within the calculations. Regular correlations like curves with saturation between the vertical excitation/emission energies and the dielectric constants were registered. The relaxation of the 1ππ* excited state through an ethylene-like conical intersection S0/S1 should occur through decrease of the decay rate (commented qualitatively here) with the rise of the solvent polarity.
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Affiliation(s)
- T D Cherneva
- Faculty of Chemistry, University of Plovdiv, Tzar Assen 24 Str, Plovdiv, Bulgaria
| | - M M Todorova
- Faculty of Chemistry, University of Plovdiv, Tzar Assen 24 Str, Plovdiv, Bulgaria
| | - R I Bakalska
- Faculty of Chemistry, University of Plovdiv, Tzar Assen 24 Str, Plovdiv, Bulgaria
| | - E Horkel
- Inst. Applied Synthetic Chemistry, TU Wien, Getreidemarkt 9, 1060, Vienna, Austria
| | - V B Delchev
- Faculty of Chemistry, University of Plovdiv, Tzar Assen 24 Str, Plovdiv, Bulgaria.
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7
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Delchev VB, Shterev IG. CRYSTAL STRUCTURE AND PHOTOCHEMISTRY OF 5-AZACYTOSINE: EXPERIMENTAL AND THEORETICAL STUDY. J STRUCT CHEM+ 2022. [DOI: 10.1134/s0022476622030015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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8
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Tichý O, Burda JV. Estimation of electron absorption spectra and lifetime of the two lowest singlet excited states of pyrimidine nucleobases and their derivatives. J Mol Struct 2022. [DOI: 10.1016/j.molstruc.2021.131863] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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9
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Mikroulis T, Cuquerella MC, Giussani A, Pantelia A, Rodríguez-Muñiz GM, Rotas G, Roca-Sanjuán D, Miranda MA, Vougioukalakis GC. Building a Functionalizable, Potent Chemiluminescent Agent: A Rational Design Study on 6,8-Substituted Luminol Derivatives. J Org Chem 2021; 86:11388-11398. [PMID: 34350754 DOI: 10.1021/acs.joc.1c00890] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Luminol is a prominent chemiluminescent (CL) agent, finding applications across numerous fields, including forensics, immunoassays, and imaging. Different substitution patterns on the aromatic ring can enhance or decrease its CL efficiency. We herein report a systematic study on the synthesis and photophysics of all possible 6,8-disubstituted luminol derivatives bearing H, Ph, and/or Me substituents. Their CL responses are monitored at three pH values (8, 10, and 12), thus revealing the architecture with the optimum CL efficiency. The most efficient pattern is used for the synthesis of a strongly CL luminol derivative, bearing a functional group for further, straightforward derivatization. This adduct exhibits an unprecedented increase in chemiluminescence efficiency at pH = 12, pH = 10, and especially at pH = 8 (closer to the biologically relevant conditions) compared to luminol. Complementary work on the fluorescence of the emissive species as well as quantum chemistry computations are employed for the rationalization of the observed results.
