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This document is the Accepted Manuscript version of a Published Work that appeared in final form in ACS Catalysis, copyright ©2018 American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see https://pubs.acs.org/doi/abs/10.1021/acscatal.8b01331 ; A bifunctional photoaminocatalyst based on imidazolidinone and thioxanthone is presented. The preparation of these catalysts proceeds in a two-step synthesis that allows an easy tuning of the steric properties. The photophysical and electrochemical data of the imidazolidinone photocatalysts have been determined, indicating that the catalysts can work under visible light conditions. To corroborate the experimental observations, ground state geometry optimization and energy transition studies of thioxanthone and bifunctional catalyst 4c were optimized by time-dependent density functional theory (TD DFT) calculations. The alkylation of aldehydes with this photoaminocatalyst works with high enantioselectivities and yields due to the stereoelectronic properties of the catalyst. A rational mechanistic cycle based on different mechanistic experiments, TD DFT calculations, and laser flash photolysis is presented ; The Spanish Government (CTQ2015-64561-R) and the European Research Council (ERC-CG, Contract 647550) are acknowledged

[EN] Latent electrophiles are nowadays very attractive chemical entities for drug discovery, as they are unreactive unless activated upon binding with the specific target. In this work, the utility of 4-trifluoromethyl phenols as precursors of latent electrophiles, quinone methides (QM), for lysine-targeting is demonstrated. These Michael acceptors were photogenerated for specific covalent modification of lysine residues using human serum albumin (HSA) as a model target. The reactive QM-type intermediates I or II, generated upon irradiation of 4-trifluoromethyl-1-naphthol (1)@HSA or 4-(4-trifluorometylphenyl)phenol (2)@HSA complexes, exhibited chemoselective reactivity toward lysine residues leading to amide adducts, which was confirmed by proteomic analysis. For ligand 1, the covalent modification of residues Lys106 and Lys414 (located in subdomains IA and IIIA, respectively) was observed, whereas for ligand 2, the modification of Lys195 (in subdomain IIA) took place. Docking and molecular dynamics simulation studies provided an insight into the molecular basis of the selectivity of 1 and 2 for these HSA subdomains and the covalent modification mechanism. These studies open the opportunity of performing protein silencing by generating reactive ligands under very mild conditions (irradiation) for specific covalent modification of hidden lysine residues. ; Financial support from the Spanish Ministry of Economy and Competiveness [CTQ2016-78875-P, SAF2016-75638-R and BES-2014-069404 (predoctoral fellowship to O.M.-M.)], the Generalitat Valenciana (PROMETEO/2017/075), the Community of Madrid (2016-T1/AMB-1275), the Xunta de Galicia (Centro Singular de Investigacion de Galicia accreditation 2016-2019, ED431G/09 and postdoctoral fellowship to E.L.), and the European Union (European Regional Development Fund, ERDF) is gratefully acknowledged. The proteomic analysis was performed in the proteomics facility of SCSIE University of Valencia that belongs to ProteoRed PRB2-ISCIII and is supported by grant PT13/0001, of the ...

The authors thank the European Research Council under the European Union's Seventh Framework Program (FP7/20072013)/ERC grant agreement no 340863 and ERC PoC LACRYS (837874) as well as Junta de Andalucia for financing the project P18-FR-5008. HC thanks the Deutsche Forschungsgemeinschaft DFG for financial support of the work on Biomorphs (CO 194/28-1). M.M., A.M., and A.M.-P. thank MIUR, (PRIN 2017) 2017E44A9P. Open access funding enabled and organized by Projekt DEAL. ; Photochemical activation is proposed as a general method for controlling the crystallization of sparingly soluble carbonates in space and time. The photogeneration of carbonate in an alkaline environment is achieved upon photo-decarboxylation of an organic precursor by using a conventional 365 nm UV LED. Local irradiation was conducted focusing the LED light on a 300 μm radius spot on a closed glass crystallization cell. The precursor solution was optimized to avoid the precipitation of the photoreaction organic byproducts and prevent photo-induced pH changes to achieve the formation of calcium carbonate only in the corresponding irradiated area. The crystallization was monitored in real-time by time-lapse imaging. The method is also shown to work in gels. Similarly, it was also shown to photo-activate locally the formation of barium carbonate biomorphs. In the last case, the morphology of these biomimetic structures was tuned by changing the irradiation intensity. ; European Research Council under the European Union's Seventh Framework Program (FP7/20072013)/ERC grant 340863 ; ERC PoC LACRYS 837874 ; Junta de Andalucia P18-FR-5008 ; German Research Foundation (DFG) CO 194/28-1 ; Ministry of Education, Universities and Research (MIUR) ; Research Projects of National Relevance (PRIN) 2017E44A9P ; Projekt DEAL

