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Tamarit L, El Ouardi M, Lence E, Andreu I, González-Bello C, Vayá I, Miranda MA. Switching from ultrafast electron transfer to proton transfer in excited drug–protein complexes upon biotransformation. Chem Sci 2022; 13:9644-9654. [PMID: 36091919 PMCID: PMC9400592 DOI: 10.1039/d2sc03257k] [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: 06/10/2022] [Accepted: 08/02/2022] [Indexed: 11/23/2022] Open
Abstract
Photosensitization by drugs is directly related with the excited species and the photoinduced processes arising from interaction with UVA light. In this context, the ability of gefitinib (GFT), a tyrosine kinase inhibitor (TKI) used for the treatment of a variety of cancers, to induce phototoxicity and photooxidation of proteins has recently been demonstrated. In principle, photodamage can be generated not only by a given drug but also by its photoactive metabolites that maintain the relevant chromophore. In the present work, a complete study of O-desmorpholinopropyl gefitinib (GFT-MB) has been performed by means of fluorescence and ultrafast transient absorption spectroscopies, in addition to molecular dynamics (MD) simulations. The photobehavior of the GFT-MB metabolite in solution is similar to that of GFT. However, when the drug or its metabolite are in a constrained environment, i.e. within a protein, their behavior and the photoinduced processes that arise from their interaction with UVA light are completely different. For GFT in complex with human serum albumin (HSA), locally excited (LE) singlet states are mainly formed; these species undergo photoinduced electron transfer with Tyr and Trp. By contrast, since GFT-MB is a phenol, excited state proton transfer (ESPT) to form phenolate-like excited species might become an alternative deactivation pathway. As a matter of fact, the protein-bound metabolite exhibits higher fluorescence yields and longer emission wavelengths and lifetimes than GFT@HSA. Ultrafast transient absorption measurements support direct ESPT deprotonation of LE states (rather than ICT), to form phenolate-like species. This is explained by MD simulations, which reveal a close interaction between the phenolic OH group of GFT-MB and Val116 within site 3 (subdomain IB) of HSA. The reported findings are relevant to understand the photosensitizing properties of TKIs and the role of biotransformation in this type of adverse side effects. The photoinduced processes from the protein-bound GFT result in electron transfer, while those related with the photoactive metabolite GFT-MB induce excited state proton transfer to form phenolate-like excited species.![]()
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Affiliation(s)
- Lorena Tamarit
- Departamento de Química/Instituto de Tecnología Química UPV-CSIC, Universitat Politècnica de València, Camino de Vera s/n, 46022 València, Spain
- Instituto de Investigación Sanitaria La Fe, Hospital Universitari i Politècnic La Fe, Avenida de Fernando Abril Martorell 106, 46026 Valencia, Spain
| | - Meryem El Ouardi
- Departamento de Química/Instituto de Tecnología Química UPV-CSIC, Universitat Politècnica de València, Camino de Vera s/n, 46022 València, Spain
- Instituto de Investigación Sanitaria La Fe, Hospital Universitari i Politècnic La Fe, Avenida de Fernando Abril Martorell 106, 46026 Valencia, Spain
| | - Emilio Lence
- Centro Singular de Investigación en Química Biolóxica e Materiais Moleculares (CiQUS), Departamento de Química Orgánica, Universidade de Santiago de Compostela, Jenaro de la Fuente s/n, 15782 Santiago de Compostela, Spain
| | - Inmaculada Andreu
- Departamento de Química/Instituto de Tecnología Química UPV-CSIC, Universitat Politècnica de València, Camino de Vera s/n, 46022 València, Spain
- Instituto de Investigación Sanitaria La Fe, Hospital Universitari i Politècnic La Fe, Avenida de Fernando Abril Martorell 106, 46026 Valencia, Spain
| | - Concepción González-Bello
- Centro Singular de Investigación en Química Biolóxica e Materiais Moleculares (CiQUS), Departamento de Química Orgánica, Universidade de Santiago de Compostela, Jenaro de la Fuente s/n, 15782 Santiago de Compostela, Spain
| | - Ignacio Vayá
- Departamento de Química/Instituto de Tecnología Química UPV-CSIC, Universitat Politècnica de València, Camino de Vera s/n, 46022 València, Spain
- Instituto de Investigación Sanitaria La Fe, Hospital Universitari i Politècnic La Fe, Avenida de Fernando Abril Martorell 106, 46026 Valencia, Spain
| | - Miguel A. Miranda
- Departamento de Química/Instituto de Tecnología Química UPV-CSIC, Universitat Politècnica de València, Camino de Vera s/n, 46022 València, Spain
- Instituto de Investigación Sanitaria La Fe, Hospital Universitari i Politècnic La Fe, Avenida de Fernando Abril Martorell 106, 46026 Valencia, Spain
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Tamarit L, El Ouardi M, Andreu I, Vayá I, Miranda MA. Photoprocesses of the tyrosine kinase inhibitor gefitinib: from femtoseconds to microseconds and from solution to cells. Chem Sci 2021; 12:12027-12035. [PMID: 34667568 PMCID: PMC8457384 DOI: 10.1039/d1sc03154f] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2021] [Accepted: 07/13/2021] [Indexed: 01/05/2023] Open
Abstract