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Affiliation(s)
- Theodoros Mikroulis
- Laboratory of Organic Chemistry, Department of Chemistry, National and Kapodistrian University of Athens, Panepistimiopolis, 15771 Athens, Greece
| | - M Consuelo Cuquerella
- Instituto de Tecnología Química, UPV-CSIC, Universitat Politècnica de València, Camino de Vera s/n, 46022 València, Spain
| | - Angelo Giussani
- Instituto de Ciencia Molecular, Universitat de València, P.O. Box 22085, 46071 València, Spain
| | - Anna Pantelia
- Laboratory of Organic Chemistry, Department of Chemistry, National and Kapodistrian University of Athens, Panepistimiopolis, 15771 Athens, Greece
| | - Gemma M Rodríguez-Muñiz
- Instituto de Tecnología Química, UPV-CSIC, Universitat Politècnica de València, Camino de Vera s/n, 46022 València, Spain
| | - Georgios Rotas
- Laboratory of Organic Chemistry, Department of Chemistry, National and Kapodistrian University of Athens, Panepistimiopolis, 15771 Athens, Greece
| | - Daniel Roca-Sanjuán
- Instituto de Ciencia Molecular, Universitat de València, P.O. Box 22085, 46071 València, Spain
| | - Miguel A Miranda
- Instituto de Tecnología Química, UPV-CSIC, Universitat Politècnica de València, Camino de Vera s/n, 46022 València, Spain
| | - Georgios C Vougioukalakis
- Laboratory of Organic Chemistry, Department of Chemistry, National and Kapodistrian University of Athens, Panepistimiopolis, 15771 Athens, Greece
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10
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Xu T, Hu Z, Lv M, Zhou Z, Xu J, Sun Z, Sun H, Chen J. Hydrogen atom and water complex determine the excited state dynamics of 8-azaguanine. Chem Phys 2021. [DOI: 10.1016/j.chemphys.2021.111118] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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11
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Giussani A, Worth GA. On the Intrinsically Low Quantum Yields of Pyrimidine DNA Photodamages: Evaluating the Reactivity of the Corresponding Minimum Energy Crossing Points. J Phys Chem Lett 2020; 11:4984-4989. [PMID: 32490676 DOI: 10.1021/acs.jpclett.0c01264] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
The low quantum yield of photoformation of cyclobutane pyrimidine dimers and pyrimidine-pyrimidone (6-4) adducts in DNA bases is usually associated with the presence of more favorable nonreactive decay paths and with the unlikeliness of exciting the system in a favorable conformation. Here, we prove that the ability of the reactive conical intersection to bring the system either back to the absorbing conformation or to the photoproduct must be considered as a fundamental factor in the low quantum yields of the mentioned photodamage. In support of the proposed model, the one order of magnitude difference in the quantum yield of formation of the cyclobutane thymine dimer with respect to the thymine-thymine (6-4) adduct is rationalized here by comparing the reactive ability of the seam of intersections leading respectively to the cyclobutane thymine dimer and the oxetane precursor of the thymine-thymine (6-4) adduct at the CASPT2 level of theory.
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Affiliation(s)
- Angelo Giussani
- Department of Chemistry, University College London, 20 Gordon Street, London WC1H 0AJ, U.K
| | - Graham A Worth
- Department of Chemistry, University College London, 20 Gordon Street, London WC1H 0AJ, U.K
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12
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Sanches de Araújo AV, Borin AC. Photochemical Relaxation Pathways of 9 H-8-Azaguanine and 8 H-8-Azaguanine. J Phys Chem A 2019; 123:3109-3120. [PMID: 30901221 DOI: 10.1021/acs.jpca.9b01397] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The photochemical reaction path approach, the MS-CASPT2 quantum-chemical method, and double-ζ basis sets (cc-pVDZ) were used to study 9 H-8-azaguanine and 8 H-8-azaguanine relaxation pathways. Several potential energy hypersurfaces were characterized by means of equilibrium geometries, surface crossings (conical intersections and singlet-triplet intersystem crossings), minimum energy paths, and linear interpolation in internal coordinates. The 9 H-8-azaguanine main photochemical event begins with the direct population of the 1(ππ* La) state, which evolves toward a conical intersection with the ground state after surmounting a small energy barrier, explaining why it is nonfluorescent. For 8 H-8-azaguanine, two relaxation mechanisms are possible, depending on the excitation energy. If the S1 1(ππ*) state is initially populated (lower-energy region), the system evolves barrierless to the S1 1(ππ*)min region, from where the excess energy is released. If the 1(ππ* La) state is populated (higher-energy radiation), the system will encounter conical intersections with the S2 1(nOπ*) and S1 1(ππ*) states before evolving to the 1(ππ* La)min region, from where a conical intersection with the ground state is accessible, favoring radiationless deactivation to the ground state. However, because a fraction of the population can be transferred from 1(ππ* La) to the S1 1(ππ*) state, emission from the S1 1(ππ*)min region is also expected, although weaker than it would be if the S1 1(ππ*) state were populated directly. Irrespective of the excitation energy, the emissive state is the same and a single fluorescence band is observed, with the strongest emission occurring upon excitation in the lower-energy region, as observed experimentally. Therefore, our computational study corroborates experimental results, attributing the emission of the neutral form of 8-azaguanine in solution to the presence of the minor 8 H-8-azaguanine tautomer, while the 9 H-8-azaguanine major tautomer is nonfluorescent.