A new photoactive Pt (II) hydroxyquinoline complex has been covalently linked into the structure of an imine-based layered covalent organic framework (COF) through the monomer truncation strategy. Such strategy allows the incorporation of molecular fragments with only one functional group able to condensate into the imine-framework. The photocatalytic activity of the resulting Pt@COF has been applied to the oxidation of sulfides to sulfoxides, obtaining excellent results for all the studied cases, and showing that this reaction goes through both photoredox and energy transfer processes. The results obtained showed a great enhancement of the catalytic activity (up to 25000 turnover number, TON), stability and a significant decrease on the reaction times, as a consequence of immobilization and isolation of Pt(II) centers into the organic framework. In addition, Pt@COF has been proved to be an excellent heterogeneous photocatalyst also in exclusive photoredox processes, reaching 7500 TON in hydrodebromination reactions ; We are grateful to the Spanish Government (RTI2018-095038-B-I00), "Comunidad de Madrid" and European Structural Funds (S2018/NMT-4367). A.E.P.-P. acknowledges a TALENTO grant (2017-T1/IND5148) from Comunidad de Madrid and Spanish Government (RTI2018-096138-A-I00)

This document is the Accepted Manuscript version of a Published Work that appeared in final form in ACS Photonics, copyright © 2017 American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see http://doi.org/10.1021/acsphotonics.7b00680 ; We present an overview of the general concepts of polaritonic chemistry with organic molecules, i.e., the manipulation of chemical structure that can be achieved through strong coupling between confined light modes and organic molecules. Strong coupling and the associated formation of polaritons, hybrid light-matter excitations, lead to energy shifts in such systems that can amount to a large fraction of the uncoupled transition energy. This has recently been shown to significantly alter the chemical structure of the coupled molecules, which opens the possibility to manipulate and control reactions. We discuss the current state of theory for describing these changes and present several applications, with a particular focus on the collective effects observed when many molecules are involved in strong coupling ; This work has been funded by the European Research Council under grant agreements ERC-2011-AdG-290981 and ERC-2016-STG- 714870, by the European Union Seventh Frame-work Programme under grant agreement FP7-PEOPLE-2013-CIG-618229, and the Spanish MINECO under contractMAT2014-53432-C5-5-R and the"María de Maeztu"programfor Units of Excellence in R&D (MDM-2014-0377).

This is the peer reviewed version of the following article: M. Tomás-Gamasa, J. L. Mascareñas, ChemBioChem 2020, 21, 294, which has been published in final form at https://doi.org/10.1002/cbic.201900229. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions ; The conversion of sunlight into chemical energy by using photosynthetic machinery is at the heart of nature and life. Scientists have also learned to use light energy to promote a great variety of chemical reactions, most of which are based on redox processes involving electron‐transfer steps. Indeed, the area of photoredox catalysis has recently emerged as one of the hottest fields in synthetic chemistry. Many of the photoredox reactions discovered so far take place in homogeneous phases, and rely on the use of soluble photoresponsive catalysts. However, in recent years, there have been many advances in the area of heterogeneous photocatalysis, most of which are based on the use of semiconductor materials, such as TiO2, as a key photocatalytic system. These technologies have found different applications, especially in the field of sustainable chemistry and therapy. Herein, some of these applications, and the potential of TiO2‐based photocatalysts in biology and biomedicine, are reviewed ; This work has received financial support from the Spanish Government (SAF2016‐76689‐R, Orfeo‐cinqa network CTQ2016‐81797‐REDC); the Consellería de Cultura, Educación e Ordenación Universitaria (2015‐CP082, ED431C 2017/19); the Centro Singular de Investigación de Galicia accreditation 2016–2019, ED431G/09); the European Union (European Regional Development Fund‐ERDF); and the European Research Council (Advanced Grant No. 340055). M.T.G. thanks the Ministerio de Economía y Competitividad for the Juan de la Cierva‐Incorporación (IJCI‐2015‐23210) ; SI