Gefitinib (GFT) is a tyrosine kinase inhibitor currently used for the treatment of metastatic non-small cell lung cancer. Although it has been suggested that GFT can be phototoxic, there are no systematic studies on this issue. Here, the photosensitizing potential of GFT has been assessed by means of NRU assays and protein photooxidation. In addition, a thorough photophysical study is presented based on ultrafast transient absorption spectroscopy, fluorescence and laser flash photolysis. Transient species generated after excitation of GFT have been characterized in solution and in biological environments (i.e. HSA and HaCaT cells) to gain insight into the mechanisms involved in photodamage. The photobehavior of GFT was strongly medium-dependent. Excitation of the drug resulted in the formation of locally excited (LE) singlet states (1GFT*), which were found to be the main emissive species in non-polar solvents and also within HSA and HaCaT cells. By contrast, in polar solvents, LE states rapidly evolved (∼1 ps) towards the formation of longer-lived intramolecular charge transfer (ICT) states. The triplet excited state of GFT (3GFT*) can be formed through intersystem crossing from 1GFT* in non-polar solvents and from ICT states in the polar ones, or in the particular case of ethanol, by photosensitization using 2-methoxyacetophenone as an energy donor. In the HSA environment, 3GFT* was hardly detected due to quenching of its LE 1GFT* precursor by Trp through an electron transfer process. Accordingly, HSA photooxidation by GFT was demonstrated using the protein carbonylation method. In summary, a good correlation is established between the photophysical behavior and the photobiological properties of GFT, which provides a mechanistic basis for the observed phototoxicity. Excitation of gefitinib leads to the formation of locally excited (LE) and/or charge transfer (ICT) states in the ps scale. In solution, both can evolve to the excited triplet state. In proteins, quenching of LE by electron donors leads to oxidation.![]()
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Affiliation(s)
- Lorena Tamarit
- Departamento de Química/Instituto de Tecnología Química UPV-CSIC, Universitat Politècnica de València Camino de Vera s/n 46022 València Spain .,Unidad Mixta de Investigación, Universitat Politècnica de València, Instituto de Investigación Sanitaria (IIS) La Fe, Hospital Universitari i Politècnic La Fe Avenida de Fernando Abril Martorell 106 46026 València Spain
| | - Meryem El Ouardi
- Departamento de Química/Instituto de Tecnología Química UPV-CSIC, Universitat Politècnica de València Camino de Vera s/n 46022 València Spain .,Unidad Mixta de Investigación, Universitat Politècnica de València, Instituto de Investigación Sanitaria (IIS) La Fe, Hospital Universitari i Politècnic La Fe Avenida de Fernando Abril Martorell 106 46026 València Spain
| | - Inmaculada Andreu
- Departamento de Química/Instituto de Tecnología Química UPV-CSIC, Universitat Politècnica de València Camino de Vera s/n 46022 València Spain .,Unidad Mixta de Investigación, Universitat Politècnica de València, Instituto de Investigación Sanitaria (IIS) La Fe, Hospital Universitari i Politècnic La Fe Avenida de Fernando Abril Martorell 106 46026 València Spain
| | - Ignacio Vayá
- Departamento de Química/Instituto de Tecnología Química UPV-CSIC, Universitat Politècnica de València Camino de Vera s/n 46022 València Spain .,Unidad Mixta de Investigación, Universitat Politècnica de València, Instituto de Investigación Sanitaria (IIS) La Fe, Hospital Universitari i Politècnic La Fe Avenida de Fernando Abril Martorell 106 46026 València Spain
| | - Miguel A Miranda
- Departamento de Química/Instituto de Tecnología Química UPV-CSIC, Universitat Politècnica de València Camino de Vera s/n 46022 València Spain .,Unidad Mixta de Investigación, Universitat Politècnica de València, Instituto de Investigación Sanitaria (IIS) La Fe, Hospital Universitari i Politècnic La Fe Avenida de Fernando Abril Martorell 106 46026 València Spain
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El-Agamey A, Melø TB, El-Hagrasy MA, Partali V, Fukuzumi S. Carotenoid radical ions: A laser flash photolysis study. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY. B, BIOLOGY 2020; 212:112023. [PMID: 32980657 DOI: 10.1016/j.jphotobiol.2020.112023] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/06/2020] [Revised: 09/02/2020] [Accepted: 09/04/2020] [Indexed: 10/23/2022]
Abstract
Laser excitation of a single precursor, namely 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylpropiophenone (HHEMP), has been used for generating the radical cations and radical anions of various carotenoids in methanol. In the presence of oxygen, laser excitation of HHEMP undergoes an efficient α-cleavage reaction (Norrish type I) to form acyl radicals, which react with O2, in a nearly diffusion-controlled reaction, to form their corresponding strong oxidizing acylperoxyl radicals (RO2•) (E = ~1.1 V (v SHE)), which are capable of oxidizing almost all carotenoids. Under argon-saturated conditions and in the presence of strong base (0.01 M NaOH or tetrabutylammonium hydroxide (TBAOH)), the initially formed 2-hydroxy-2-propyl radical (ACH•), generated after LFP of HHEMP, is deprotonated to form the strong reducing acetone ketyl radical (AC•-) (E {acetone/ AC•-} = -2.1 V (v SHE)), which is capable of reducing all carbonyl-containing carotenoids. To validate this new proposed approach, retinal and β-apo-8'-carotenal (APO), with known spectroscopic data, were investigated in methanol, acetonitrile and tetrahydrofuran (THF). In addition, the radical ions of newly investigated carotenoids, namely 4-oxo-β-apo-15'-carotenoic acid (4-oxo-15'), crocetindial, 4-oxo-β-apo-10'-carotenoic acid ethyl ester (4-oxo-10') and 4-oxo-β-apo-8'-carotenoic acid ethyl ester (4-oxo-8') have been reported. Moreover, the scope of this approach has been extended to investigate the radical ions of chlorophyll b.
