<?xml version="1.0" encoding="UTF-8"?><?xml-stylesheet type="text/xsl" href="static/style.xsl"?><OAI-PMH xmlns="http://www.openarchives.org/OAI/2.0/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.openarchives.org/OAI/2.0/ http://www.openarchives.org/OAI/2.0/OAI-PMH.xsd"><responseDate>2026-04-27T21:45:21Z</responseDate><request verb="GetRecord" identifier="oai:uvadoc.uva.es:10324/78837" metadataPrefix="dim">https://uvadoc.uva.es/oai/request</request><GetRecord><record><header><identifier>oai:uvadoc.uva.es:10324/78837</identifier><datestamp>2025-10-21T19:03:01Z</datestamp><setSpec>com_10324_38</setSpec><setSpec>col_10324_852</setSpec></header><metadata><dim:dim xmlns:dim="http://www.dspace.org/xmlns/dspace/dim" xmlns:doc="http://www.lyncode.com/xoai" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.dspace.org/xmlns/dspace/dim http://www.dspace.org/schema/dim.xsd">
<dim:field mdschema="dc" element="contributor" qualifier="advisor" lang="es" authority="28e9193279e8604c" confidence="600" orcid_id="0000-0003-1028-779X">López Alonso, Juan Carlos</dim:field>
<dim:field mdschema="dc" element="contributor" qualifier="advisor" lang="es" authority="9f338fc865a2c76f" confidence="600" orcid_id="0000-0002-1196-3844">Blanco Rodríguez, Susana</dim:field>
<dim:field mdschema="dc" element="contributor" qualifier="author" authority="cf4c4da9-f707-4290-ab36-56a09fdb5857" confidence="600" orcid_id="">Colón Jimeno, Alejandro</dim:field>
<dim:field mdschema="dc" element="contributor" qualifier="editor" lang="es" authority="EDUVA45" confidence="600" orcid_id="">Universidad de Valladolid. Facultad de Ciencias</dim:field>
<dim:field mdschema="dc" element="date" qualifier="accessioned">2025-10-21T06:56:44Z</dim:field>
<dim:field mdschema="dc" element="date" qualifier="available">2025-10-21T06:56:44Z</dim:field>
<dim:field mdschema="dc" element="date" qualifier="issued">2024</dim:field>
<dim:field mdschema="dc" element="identifier" qualifier="uri">https://uvadoc.uva.es/handle/10324/78837</dim:field>
<dim:field mdschema="dc" element="description" qualifier="abstract" lang="es">En este Trabajo de Fin de Grado vamos a realizar un estudio teórico de la molécula&#xd;
del N-(1-(2-feniletil)-4-piperidinil)-N-fenil-propanamida o Fentanilo, analizando los&#xd;
diversos confórmeros de la molécula, sus energías y evaluando las interacciones&#xd;
intramoleculares que estabilizan o desestabilizan la molécula. Para la identificación de&#xd;
confórmeros, empleamos el método CREST. Posteriormente, los confórmeros obtenidos&#xd;
fueron optimizados en dos etapas dentro de la aproximación de la teoría del funcional de&#xd;
la densidad (DFT) y el funcional B3LYP incluyendo correcciones empíricas de&#xd;
dispersión.&#xd;
Los 169 confórmeros encontrados se optimizaron a nivel B3LYP/6-31++g(d, p),&#xd;
con los resultados obtenidos se eliminaron los duplicados y se ordenaron por orden de&#xd;
energía. Aquellos con energías relativas ΔE &lt; 500 kJ/mol respecto al confórmero más&#xd;
estable se optimizaron a nivel B3LYP/6-311++g(2d,p) que se redujeron a 12 conformeros&#xd;
incluyendo cálculo de frecuencias para constatar que los conformeros obtenidos son&#xd;
mínimos en la superficie de energía potencial y calcular las propiedades termodinámicas.&#xd;
Para racionalizar porque unos conformeros son más estables que otros se&#xd;
estudiaron las posibles interacciones intramoleculares se realizaron mediante análisis de&#xd;
la teoría cuántica de átomos en moléculas (QTAIM) y de interacciones no covalentes&#xd;
(NCI). Para finalizar contrastamos los datos obtenidos con datos experimentales&#xd;
publicados con anterioridad.</dim:field>
<dim:field mdschema="dc" element="description" qualifier="abstract" lang="es">In this Final Degree Project, we will conduct a theoretical study of the molecule&#xd;
N-(1-(2-phenylethyl)-4-piperidinyl)-N-phenyl-propanamide, or Fentanyl, analyzing the&#xd;
various conformers of the molecule, their energies, and evaluating the intramolecular&#xd;
interactions that stabilize or destabilize the molecule. To identify conformers, we&#xd;
employed the CREST method. Subsequently, the obtained conformers were optimized&#xd;
in two stages within the framework of density functional theory (DFT) using the&#xd;
B3LYP functional with empirical dispersion corrections.&#xd;
The 169 conformers found were optimized at the B3LYP/6-31++g(d,p) level,&#xd;
and based on the results, duplicates were removed, and the conformers were ranked by&#xd;
energy. Those with relative energies ΔE &lt; 500 kJ/mol compared to the most stable&#xd;
conformer were further optimized at the B3LYP/6-311++g(2d,p) level, resulting in 12&#xd;
conformers. Frequency calculations were performed to confirm that the conformers are&#xd;
minima on the potential energy surface and to calculate their thermodynamic properties.&#xd;
To understand why some conformers are more stable than others, possible&#xd;
intramolecular interactions were studied through analyses based on Quantum Theory of&#xd;
Atoms in Molecules (QTAIM) and Non-Covalent Interaction (NCI) methods. Finally,&#xd;
we compared the obtained data with previously published experimental data.</dim:field>
<dim:field mdschema="dc" element="description" qualifier="sponsorship" lang="es">Departamento de Química Física y Química Inorgánica</dim:field>
<dim:field mdschema="dc" element="description" qualifier="degree" lang="es">Grado en Química</dim:field>
<dim:field mdschema="dc" element="format" qualifier="mimetype" lang="es">application/pdf</dim:field>
<dim:field mdschema="dc" element="language" qualifier="iso" lang="es">spa</dim:field>
<dim:field mdschema="dc" element="rights" qualifier="accessRights" lang="es">info:eu-repo/semantics/openAccess</dim:field>
<dim:field mdschema="dc" element="rights" qualifier="uri" lang="*">http://creativecommons.org/licenses/by-nc-nd/4.0/</dim:field>
<dim:field mdschema="dc" element="rights" lang="*">Attribution-NonCommercial-NoDerivatives 4.0 Internacional</dim:field>
<dim:field mdschema="dc" element="subject" qualifier="classification" lang="es">Fentanilo</dim:field>
<dim:field mdschema="dc" element="subject" qualifier="classification" lang="es">Método CREST</dim:field>
<dim:field mdschema="dc" element="subject" qualifier="classification" lang="es">QTAIM</dim:field>
<dim:field mdschema="dc" element="title" lang="es">Conformación y estructura de moléculas de interés biológico: el fentanilo</dim:field>
<dim:field mdschema="dc" element="type" lang="es">info:eu-repo/semantics/bachelorThesis</dim:field>
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