In the Democratic Republic of the Congo (DRC), medicinal plants represent the main product for both urban and rural populations for their health care needs due to the high costs of conventional medicine. These plant species contain bioactive compounds also called phytochemicals that are capable of modulating metabolic processes and resulting in the promotion of better health. In the present paper, the aims were to give updated infor­mation on the physical properties, phytochemistry and pharmacological activities of L. multiflora, medicinal plant in Republic Democratic of the Congo (DR. Congo). A literature search of this specie was conducted to obtain information about the nutritional value, phytochemistry and biological activities from various electronic databases (PubMed, PubMed Central, Science Direct, Google scholar and Sci-hub). The chemical structures of L. multiflora naturally occurring compounds were drawn using ChemBioDraw Ultra 12.0 software package. In this study, the bibliographic references were using bibliographic software Mendeley. L. multiflora Moldenke is a tropical to subtropical herbaceous aromatic plant widely distributed in West and Central Tropical Africa. It has been traditionally used in ethnomedecine against various disorders. It has been reported that the essential oil composition of L. multiflora from some locations were characterized by high terpenoids content, in particular: 1,8-cineole, linalool, geranial and neral, ipsdienone and (Z)- and (E)-ocimenone, thymol and thymyl acetate, p-cymene, sabinene, α-terpineol, α-phellandrene, myrcene and epoxymyrcene, myrtenol, limonene, (E)- and (Z)-tagetone and ipsenone, nerolidol, geraniol, γ-terpinene, (E)-caryophyllene, and β-farnesene). Many study reported that the plant possess various biological properties like anti-hypotensive, anti-inflammatory, anti-analgesic, anti-pyretic, anti-malaria, anti-oxydant, anti-microbial activities. The present review can therefore help inform future scientific research towards the development of novel drugs of relevance from L. multiflora for the improvement of human health and wellbeing.

This is the peer reviewed version of the following article: M. Lineros-Rosa, M. A. Miranda, V. Lhiaubet-Vallet, Chem. Eur. J. 2020, 26, 7205, which has been published in final form at https://doi.org/10.1002/chem.202000123. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving. ; [EN] Photolabile protecting groups (PPGs) have been exploited in a wide range of chemical and biological applications, due to their ability to provide spatial and temporal control over light-triggered activation. In this work, we explore the concept of a new photocage compound based on the commercial UVA/UVB filter oxybenzone (OB; 2-hydroxy-4-methoxybenzophenone) for photoprotection and controlled release of carbonyl groups. The point here is that oxybenzone not only acts as a mere PPG, but also provides, once released, UV photoprotection to the carbonyl derivative. This design points to a possible therapeutic approach to reduce the severe photoadverse effects of drugs containing a carbonyl chromophore. ; This work was supported by the Spanish Government (project PGC2018-096684-B-I00) and the Universitat Politecnica de Valencia (FPI grant to M.L.-R.). Carmen Clemente Martínez is acknowledged for her technical help during the UPLC-HRMS experiments. ; Lineros-Rosa, M.; Miranda Alonso, MÁ.; Lhiaubet, VL. (2020). A Sunscreen-Based Photocage for Carbonyl Groups. Chemistry - A European Journal. 26(32):7205-7211. https://doi.org/10.1002/chem.202000123 ; S ; 7205 ; 7211 ; 26 ; 32 ; Silva, J. M., Silva, E., & Reis, R. L. (2019). Light-triggered release of photocaged therapeutics - Where are we now? Journal of Controlled Release, 298, 154-176. doi:10.1016/j.jconrel.2019.02.006 ; Klausen, M., Dubois, V., Verlhac, J., & Blanchard‐Desce, M. (2019). Tandem Systems for Two‐Photon Uncaging of Bioactive Molecules. ChemPlusChem, 84(6), 589-598. doi:10.1002/cplu.201900139 ; Brieke, C., Rohrbach, F., Gottschalk, A., Mayer, G., & Heckel, A. (2012). Light‐Controlled Tools. Angewandte ...