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Affiliation(s)
- Ali El-Agamey
- Department of Physics, Norwegian University of Science and Technology (NTNU), N-7491 Trondheim, Norway; Chemistry Department, Faculty of Science, Damietta University, New Damietta, Damietta, Egypt; Department of Chemistry, Faculty of Science, King Faisal University, Al-Ahsa, Saudi Arabia.
| | - Thor B Melø
- Department of Physics, Norwegian University of Science and Technology (NTNU), N-7491 Trondheim, Norway
| | - Maha A El-Hagrasy
- Chemistry Department, Faculty of Science, Damietta University, New Damietta, Damietta, Egypt
| | - Vassilia Partali
- Department of Chemistry, Norwegian University of Science and Technology (NTNU), N-7491 Trondheim, Norway
| | - Shunichi Fukuzumi
- Department of Chemistry and Nano Science, Ewha Womans University, Seoul 120-750, Republic of Korea; Faculty of Science and Technology, Meijo University, ALCA and SENTAN, Japan Science and Technology Agency (JST), Nagoya, Aichi 468-8502, Japan
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4
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Tsubone TM, Zhang Z, Goyal R, Santacruz C, Martins WK, Kohn J, Baptista MS. Porphyrin-Loaded TyroSpheres for the Intracellular Delivery of Drugs and Photoinduced Oxidant Species. Mol Pharm 2020; 17:2911-2924. [DOI: 10.1021/acs.molpharmaceut.0c00338] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Tayana Mazin Tsubone
- Department of Biochemistry, Institute of Chemistry, University of São Paulo, São Paulo 05508-900, Brazil
| | - Zheng Zhang
- New Jersey Center for Biomaterials, Rutgers, The State University of New Jersey, Piscataway, New Jersey 08854-8009, United States
| | - Ritu Goyal
- New Jersey Center for Biomaterials, Rutgers, The State University of New Jersey, Piscataway, New Jersey 08854-8009, United States
| | - Carolina Santacruz
- Department of Biochemistry, Institute of Chemistry, University of São Paulo, São Paulo 05508-900, Brazil
| | | | - Joachim Kohn
- New Jersey Center for Biomaterials, Rutgers, The State University of New Jersey, Piscataway, New Jersey 08854-8009, United States
| | - Mauricio S. Baptista
- Department of Biochemistry, Institute of Chemistry, University of São Paulo, São Paulo 05508-900, Brazil
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Katagi T. Direct photolysis mechanism of pesticides in water. JOURNAL OF PESTICIDE SCIENCE 2018; 43:57-72. [PMID: 30363143 PMCID: PMC6140697 DOI: 10.1584/jpestics.d17-081] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2017] [Accepted: 01/13/2018] [Indexed: 05/14/2023]
Abstract
Photodegradation is one of the most important abiotic transformations for pesticides in the aquatic environment, and the high energy of sunlight causes characteristic reactions such as bond scission, cyclization, and rearrangement, which are scarcely observed in hydrolysis and microbial degradation. This review deals with direct photolysis via excitation of a pesticide by absorbing natural or artificial sunlight in order to know its basic photochemistry, and indirect photolysis meaning either sensitization by dissolved organic matters or oxidation by reactive oxygen species is basically excluded. Several experimental approaches including spectroscopic techniques together with theoretical calculations are first discussed from the viewpoint of the reaction mechanisms in direct photolysis. Then, the typical photoreactions of pesticides are summarized by chemical classes and/or functional groups and discussed as far as possible in relation to their mechanisms.
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Affiliation(s)
- Toshiyuki Katagi
- Environmental Health Science Laboratory, Sumitomo Chemical Co., Ltd
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6
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Durantini AM, Greene LE, Lincoln R, Martínez SR, Cosa G. Reactive Oxygen Species Mediated Activation of a Dormant Singlet Oxygen Photosensitizer: From Autocatalytic Singlet Oxygen Amplification to Chemicontrolled Photodynamic Therapy. J Am Chem Soc 2016; 138:1215-25. [DOI: 10.1021/jacs.5b10288] [Citation(s) in RCA: 114] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- Andrés M. Durantini
- Department
of Chemistry and Center for Self-Assembled Chemical Structures (CSACS-CRMAA), McGill University, 801 Sherbrooke Street West, Montreal, Quebec H3A 0B8, Canada
| | - Lana E. Greene
- Department
of Chemistry and Center for Self-Assembled Chemical Structures (CSACS-CRMAA), McGill University, 801 Sherbrooke Street West, Montreal, Quebec H3A 0B8, Canada
| | - Richard Lincoln
- Department
of Chemistry and Center for Self-Assembled Chemical Structures (CSACS-CRMAA), McGill University, 801 Sherbrooke Street West, Montreal, Quebec H3A 0B8, Canada
| | - Sol R. Martínez
- Department
of Chemistry and Center for Self-Assembled Chemical Structures (CSACS-CRMAA), McGill University, 801 Sherbrooke Street West, Montreal, Quebec H3A 0B8, Canada
- Instituto
Multidisciplinario de Biología Vegetal (IMBIV), CONICET, and
Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba X5000HUA, Argentina
| | - Gonzalo Cosa
- Department
of Chemistry and Center for Self-Assembled Chemical Structures (CSACS-CRMAA), McGill University, 801 Sherbrooke Street West, Montreal, Quebec H3A 0B8, Canada
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Sveen C, Macia N, Zaremberg V, Heyne B. Unveiling the Triplet State of a 4-Amino-7-Nitrobenzofurazan Derivative in Cyclohexane. Photochem Photobiol 2015; 91:272-9. [DOI: 10.1111/php.12402] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2014] [Accepted: 12/08/2014] [Indexed: 11/28/2022]
Affiliation(s)
| | - Nicolas Macia
- Department of Chemistry; University of Calgary; Calgary AB Canada
| | - Vanina Zaremberg
- Department of Biological Sciences; University of Calgary; Calgary AB Canada
| | - Belinda Heyne
- Department of Chemistry; University of Calgary; Calgary AB Canada
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Ahmad W. Photoinduced Aromatization of Asymmetrically Substituted 1,4-Dihydropyridine Derivative Drug Cilnidipine. INTERNATIONAL JOURNAL OF PHOTOCHEMISTRY 2014. [DOI: 10.1155/2014/176989] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
The antihypertensive drug Cilnidipine (1) is photolabile under UV-A light. Irradiation of a chloroform solution of Cilnidipine under aerobic and anaerobic conditions produces a common photoproduct which was isolated as 2-methoxyethyl-3-phenyl-2-propenyl pyridine dihydro-2,6-dimethyl-4-(3-nitrophenyl) pyridine-3,5-dicarboxylate (2). The formation of products was explained by photochemical aromatization of Cilnidipine.