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Affiliation(s)
| | - 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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13
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Giussani A, Farahani P, Martínez‐Muñoz D, Lundberg M, Lindh R, Roca‐Sanjuán D. Molecular Basis of the Chemiluminescence Mechanism of Luminol. Chemistry 2019; 25:5202-5213. [PMID: 30720222 DOI: 10.1002/chem.201805918] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2018] [Revised: 01/22/2019] [Indexed: 02/03/2023]
Affiliation(s)
- Angelo Giussani
- Institut de Ciència MolecularUniversitat de València P.O. Box 22085 València Spain
| | - Pooria Farahani
- Department of Theoretical Chemistry & Biology, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH)KTH Royal Institute of Technology 10691 Stockholm Sweden
| | - Daniel Martínez‐Muñoz
- Department of Chemistry-Ångström LaboratoryUppsala University P.O. Box 538 75121 Uppsala Sweden
| | - Marcus Lundberg
- Department of Chemistry-Ångström LaboratoryUppsala University P.O. Box 538 75121 Uppsala Sweden
| | - Roland Lindh
- Department of Chemistry-Ångström LaboratoryUppsala University P.O. Box 538 75121 Uppsala Sweden
| | - Daniel Roca‐Sanjuán
- Institut de Ciència MolecularUniversitat de València P.O. Box 22085 València Spain
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14
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Giussani A, Worth GA. Similar chemical structures, dissimilar triplet quantum yields: a CASPT2 model rationalizing the trend of triplet quantum yields in nitroaromatic systems. Phys Chem Chem Phys 2019; 21:10514-10522. [DOI: 10.1039/c9cp00705a] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
S1/S0 accessibility strongly influences the triplet quantum yields of nitronaphthalenes.
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Affiliation(s)
- Angelo Giussani
- Department of Chemistry
- University College London
- London WC1H 0AJ
- UK
| | - Graham A. Worth
- Department of Chemistry
- University College London
- London WC1H 0AJ
- UK
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15
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Giussani A, Worth GA. Insights into the Complex Photophysics and Photochemistry of the Simplest Nitroaromatic Compound: A CASPT2//CASSCF Study on Nitrobenzene. J Chem Theory Comput 2017; 13:2777-2788. [DOI: 10.1021/acs.jctc.6b01149] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Angelo Giussani
- School
of Chemistry, University of Birmingham, Edgbaston B15 2TT, U.K
- Department
of Chemistry, University College London, 20 Gordon Street, London WC1H 0AJ, U.K
| | - Graham A. Worth
- School
of Chemistry, University of Birmingham, Edgbaston B15 2TT, U.K
- Department
of Chemistry, University College London, 20 Gordon Street, London WC1H 0AJ, U.K
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16
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Mato J, Keipert K, Gordon MS. Excited state properties of 5-formylcytosine and 5-hydroxymethylcytosine. Mol Phys 2017. [DOI: 10.1080/00268976.2017.1311424] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
- Joani Mato
- Department of Chemistry and Ames Laboratory, Iowa State University, Ames, IA, United States
| | - Kristopher Keipert
- Department of Chemistry and Ames Laboratory, Iowa State University, Ames, IA, United States
| | - Mark S. Gordon
- Department of Chemistry and Ames Laboratory, Iowa State University, Ames, IA, United States
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17
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Zhou Z, Zhou X, Wang X, Jiang B, Li Y, Chen J, Xu J. Ultrafast Excited-State Dynamics of Cytosine Aza-Derivative and Analogues. J Phys Chem A 2017; 121:2780-2789. [DOI: 10.1021/acs.jpca.6b12290] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Affiliation(s)
- Zhongneng Zhou
- State
