Design, Synthesis, Photochemical and Biological Evaluation of Novel Photoactive Molecular Switches

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Design, Synthesis, Photochemical and Biological Evaluation of Novel Photoactive Molecular Switches TESIS DOCTORAL Título Design, Synthesis, Photochemical and Biological Evaluation of Novel Photoactive Molecular Switches Autor/es David Martínez López Director/es Diego Sampedro Ruiz y Pedro José Campos García Facultad Facultad de Ciencia y Tecnología Titulación Departamento Química Curso Académico Design, Synthesis, Photochemical and Biological Evaluation of Novel Photoactive Molecular Switches, tesis doctoral de David Martínez López, dirigida por Diego Sampedro Ruiz y Pedro José Campos García (publicada por la Universidad de La Rioja), se difunde bajo una Licencia Creative Commons Reconocimiento-NoComercial- SinObraDerivada 3.0 Unported. ̉ Permisos que vayan más allá de lo cubierto por esta licencia pueden solicitarse a los titulares del copyright. © El autor © Universidad de La Rioja, Servicio de Publicaciones, 2019 publicaciones.unirioja.es E-mail: [email protected] Facultad de Ciencia y Tecnología Departamento de Química Área de Química Orgánica Grupo de Fotoquímica Orgánica TESIS DOCTORAL DESIGN, SYNTHESIS, PHOTOCHEMICAL AND BIOLOGICAL EVALUATION OF NOVEL PHOTOACTIVE MOLECULAR SWITCHES Memoria presentada en la Universidad de La Rioja para optar al grado de Doctor en Química por: David Martínez López Junio 2019 Facultad de Ciencia y Tecnología Departamento de Química Área de Química Orgánica Grupo de Fotoquímica Orgánica D. DIEGO SAMPEDRO RUIZ, Profesor Titular de Química Orgánica del Departamento de Química de la Universidad de La Rioja, y D. PEDRO JOSÉ CAMPOS GARCÍA, Catedrático de Química Orgánica del Departamento de Química de la Universidad de La Rioja. CERTIFICAN: Que la presente memoria, titulada “Design, synthesis, photochemical and biological evaluation of novel photoactive molecular switches”, ha sido realizada en el Departamento de Química de La Universidad de La Rioja bajo su dirección por el Licenciado en Química D. DAVID MARTÍNEZ LÓPEZ y autorizan su presentación para que sea calificada como Tesis Doctoral. Logroño, Junio de 2019 Fdo. Diego Sampedro Ruiz Fdo. Pedro J. Campos García Agradecimientos Finalmente una etapa acaba, en la que hace unos años ni me imaginaba que pudiera ni siquiera empezar. Por ello, en primer lugar me gustaría agradecer a mis directores de tesis, Diego y Pedro por haberme dado una gran acogida en el grupo de investigación desde el principio, así como por el apoyo que me han brindado en los buenos y malos momentos, además del esfuerzo que han aportado para la realización de esta memoria. A Miguel Ángel, además de uno de mis jefes, un amigo más con el que he compartido alegrías, penas y alguna que otra cerveza… Por todo ello, una persona imprescindible que la tesis ha puesto en mi vida y de la cual quiero seguir aprendiendo por mucho tiempo. De la misma manera, para que una tesis sea más fácil de llevar, es imprescindible que en este largo camino se tengan tan buenos compañeros de laboratorio como los míos. En este caso, agradecer a Raúl tanto por los buenos momentos, como por el apoyo técnico siempre que he necesitado. A Elena y Eduardo por hacerme más ameno el día a día, sobre todo en los que lo veía todo negro y siempre al final, me sacaban una sonrisa. También agradecer a Cris (mi calculadora), sin la que hubiera sido imposible realizar esta tesis doctoral, pero reconocerle sobre todo su amabilidad en todo momento. Tampoco me quiero olvidar de los antiguos compañeros, en especial de Marina ya que fue la que me enseñó a desenvolverme en el laboratorio, aunque el primer día la mojé entera. Qué decir de los quibi-buitres, gracias a todos ellos (Iris A., Ismael, Xhenti, Paula, Malicia, Pablo, Claudio y Nuria) por los ratos divertidos en el laboratorio, y sobre todo por los viernes de pinchopote. A pesar de estar en el otro lado de la química, también he tenido buenos compañeros inorgánicos (Mattia, María G., María R., Quinti, Mónica, Raquel, Patri, Manso y Jesús) gracias a todos ellos por los jueves de “Impass” que hemos pasado juntos. No me puedo olvidar de ninguna manera del PAS, en especial de Nines por todas las conversaciones y risas que hemos tenido en el masas durante tantos años. También agradecer a todos mis amigos por hacerme siempre desconectar, y a la vez interesarse por mis experimentos. Dedicar también un agradecimiento especial a Patri por realizar la portada de esta Tesis Doctoral. I am really grateful to Prof. Andrew Woolley for allowing me be part of his lab team for 4 months. He provided me all the support needed to carry out my research work. Agradecimientos Moreover, I would like to flag his kindness at all times with any member of his group, creating an excellent working atmosphere. Also, I would like to thank Debbie and June for checking the grammar of this