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Affiliation(s)
- Waseem Ahmad
- Organic Chemistry Section, Department of Chemistry, Uttaranchal University, Dehradun 248001, India
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Kong X, Feng S, Zhang X, Li Y. Effects of bile salts and divalent cations on the adsorption of norfloxacin by agricultural soils. J Environ Sci (China) 2014; 26:846-854. [PMID: 25079415 DOI: 10.1016/s1001-0742(13)60480-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2013] [Revised: 07/29/2013] [Accepted: 09/03/2013] [Indexed: 06/03/2023]
Abstract
The effects of bile salts (sodium cholate and sodium deoxycholate, 0-20 mmol/L), divalent cations (Ca(2+), Mg(2+), Cu(2+) and Zn(2+), 0-20 mmol/L) or pH (3.0-10.0) on the adsorption of norfloxacin by three selected soils (Paddy_H, Paddy_G and Red_J) were systematically studied. Soil adsorption of norfloxacin follows a pseudo second-order kinetics model, and the maximum adsorption capacity has been determined from the nonlinear fit of the Langmuir isotherm model to be 88.8, 88.1 and 63.0 μmol/g for the adsorption onto Paddy_H, Paddy_G and Red_J, respectively. The results indicate that norfloxacin has a high adsorption affinity for the agricultural soils tested and that the organic content of these soils have at least a slight influence on this adsorption. The adsorption of norfloxacin to soils was strongly dependent on pH and exhibited a maximum at approximately pH 6. The presence of divalent cations prominently suppressed the adsorption of norfloxacin by paddy soils, which followed an order of Cu(2+) > Mg(2+) > Ca(2+) > Zn(2+), and by red soil, which followed an order of Cu(2+) > Zn(2+) > Ca(2+) > Mg(2+). The adsorption of norfloxacin (by the soils studied) sharply decreased as the amount of bile salts was increased. For uncharged norfloxacin at environmentally relevant pH values, such factors as soil type, exogenous divalent cations and macromolecules significantly altered the environmental fate and transport of norfloxacin between aquatic and soil interfaces.
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Affiliation(s)
- Xuesong Kong
- School of Resources and Environmental Science, Wuhan University, Wuhan 430079, China.
| | - Shixiang Feng
- School of Resources and Environmental Science, Wuhan University, Wuhan 430079, China
| | - Xu Zhang
- School of Resources and Environmental Science, Wuhan University, Wuhan 430079, China.
| | - Yan Li
- School of Resources and Environmental Science, Wuhan University, Wuhan 430079, China
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Bacellar IOL, Pavani C, Sales EM, Itri R, Wainwright M, Baptista MS. Membrane Damage Efficiency of Phenothiazinium Photosensitizers. Photochem Photobiol 2014; 90:801-13. [DOI: 10.1111/php.12264] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2013] [Accepted: 02/21/2014] [Indexed: 12/31/2022]
Affiliation(s)
- Isabel O. L. Bacellar
- Departamento de Bioquímica; Instituto de Química; Universidade de São Paulo; São Paulo Brasil
| | - Christiane Pavani
- Departamento de Bioquímica; Instituto de Química; Universidade de São Paulo; São Paulo Brasil
| | - Elisa M. Sales
- Departamento de Física Aplicada; Instituto de Física; Universidade de São Paulo; São Paulo Brasil
- Instituto de Pesquisas Tecnológicas do Estado de São Paulo; São Paulo Brasil
| | - Rosangela Itri
- Departamento de Física Aplicada; Instituto de Física; Universidade de São Paulo; São Paulo Brasil
| | - Mark Wainwright
- School of Pharmacy and Biomolecular Sciences; Liverpool John Moores University; Liverpool UK
| | - Mauricio S. Baptista
- Departamento de Bioquímica; Instituto de Química; Universidade de São Paulo; São Paulo Brasil
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11
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Piñero-Santiago LE, García C, Lhiaubet-Vallet V, Trzcionka J, Oyola R, Torres K, Leguillú J, Miranda MA. Photooxidation mechanism of levomepromazine in different solvents. Photochem Photobiol 2013; 89:1479-89. [PMID: 23909411 DOI: 10.1111/php.12147] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2013] [Accepted: 07/17/2013] [Indexed: 12/16/2022]
Abstract
Unwanted photoinduced responses are well-known adverse effects of most promazine drugs, including levomepromazine (LPZ, Levoprome(®) or Nozinan(®)). This drug is indicated in psychiatry primarily for the treatment of schizophrenia and other schizoaffective disorders. Levomepromazine's particular sedative properties make it especially fit for use in psychiatric intensive care. Nevertheless, it is photolabile under UV-A and UV-B light in aerobic conditions resulting in the formation of its sulfoxide. The LPZ photochemistry in acetonitrile (MeCN) is completely different from that in methanol (MeOH) and phosphate buffer solutions (PBS, pH = 7.4). The major photoproduct in PBS and MeOH under aerobic conditions is levomepromazine sulfoxide (LPZSO), although the amount is considerably higher in the aqueous environment. The corresponding main photoproduct in MeCN could not be characterized. The destruction quantum yields of LPZ in PBS, MeOH and MeCN are 0.13, 0.02 and <10(-3), respectively. It is further demonstrated that LPZSO does not form by the reaction of singlet oxygen with ground-state LPZ. This oxidation product is actually produced by the reaction of the cation radical of LPZ (LPZ·(+)) with molecular oxygen. This cation radical in turn, is produced by an electron transfer process between the (3) LPZ* and ground-state molecular oxygen.
