[en] This doctoral thesis describes the first exhaustive research on marine natural products from organisms collected along the coasts of the Yucatan Peninsula, Mexico. A total of 65 organisms were collected that correspond to 55 different species of which 41 are sponges, 13 ascidians and 1 gorgonian. The bioguided isolation strategy and dereplication techniques were used, through which we were able to obtain 31 molecules, of which 10 were found to be new natural compounds, showing some of them interesting biological activities. It should be noted that for the structural determination of some of the new compounds, the application of two new methodologies for the determination of the relative configuration of marine natural products has been used for the first time: the proton chemical shift anisotropy (1H RCSA) and the use of variable temperature and solvent dependent NMR J-based configurational analysis. Chapter 1. A compilation is made of the publications that collect the research in the area of marine natural products of the Yucatan Peninsula until the middle of the year 2019. This bibliographic review gave rise to a publication in the journal Marine Drugs (Mar. Drugs. 2020, 18, 59). Chapter 2. The collection of 65 marine organisms on the coasts of the Yucatan Peninsula, Mexico and their subsequent extraction is described in order to obtain the corresponding organic extracts. The results of the antibacterial, antiviral and antiproliferative activities of all the extracts obtained are presented below. The biodirected fractionation of one of the marine extracts allowed to isolate and identify the compounds that cause antibacterial activity for the Amphimedon compresssa sponge. Chapter 3. The isolation, structural determination and pharmacological evaluation of the pure compounds obtained from sponges Spongia tubulifera, Ircinia felix, Agelas dilatata and gorgonian Briareum asbestinum, organisms collected on the coasts of the Yucatan Peninsula, Mexico, are described. The structural elucidation of the molecules was made from the use of NMR, UV and IR and spectrometric (MS) spectroscopic techniques, while the absolute configuration was obtained from computational calculations (DFT), electronic circular dichroism (ECD) and X-rays. Three of the compounds isolated of S. tubulifera showed a cytotoxic activity against cancer cell lines, two other compounds isolated of I. felix showed a very potent antiviral activity against two types of viruses and finally two of the secondary metabolites isolated of A. dilatata revealed activity against two multiresistant bacterial strains. Chapter 4. The application of two new methodologies for the determination of the relative configuration of two new marine natural products is presented: a) the use of anisotropic proton NMR (1H RCSA) to obtain the relative configuration of the briarane B-3 in scale of micrograms of sample and the application of the variable temperature and solvent dependent NMR J-based configurational analysis to determine the relative configuration of nocardiomycin.

[gl] Esta tese doutoral describe a primeira investigación exhaustiva sobre produtos naturais mariños procedentes de organismos recollidos ao longo das costas da Península de Yucatán, México. Recolléronse un total de 65 organismos, correspondentes a 55 especies diferentes, das cales 41 son esponxas, 13 ascites e 1 gorgonia. Utilizáronse a estratexia de illamento bioguido e as técnicas de eliminación, a través das cales conseguimos obter 31 moléculas, das cales 10 atopáronse novos compostos naturais, mostrando algunhas interesantes actividades biolóxicas. Cómpre salientar que para a determinación estrutural dalgúns dos novos compostos, a aplicación de dúas novas metodoloxías para a determinación da configuración relativa dos produtos naturais mariños utilizouse por primeira vez: a anisotropía de desprazamento químico de protóns (1H RCSA) e a uso da análise configuracional baseada en J de cambios dependentes de temperatura e solventes. Capítulo 1. Faise unha recompilación das publicacións que recollen a investigación na área de produtos naturais mariños da Península de Yucatán ata mediados do ano 2019. Esta revisión bibliográfica deu lugar a unha publicación na revista Marine Drugs (Mar. Drugs. 2020, 18, 59). Capítulo 2. Descríbese a colección de 65 organismos mariños nas costas da península de Yucatán, México e a súa posterior extracción para obter os correspondentes extractos orgánicos. A continuación móstranse os resultados das actividades antibacterianas, antivirais e antiproliferativas de todos os extractos obtidos. O fraccionamento biodireccionado dun dos extractos mariños permitiu illar e identificar os compostos que causan actividade antibacteriana para a esponxa Amphimedon compresssa. Capítulo 3. Descríbense o illamento, determinación estrutural e avaliación farmacolóxica dos compostos puros obtidos de esponxas Spongia tubulifera, Ircinia felix, Agelas dilatata e gorgonia Briareum asbestinum, organismos recollidos nas costas da península de Yucatán, México. A elucidación estrutural das moléculas fíxose a partir do uso de técnicas espectroscópicas RMN, UV e IR e espectrometría (MS), mentres que a configuración absoluta obtívose a partir de cálculos computacionais (DFT), dicroísmo electrónico electrónico (ECD) e raios X. Tres dos compostos illados de S. tubulifera mostraron unha actividade citotóxica contra as liñas celulares do cancro, outros dous illados de I. felix mostraron unha actividade antiviral moi potente contra dous tipos de virus e finalmente dous dos metabolitos secundarios. Os illados de A. dilatata revelaron actividade contra dúas cepas bacterianas multirresistentes. Capítulo 4. Preséntase a aplicación de dúas novas metodoloxías para a determinación da configuración relativa de dous novos produtos naturais mariños: a) o uso de protóns anisotrópicos RMN (1H RCSA) para obter a configuración relativa da escala de briarano B-3 de microgramos de mostra e a aplicación de análises configuracional de RMN baseada en J dependente da temperatura e cambios de disolventes para determinar a configuración relativa da nocardiomicina.