Key Laboratory of Precision Spectroscopy, East China Normal University, 3663 North Zhongshan Road, Shanghai 200062, China
| | - Xueyao Zhou
- Department
of Chemical Physics, University of Science and Technology of China, Hefei 230026, China
| | - Xueli Wang
- State
Key Laboratory of Precision Spectroscopy, East China Normal University, 3663 North Zhongshan Road, Shanghai 200062, China
| | - Bin Jiang
- Department
of Chemical Physics, University of Science and Technology of China, Hefei 230026, China
| | - Yongle Li
- Department
of Physics, International Center of Quantum and Molecular Structures,
Shanghai Key Laboratory of High Temperature Superconductors, Shanghai University, Shanghai 200444, China
| | - Jinquan Chen
- State
Key Laboratory of Precision Spectroscopy, East China Normal University, 3663 North Zhongshan Road, Shanghai 200062, China
| | - Jianhua Xu
- State
Key Laboratory of Precision Spectroscopy, East China Normal University, 3663 North Zhongshan Road, Shanghai 200062, China
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18
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Carlos Borin A, Mai S, Marquetand P, González L. Ab initio molecular dynamics relaxation and intersystem crossing mechanisms of 5-azacytosine. Phys Chem Chem Phys 2017; 19:5888-5894. [DOI: 10.1039/c6cp07919a] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Nonadiabatic SHARC dynamics simulations reveal the molecular deformations involved in the photodeactivation pathways of 5-azacytosine.
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Affiliation(s)
- Antonio Carlos Borin
- Department of Fundamental Chemistry
- Institute of Chemistry
- University of São Paulo
- NAP-PhotoTech the USP Consortium for Photochemical Technology
- São Paulo
| | - Sebastian Mai
- Institute of Theoretical Chemistry
- Faculty of Chemistry
- University of Vienna
- 1090 Vienna
- Austria
| | - Philipp Marquetand
- Institute of Theoretical Chemistry
- Faculty of Chemistry
- University of Vienna
- 1090 Vienna
- Austria
| | - Leticia González
- Institute of Theoretical Chemistry
- Faculty of Chemistry
- University of Vienna
- 1090 Vienna
- Austria
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19
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Further studies into the photodissociation pathways of phenylperoxyl radicals. COMPUT THEOR CHEM 2015. [DOI: 10.1016/j.comptc.2015.06.028] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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20
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Liu Y, Guan P, Wang Y, Liu L, Cao J. Mechanistic Insight into Decomposition of 2H-Azirines: Electronic Structure Calculations and Dynamics Simulations. J Phys Chem A 2014; 119:67-78. [DOI: 10.1021/jp511208p] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Affiliation(s)
- Ye Liu
- Key
Laboratory of Theoretical and Computational Photochemistry, Ministry
of Education, College of Chemistry, Beijing Normal University, Beijing 100875, China
| | - Peijie Guan
- Key
Laboratory of Theoretical and Computational Photochemistry, Ministry
of Education, College of Chemistry, Beijing Normal University, Beijing 100875, China
| | - Yating Wang
- Key
Laboratory of Theoretical and Computational Photochemistry, Ministry
of Education, College of Chemistry, Beijing Normal University, Beijing 100875, China
| | - Lihong Liu
- Key
Laboratory of Theoretical and Computational Photochemistry, Ministry
of Education, College of Chemistry, Beijing Normal University, Beijing 100875, China
| | - Jun Cao
- Key
Laboratory of Theoretical and Computational Photochemistry, Ministry
of Education, College of Chemistry, Beijing Normal University, Beijing 100875, China
- Guizhou
Provincial Key Laboratory of Computational Nano-material Science, Guizhou Normal College, Guiyang, Guizhou 550018, China
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