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Affiliation(s)
- Luis E Piñero-Santiago
- Department of Chemistry, University of Puerto Rico at Humacao, Humacao, PR; Instituto de Tecnología Química UPV-CSIC, Universitat Politècnica de València, Valencia, Spain
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12
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Frenette M, Cosa G, Friščić T. Characterisation of organic solid forms and real-time in situ monitoring of their transformations using solid-state fluorescence. CrystEngComm 2013. [DOI: 10.1039/c3ce40604k] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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13
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Bohne C, Mitchell RH. Characterization of the photochromism of dihydropyrenes with photophysical techniques. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY C-PHOTOCHEMISTRY REVIEWS 2011. [DOI: 10.1016/j.jphotochemrev.2011.08.001] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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14
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Du B, Daniels VR, Vaksman Z, Boyd JL, Crady C, Putcha L. Evaluation of physical and chemical changes in pharmaceuticals flown on space missions. AAPS J 2011; 13:299-308. [PMID: 21479701 PMCID: PMC3085701 DOI: 10.1208/s12248-011-9270-0] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2010] [Accepted: 03/24/2011] [Indexed: 11/30/2022] Open
Abstract
Efficacy and safety of medications used for the treatment of astronauts in space may be compromised by altered stability in space. We compared physical and chemical changes with time in 35 formulations contained in identical pharmaceutical kits stowed on the International Space Station (ISS) and on Earth. Active pharmaceutical content (API) was determined by ultra- and high-performance liquid chromatography after returning to Earth. After stowage for 28 months in space, six medications aboard the ISS and two of matching ground controls exhibited changes in physical variables; nine medications from the ISS and 17 from the ground met the United States Pharmacopeia (USP) acceptance criteria for API content after 28 months of storage. A higher percentage of medications from each flight kit had lower API content than the respective ground controls. The number of medications failing API requirement increased as a function of time in space, independent of expiration date. The rate of degradation was faster in space than on the ground for many of the medications, and most solid dosage forms met USP standard for dissolution after storage in space. Cumulative radiation dose was higher and increased with time in space, whereas temperature and humidity remained similar to those on the ground. Exposure to the chronic low dose of ionizing radiation aboard the spacecraft as well as repackaging of solid dosage forms in flight-specific dispensers may adversely affect stability of pharmaceuticals. Characterization of degradation profiles of unstable formulations and identification of chemical attributes of stability in space analog environments on Earth will facilitate development of space-hardy medications.
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Affiliation(s)
- Brian Du
- />Wyle Integrated Science and Engineering Group, 1290 Hercules Drive, Suite 120, Houston, Texas 77058–2769 USA
| | - Vernie R. Daniels
- />Wyle Integrated Science and Engineering Group, 1290 Hercules Drive, Suite 120, Houston, Texas 77058–2769 USA
| | - Zalman Vaksman
- />Texas Medical Center, University of Texas, Houston, Texas 77025 USA
| | - Jason L. Boyd
- />Universities Space Research Association, Houston, Texas 77058 USA
| | - Camille Crady
- />Wyle Integrated Science and Engineering Group, 1290 Hercules Drive, Suite 120, Houston, Texas 77058–2769 USA
| | - Lakshmi Putcha
- />Pharmacotherapeutics Laboratory, SK/Human Adaptation and Countermeasures Division, NASA Johnson Space Center, 2101 NASA Parkway, Houston, Texas 77058 USA
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Santiago LEP, García C, Lhiaubet-Vallet V, Miranda MA, Oyola R. Solvent dependence of the photophysical properties of 2-chlorothioxanthone, the principal photoproduct of chlorprothixene. Photochem Photobiol 2011; 87:611-7. [PMID: 21294748 DOI: 10.1111/j.1751-1097.2011.00906.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
2-chlorothioxanthone (CTX) is used as photoinitiator for the reticulation of synthetic resins and for the preparation of pharmaceuticals. It was previously determined that CTX is the primary photoproduct of z-chlorprothixene (CPTX) when irradiated at 313 nm and is formed in an autocatalyzed reaction through an energy-transfer mechanism (Piñero et al. [2009] Photochem. Photobiol., 85, 895-900). In this work, the photophysical properties of CTX were measured in acetonitrile/water solutions to determine if their magnitude can affect the side effects of CPTX. The results show that CTX has higher absorption coefficients in the visible region (400-420 nm) and higher triplet quantum yields than its parent compound. Similar to TX, both properties strongly depend on the solvent polarity/hydroxylicity. The quantum yield of the triplet intermediate is very close to the value of the phenothiazine triplets. The phenothiazines are the most phototoxic antidepressants. Therefore, given the appropriate microenvironment, the photosensitization side effects of CPTX can be intensified on the production of CTX.