thesis. Aparte de toda la gente que he conocido durante la realización de este trabajo, debo de agradecer a mis padres y mi hermana por todo el apoyo, ánimo y cariño que me han dado durante tantos años (no solo los de la tesis) siendo imprescindibles y necesarios para convertirme en la persona que soy hoy en día. Por último y no menos importante, agradecer a Nora por estar todos los días a mi lado compartiendo este camino que iniciamos ya hace unos cuantos años juntos. No se me ocurre mejor compañera para compartir mi vida. En último lugar, agradecer a las entidades financiadores por el apoyo económico prestado para la realización de este trabajo. En especial, me gustaría agradecer a la Universidad de La Rioja por el contrato predoctoral FPI-UR y las ayudas a tesis doctorales (ATUR), así como al Ministerio de Ciencia e Innovación por los proyectos CTQ2011-24800, CTQ2014-59650-P y CTQ2017-87372-P. Table of contents ABSTRACT 1 RESUMEN 3 NOMENCLATURE 5 INTRODUCTION 11 1. Brief history of photochemistry. 13 2. Physical basis. 16 2.1. Electromagnetic radiation. 16 2.2. Franck-Condon principle. 17 2.2.1. Nature of electronic transitions in organic compounds. 18 2.3. Excitation pathways. 18 2.3.1. Direct irradiation. 18 2.3.2. Indirect irradiation. 19 2.3.2.1. Energy transfer photosensitization. 19 2.4. Relaxation decay. 20 2.4.1. Photophysical processes. 21 2.4.2. Photochemical processes. 22 LITERATURE REVIEW 25 1. Molecular machines. 27 1.1. Molecular switches. 28 1.2. How to activate a molecular switch. 28 1.2.1. Electrochemical switches. 28 1.2.2. Chemical switches. 29 1.2.3. Photoswitches. 30 1.2.3.1. Advantages of light. 30 2. Using light as a source of energy in biological applications. 32 2.1. Photodynamic therapy (PDT). 32 2.2. Optogenetics. 35 2.3. Photoremovable protecting groups. 37 3. Types of molecular switches activated by light. 39 3.1. E/Z isomerization based molecular switches. 39 3.1.1. Protonated Schiff base (PSB) of the retinal. 40 3.1.1.1. Indanylidene-pyrrolines (IP). 41 3.1.1.2. Fluorenylidene-pyrrolines (FP). 42 3.1.1.3. Dibenzylidene-pyrrolines. 43 Table of contents 3.1.2. Green Fluorescent protein (GFP) chromophore. 44 3.1.3. Phytochromes. 48 3.1.4. Overcrowded alkenes. 49 3.1.5. Azobenzenes. 52 3.2. Ring opening/closing photoswitches. 56 3.2.1. Diarylethenes. 56 3.2.2. Spiropyrans. 58 3.2.3. Donor acceptor Stenhouse adducts (DASAs). 60 4. Applications. 65 4.1. Photoswitchable peptides. 65 4.1.1. Photoresponsive switches into the backbone peptide. 65 4.2.1. Cross-linked peptides. 66 4.2. Photopharmacology. 68 4.2.1. Aspects to design an efficient photoswitchable drug. 70 4.2.2. Photoswitchable moieties applied in photopharmacology. 71 4.2.2.1. Photocontrol of antibacterial properties. 72 4.2.2.2. Photocontrol of cytotoxic activity. 73 4.2.2.3. Photoswitches for ion channels. 74 OBJECTIVES 77 HYDANTOIN-BASED MOLECULAR SWITCHES 81 1. Synthesis of hydantoin-based molecular switches. 85 2. Photochemical study. 88 2.1. Absorption and emission properties. 88 2.2. Nature of the electronic excited state. 93 2.3. Photoisomerization. 94 2.3.1. Irradiation of photoswitches using a 125-W medium-pressure Hg lamp. 95 2.3.2. Irradiation of photoswitches using a photoreactor. 101 2.3.3. Irradiation of photoswitches using monochromatic light. 102 2.4. Isomerization Quantum yield. 107 2.5. Thermal and photochemical stability 108 3. Computational study. 112 4. Experimental data. 117 4.1. General synthesis of photoswitches. 117 4.2. Characterization data. 119 Table of contents RHODOPSIN-BASED MOLECULAR SWITCHES 127 1. Design of new photoswitches based on the PSB-retinal. 131 2. Synthesis of molecular switches based on the PSB-retinal. 135 3. Photochemical study. 139 3.1. Photophysical properties of novel quaternized molecular switches based on the PSB-retinal. 139 3.2. Irradiation of photoswitches. 143 3.2.1. Photoswitching by direct irradiation. 144 3.2.2. Sensitization processes. 146 3.2.2.1. Photoswitching through triplet state. 146 3.2.2.2. Laser flash photolysis studies. 152 3.3. Thermal back reversion. 159 4. Applications. 161 4.1. Molecular Solar thermal system (MOST). 161 4.2. Modification of a peptide conformation. 162 4.2.1. Photochemical study of the cross-linked peptide. 165 4.2.2. Biological study. 168 5. Experimental data. 171 5.1. Characterization data. 177 METRONIDAZOLE-BASED MOLECULAR SWITCHES 181 1. Design of new photoswitches based on metronidazole moiety. 188 2. Synthesis of metronidazole-like photoswitches. 190 3. Photochemical and photophysical studies. 193 3.1 Absorption wavelength. 193 3.1.1. Computational calculations. 196 3.2. Irradiation of molecular switches based on metronidazole. 201 3.2.1. Computational calculations. 204 3.2.2. Isomerization quantum yield of E-24a. 207 3.2.3. Thermal back reversion. 208 3.2.4. Stability of E-24a. 208 4. Biological study. 210 5. Experimental data. 216 5.1.
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