Xenobiotic Impacts on the Skeletal System of Teleosts -- Wildlife Exposure to Organophosphorus Insecticides -- Chemical Warfare Agents: Current Status of Oral References Doses -- Diisononyl Phthalate: Chemistry, Environmental Path, and Toxicology -- Photochemistry of Organophosphorus Insecticides.

[EN] Azetidines are interesting compounds in medicine and chemistry as bioactive scaffolds and synthetic intermediates. However, photochemical processes involved in the generation and fate of azetidine-derived radical ions have scarcely been reported. In this context, the photoreduction of this four-membered heterocycle might be relevant in connection with the DNA (6-4) photoproduct obtained from photolyase. Herein, a stable azabipyrimidinic azetidine (AZT(m)), obtained from cycloaddition between thymine and 6-azauracil units, is considered to be an interesting model of the proposed azetidine-like intermediate. Hence, its photoreduction and photo-oxidation are thoroughly investigated through a multifaceted approach, including spectroscopic, analytical, and electrochemical studies, complemented by CASPT2 and DFT calculations. Both injection and removal of an electron result in the formation of radical ions, which evolve towards repaired thymine and azauracil units. Whereas photoreduction energetics are similar to those of the cyclobutane thymine dimers, photo-oxidation is clearly more favorable in the azetidine. Ring opening occurs with relatively low activation barriers ( 13 kcal mol(-1)) and the process is clearly exergonic for photoreduction. In general, a good correlation has been observed between the experimental results and theoretical calculations, which has allowed a synergic understanding of the phenomenon. ; The Spanish Government (CTQ2015-70164-P, CTQ2017-87054-C2-2-P, SVP-2013-068057 grants to A.B.F.-R. and RYC-2015-19234 grant to D.R.-S.) and the Valencia Regional Government (Prometeo/2017/075) are acknowledged for financial support. A.F.-M. is grateful to the Region Grand Est government (France) and the Universite de Lorraine for their financial support. ; Fraga-Timiraos, AB.; Francés-Monerris, A.; Rodríguez Muñiz, GM.; Navarrete-Miguel, M.; Miranda Alonso, MÁ.; Roca Sanjuan, D.; Lhiaubet, VL. (2018). Experimental and Theoretical Study on the Cycloreversion of a Nucleobase-Derived Azetidine by ...

[EN] Photosensitization by drugs is a problem of increasing importance in modern life. This phenomenon occurs when a chemical substance in the skin is exposed to sunlight. Photosensitizing drugs are reported to cause severe skin dermatitis, and indeed, it is generally advised to avoid sunbathing and to apply sunscreen. In this context, the nonsteroidal anti-inflammatory drug (NSAID) diclofenac is a photosensitive drug, especially when administered in topical form. In this work, efforts have been made to design and study an innovative pro-drug/pro-filter system containing diclofenac and the UVA filter avobenzone in order to develop a safer use of this topical drug. The design is based on the presence of a well-established photoremovable phenacyl group in the avobenzone structure. Steady-state photolysis of the dyad in hydrogen-donor solvents, monitored by UV-Vis spectrophotometry and HPLC, confirms the simultaneous photorelease of diclofenac and avobenzone. Laser flash photolysis and phosphorescence emission experiments allow us to gain insight into the photoactive triplet excited-state properties of the dyad. Finally, it is shown that avobenzone provides partial photoprotection to diclofenac from photocyclization to carbazole derivatives. ; The present work was supported by the Spanish Government (CTQ2015-70164-P, BES-2013-066566), Generalitat Valenciana (Prometeo/2017/075). ; Aparici-Espert, MI.; Miranda Alonso, MÁ.; Lhiaubet, VL. (2018). Sunscreen-Based Photocages for Topical Drugs: A Photophysical and Photochemical Study of A Diclofenac-Avobenzone Dyad. Molecules. 23(3):1-11. https://doi.org/10.3390/molecules23030673 ; S ; 1 ; 11 ; 23 ; 3 ; Siegel, R. L., Miller, K. D., & Jemal, A. (2018). Cancer statistics, 2018. CA: A Cancer Journal for Clinicians, 68(1), 7-30. doi:10.3322/caac.21442 ; Curtius, K., Wright, N. A., & Graham, T. A. (2017). An evolutionary perspective on field cancerization. Nature Reviews Cancer, 18(1), 19-32. doi:10.1038/nrc.2017.102 ; Brem, R., Guven, M., & Karran, P. (2017). ...