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Affiliation(s)
- Luis E Piñero Santiago
- Instituto de Tecnología Química UPV-CSIC, Universidad Politécnica de Valencia, Valencia, Spain
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16
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Arce R, Pino EF, Valle C, Negrón-Encarnación I, Morel M. A comparative photophysical and photochemical study of nitropyrene isomers occurring in the environment. J Phys Chem A 2011; 115:152-60. [PMID: 21162566 PMCID: PMC3020990 DOI: 10.1021/jp108652p] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Ground state absorption, first excited-singlet state, and properties of reactive intermediates of mononitropyrene isomers encountered in the atmospheric aerosol have been studied under different conditions that could mimic the environment. The nitro group can present different orientations relative to the pyrene ring depending on its geometric location and could induce differences in the photochemistry of the isomers. The 2-NO(2)Py isomer has the largest red shift and lowest oscillator strength in the UV-visible band associated with the nitro group. The isomers show very low fluorescence yields (10(-3)-10(-4)). Only 1-NO(2)Py and 4-NO(2)Py have phosphorescence emission (Φ(p) ≈ 10(-4)), indicating that the lowest triplet state decays mainly through effective radiationless channels. Laser photolysis produces a low-lying triplet state (τ(T) = 10(-5)-10(-6) s), a long-lived pyrenoxy radical, and a PyNO(2)H radical in solvents in which the triplet can abstract a hydrogen atom. Similar triplet yields were calculated (0.1-0.6) for the isomers, while significant differences in the relative yield of the long-lived species were determined. Differences in the quenching rate constants of the triplet by water and phenols suggest a strong hydrogen-bond interaction with the nitro group in the C-2 position, which provides for radiationless deactivation routes.
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Affiliation(s)
- Rafael Arce
- Department of Chemistry, University of Puerto Rico, Rio Piedras Campus, San Juan, Puerto Rico.
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17
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Muthukrishnan S, Sankaranarayanan J, Klima RF, Pace TCS, Bohne C, Gudmundsdottir AD. Intramolecular H-Atom Abstraction in γ-Azido-Butyrophenones: Formation of 1,5 Ketyl Iminyl Radicals. Org Lett 2009; 11:2345-8. [DOI: 10.1021/ol900754a] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Sivaramakrishnan Muthukrishnan
- Department of Chemistry, University of Cincinnati, PO Box 210172, Cincinnati, Ohio 45221, and Department of Chemistry, University of Victoria, Victoria, Canada V8W 3V6
| | - Jagadis Sankaranarayanan
- Department of Chemistry, University of Cincinnati, PO Box 210172, Cincinnati, Ohio 45221, and Department of Chemistry, University of Victoria, Victoria, Canada V8W 3V6
| | - Rodney F. Klima
- Department of Chemistry, University of Cincinnati, PO Box 210172, Cincinnati, Ohio 45221, and Department of Chemistry, University of Victoria, Victoria, Canada V8W 3V6
| | - Tamara C. S. Pace
- Department of Chemistry, University of Cincinnati, PO Box 210172, Cincinnati, Ohio 45221, and Department of Chemistry, University of Victoria, Victoria, Canada V8W 3V6
| | - Cornelia Bohne
- Department of Chemistry, University of Cincinnati, PO Box 210172, Cincinnati, Ohio 45221, and Department of Chemistry, University of Victoria, Victoria, Canada V8W 3V6
| | - Anna D. Gudmundsdottir
- Department of Chemistry, University of Cincinnati, PO Box 210172, Cincinnati, Ohio 45221, and Department of Chemistry, University of Victoria, Victoria, Canada V8W 3V6
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18
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Krumova K, Oleynik P, Karam P, Cosa G. Phenol-Based Lipophilic Fluorescent Antioxidant Indicators: A Rational Approach. J Org Chem 2009; 74:3641-51. [PMID: 19364120 DOI: 10.1021/jo900335z] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Katerina Krumova
- Department of Chemistry, McGill University, 801 Sherbrooke Street West, Montreal, QC H3A 2K6, Canada
| | - Paul Oleynik
- Department of Chemistry, McGill University, 801 Sherbrooke Street West, Montreal, QC H3A 2K6, Canada
| | - Pierre Karam
- Department of Chemistry, McGill University, 801 Sherbrooke Street West, Montreal, QC H3A 2K6, Canada
| | - Gonzalo Cosa
- Department of Chemistry, McGill University, 801 Sherbrooke Street West, Montreal, QC H3A 2K6, Canada
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19
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Montanaro S, Lhiaubet-Vallet V, Iesce MI, Previtera L, Miranda MA. A mechanistic study on the phototoxicity of atorvastatin: singlet oxygen generation by a phenanthrene-like photoproduct. Chem Res Toxicol 2009; 22:173-78. [PMID: 18989938 DOI: 10.1021/tx800294z] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Atorvastatin calcium (ATV) is one of the most frequently prescribed drugs worldwide. Among the adverse effects observed for this lipid-lowering agent, clinical cases of cutaneous adverse reactions have been reported and associated with photosensitivity disorders. Previous work dealing with ATV photochemistry has shown that exposure to natural sunlight in aqueous solution leads to photoproducts resulting from oxidation of the pyrrole ring and from cyclization to a phenanthrene derivative. Laser flash photolysis of ATV, at both 266 and 308 nm, led to a transient spectrum with two maxima at lambda= 360 and lambda= 580 nm (tau= 41 micro), which was assigned to the primary intermediate of the stilbene-like photocyclization. On the basis of the absence of a triplet-triplet absorption, the role of the parent drug as singlet oxygen photosensitizer can be discarded. By contrast, a stable phenanthrene-like photoproduct would be a good candidate to play this role. Laser flash photolysis of this compound showed a triplet-triplet transient absorption at lambdamax = 460 nm with a lifetime of 26 micro, which was efficiently quenched by oxygen (kq = 3 (+/-0.2) x 10(9) M(-1) s(-1)). Its potential to photosensitize formation of singlet oxygen was confirmed by spin trapping experiments, through conversion of TEMP to the stable free radical TEMPO. The photoreactivity of the phenanthrene-like photoproduct was investigated using Trp as a marker. The disappearance of the amino acid fluorescence (lambdamax = 340 nm) after increasing irradiation times at 355 nm was taken as a measurement of photodynamic oxidation. To confirm the involvement of a type II mechanism, the same experiment was also performed in D2O; this resulted in a significant enhancement of the reaction rate. On the basis of the obtained photophysical and photochemical results, the phototoxicity of atorvastatin can be attributed to singlet oxygen formation with the phenanthrene-like photoproduct as a photosensitizer.
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Affiliation(s)
- Sara Montanaro
- Instituto de Tecnologia Quimica, UPV-CSIC, UniVersidad Polité cnica de Valencia, AVenida de Los Naranjos, s/n, 46022, Valencia, Spain
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20
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Vieira Ferreira LF, Costa AI, Ferreira Machado I, Botelho do Rego AM, Sikorska E, Sikorski M. Surface photochemistry: alloxazine within nanochannels of Na+ and H+ ZSM-5 zeolites. Phys Chem Chem Phys 2009; 11:5762-72. [DOI: 10.1039/b903013a] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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21
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Arce R, Pino EF, Valle C, Ágreda J. Photophysics and Photochemistry of 1-Nitropyrene. J Phys Chem A 2008; 112:10294-304. [DOI: 10.1021/jp803051x] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Rafael Arce
- Department of Chemistry, University of Puerto Rico, Rio Piedras Campus, San Juan, Puerto Rico 00931-3346
| | - Eduardo F. Pino
- Department of Chemistry, University of Puerto Rico, Rio Piedras Campus, San Juan, Puerto Rico 00931-3346
| | - Carlos Valle
- Department of Chemistry, University of Puerto Rico, Rio Piedras Campus, San Juan, Puerto Rico 00931-3346
| | - Jésus Ágreda
- Department of Chemistry, University of Puerto Rico, Rio Piedras Campus, San Juan, Puerto Rico 00931-3346
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22
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Lorenzo F, Navaratnam S, Edge R, Allen NS. Primary Photophysical Properties of Moxifloxacin- A Fluoroquinolone Antibiotic. Photochem Photobiol 2008; 84:1118-25. [DOI: 10.1111/j.1751-1097.2007.00269.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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23
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Abbruzzetti S, Bruno S, Faggiano S, Ronda L, Grandi E, Mozzarelli A, Viappiani C. Characterization of ligand migration mechanisms inside hemoglobins from the analysis of geminate rebinding kinetics. Methods Enzymol 2008; 437:329-45. [PMID: 18433636 DOI: 10.1016/s0076-6879(07)37017-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/04/2023]
Abstract
The presence of internal hydrophobic cavities and packing defects has been demonstrated for several small globular proteins, including hemoglobins. The reduced thermodynamic stability appears to be compensated for by the capability of controlling ligand diffusion through the protein matrix to the active site, possibly by stocking more than one reactant molecule in selected sites. Photolysis of carbon monoxide complexes of hemoglobins encapsulated in silica gels leads to multiphasic geminate rebinding kinetics at room temperature, reflecting rebinding also from different temporary docking sites inside the protein matrix. A careful analysis of the ligand rebinding kinetics allows the determination of the microscopic rates for the underlying reactions, including those governing the migration to and from the docking sites. This chapter describes the experimental approach used to characterize the ligand rebinding kinetics for heme proteins in silica gels after nanosecond laser flash photolysis and the computational methods necessary to retrieve the kinetic parameters.
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Cosa G, Scaiano JC. Reactivity of adrenaline toward alkoxyl radicals and carbonyl triplet states. Org Biomol Chem 2008; 6:4609-14. [DOI: 10.1039/b810765c] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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25
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Klima RF, Jadhav AV, Singh PND, Chang M, Vanos C, Sankaranarayanan J, Vu M, Ibrahim N, Ross E, McCloskey S, Murthy RS, Krause JA, Ault BS, Gudmundsdóttir AD. Photoinduced C−N Bond Cleavage in 2-Azido-1,3-diphenyl-propan-1-one Derivatives: Photorelease of Hydrazoic Acid. J Org Chem 2007; 72:6372-81. [PMID: 17655357 DOI: 10.1021/jo070558q] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Photolysis of 3-azido-1,3-diphenyl-propan-1-one (1a) in toluene yields 1,3-diphenyl-propen-1-one (2), whereas irradiation of 3-azido-2,2-dimethyl-1,3-diphenyl-propan-1-one (1b) results in the formation of mainly 2,2-dimethyl-1,3-diphenyl-propan-1-one. Laser flash photolysis (308 nm) of 1a,b in acetonitrile reveals a transient absorption (lambda max = approximately 310 nm) due to the formation of radicals 4a and 4b, respectively, which have lifetimes of approximately 14 micros at ambient temperature. TD-DFT calculations (B3LYP/6-31+G(d)) reveal that the first and second excited states of the triplet ketone (T1K (n,pi*) and T2K (pi,pi*)) in azide 1a are almost degenerate, at approximately 74 and 76 kcal/mol above the ground state (S0), respectively. Similarly, azide 1b has T1K and T2K 75 and 82 kcal/mol above S0, respectively. The calculated transition state for cleaving the C-N bond is located 71 and 74 kcal/mol above S0 in azides 1a and 1b, respectively. The calculated bond dissociation energies for breaking the C-N bond are 55 and 58 kcal/mol for azides 1a and 1b, respectively, making C-N bond breakage accessible from T1K in azides 1 at ambient temperature. In comparison, the irradiation of azides 1 in argon matrices at 14 K lead to the formation of the corresponding triplet alkyl nitrenes (1-n), via intramolecular energy transfer from T2K. The characterization of 1-n was supported by isotope labeling, IR spectroscopy, and molecular modeling.
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Affiliation(s)
- Rodney F Klima
- Department of Chemistry, University of Cincinnati, Cincinnati, Ohio 45221-0172, USA
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26
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Pizarro N, Günther G, Núñez-Vergara LJ. Photophysical and photochemical behavior of nimodipine and felodipine. J Photochem Photobiol A Chem 2007. [DOI: 10.1016/j.jphotochem.2007.01.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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27
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Muthukrishnan S, Mandel SM, Hackett JC, Singh PND, Hadad CM, Krause JA, Gudmundsdóttir AD. Competition between α-Cleavage and Energy Transfer in α-Azidoacetophenones. J Org Chem 2007; 72:2757-68. [PMID: 17373846 DOI: 10.1021/jo062160k] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Molecular modeling demonstrates that the first excited state of the triplet ketone (T1K) in azide 1b has a (pi,pi*) configuration with an energy that is 66 kcal/mol above its ground state and its second excited state (T2K) is 10 kcal/mol higher in energy and has a (n,pi*) configuration. In comparison, T1K and T2K of azide 1a are almost degenerate at 74 and 77 kcal/mol above the ground state with a (n,pi*) and (pi,pi*) configuration, respectively. Laser flash photolysis (308 nm) of azide 1b in methanol yields a transient absorption (lambdamax=450 nm) due to formation of T1K, which decays with a rate of 2.1 x 105 s-1 to form triplet alkylnitrene 2b (lambdamax=320 nm). The lifetime of nitrene 2b was measured to be 16 ms. In contrast, laser flash photolysis (308 nm) of azide 1a produced transient absorption spectra due to formation of nitrene 2a (lambdamax=320 nm) and benzoyl radical 3a (lambdamax=370 nm). The decay of 3a is 2 x 105 s-1 in methanol, whereas nitrene 2a decays with a rate of approximately 91 s-1. Thus, T1K (pi,pi*) in azide 1b leads to energy transfer to form nitrene 2b; however, alpha-cleavage is not observed since the energy of T2K (n,pi*) is 10 kcal/mol higher in energy than T1K, and therefore, T2K is not populated. In azide 1a both alpha-cleavage and energy transfer are observed from T1K (n,pi*) and T2K (pi,pi*), respectively, since these triplet states are almost degenerate. Photolysis of azide 1a yields mainly product 4, which must arise from recombination of benzoyl radicals 3a with nitrenes 2a. However, products studies for azide 1b also yield 4b as the major product, even though laser flash photolysis of azide 1b does not indicate formation of benzoyl radical 3b. Thus, we hypothesize that benzoyl radicals 3 can also be formed from nitrenes 2. More specifically, nitrene 2 does undergo alpha-photocleavage to form benzoyl radicals and iminyl radicals. The secondary photolysis of nitrenes 2 is further supported with molecular modeling and product studies.
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Abbruzzetti S, Bruno S, Faggiano S, Grandi E, Mozzarelli A, Viappiani C. Time-resolved methods in Biophysics. 2. Monitoring haem proteins at work with nanosecond laser flash photolysis. Photochem Photobiol Sci 2006; 5:1109-20. [PMID: 17136275 DOI: 10.1039/b610236k] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Haem proteins have long been the most studied proteins in biophysics, and have become paradigms for the characterization of fundamental biomolecular processes as ligand binding and regulatory conformational transitions. The presence of the haem prosthetic group, the absorbance spectrum of which has a ligation sensitive region conveniently located in the UV-visible range, has offered a powerful and sensitive tool for the investigation of molecular functions. The central Fe atom is capable of reversibly binding diatomic ligands, including O(2), CO, and NO. The Fe-ligand bond is photolabile, and a reactive unligated state can be transiently generated with a pulsed laser. The photodissociated ligands quickly rebind to the haem and the process can be monitored by transient absorbance methods. The ligand rebinding kinetics reflects protein dynamics and ligand migration within the protein inner cavities. The characterization of these processes was done in the past mainly by low temperature experiments. The use of silica gels to trap proteins allows the characterization of internal ligand dynamics at room temperature. In order to show the potential of the laser flash photolysis techniques, combined with modern numerical analysis methods, we report experiments conducted on two non-symbiotic haemoglobins from Arabidopsis thaliana. The comparison between time courses recorded on haemoglobins in solution and encapsulated in silica gels allows for the highlighting of different interplays between protein dynamics and ligand migration.
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29
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Laser literature watch. Photomed Laser Surg 2006; 24:424-53. [PMID: 16875454 DOI: 10.1089/pho.2006.24.424] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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