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Author Correction: Relative configuration of micrograms of natural compounds using proton residual chemical shift anisotropy
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Productos naturales bioactivos de organismos marinos de la Península de Yucatán, México
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Esta tesis doctoral describe la primera investigación exhaustiva sobre los productos naturales marinos de organismos recolectados a lo largo de las costas de la Península de Yucatán, México. Se recolectaron un total de 65 organismos que corresponden a 55 especies diferentes de las cuales 41 son esponjas, 13 ascidias y 1 gorgonia. Se utilizó la estrategia de aislamiento bioguiado y técnicas de desreplicación, mediante las cuales pudimos obtener 31 moléculas, de las que 10 resultaron ser nuevos compuestos naturales, mostrando algunos de ellos interesantes actividades biológicas. Cabe destacar que para la determinación estructural de algunos de los nuevos compuestos se han empleado por primera vez la aplicación de dos nuevas metodologías para la determinación de la configuración relativa de productos naturales marinos: la anisotropía de desplazamiento químico de protón (1H RCSA) y la utilización del análisis configuracional de RMN basado en J dependiente de la temperatura y en cambios de disolvente.
Capítulo 1. Se hace una recopilación de las publicaciones que recogen las investigaciones en el área de los productos naturales marinos de la península de Yucatán hasta mediados del año 2019. Esta revisión bibliográfica dio origen a una publicación en la revista Marine Drugs (Mar. Drugs. 2020, 18, 59).
Capítulo 2. Se describe la recolección de 65 organismos marinos en las costas de la Península de Yucatán, Mexico y su posterior extracción para así obtener los correspondientes extractos orgánicos. A continuación, se presentan los resultados de las actividades antibacteriana, antivírica y antiproliferativa de todos los extractos obtenidos. El fraccionamiento biodirigido de uno de los extractos marinos permitió aislar e identificar los compuestos causantes de la actividad antibacteriana para la esponja Amphimedon compressa.
Capítulo 3. Se describe el aislamiento, la determinación estructural y la evaluación farmacológica de los compuestos puros obtenidos de las esponjas Spongia tubulifera, Ircinia felix, Agelas dilatata y la gorgonia Briareum asbestinum, organismos colectados en las costas de la Península de Yucatán, México. La elucidación estructural de las moléculas se realizó a partir de la utilización de ténicas espectroscópicas de RMN, UV e IR y espectrométricas (MS), mientras que la configuración absoluta se obtuvo a partir de cálculos computacionales (DFT), dicroísmo circular electrónico (ECD) y rayos X. Tres de los compuestos aislados de S. tubulifera mostraron una actividad citotóxica frente a líneas celulares de cáncer, otros dos aislados de I. felix presentaron una actividad antivírica muy potente frente a dos tipos de virus y finalmente dos de los metabolitos secundarios aislados de A. dilatata revelaron actividad frente a dos cepas bacterianas multiresistentes.
Capítulo 4. Se expone la aplicación de dos nuevas metodologías para la determinación de la configuración relativa de dos nuevos productos naturales marinos: a) el uso del RMN de protón anisotrópico (1H RCSA) para obtener la configuración relativa del briarano B-3 a escala de microgramos de muestra y la aplicación del análisis configuracional de RMN basado en J dependiente de la temperatura y en cambios de disolvente, para determinar la configuración relativa de la nocardiomicina.[Resumo]
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.[Abstract]
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
Obtención de compuestos bioactivos presentes en las glándulas salivales posteriores del pulpo octopus maya /
No full textRelative Configuration of Micrograms of Natural Compounds Using Proton Residual Chemical Shift Anisotropy
Full text link[Abstract] 3D molecular structure determination is a challenge for organic compounds or natural products available in minute amounts. Proton/proton and proton/carbon correlations yield the constitution. J couplings and NOEs oftentimes supported by one-bond 1H,13C residual dipolar couplings (RDCs) or by 13C residual chemical shift anisotropies (RCSAs) provide the relative configuration. However, these RDCs or carbon RCSAs rely on 1% natural abundance of 13C preventing their use for compounds available only in quantities of a few 10’s of µgs. By contrast, 1H RCSAs provide similar information on spatial orientation of structural moieties within a molecule, while using the abundant 1H spin. Herein, 1H RCSAs are accurately measured using constrained aligning gels or liquid crystals and applied to the 3D structural determination of molecules with varying complexities. Even more, deuterated alignment media allow the elucidation of the relative configuration of around 35 µg of a briarane compound isolated from Briareum asbestinum.This work was supported by the Max Planck Society and grew out of a collaboration in the context of the Forschergruppe (FOR 934) continued now by the DFG (Gr1211/19–1 and Re1007/9–1)/CAPES 418729698 project. N.N. gratefully acknowledges the financial support by SERB, New Delhi for ECR Grant with File No.: ECR/2017/001811. This work was also funded by grants RTI2018-093634-B-C22 from the State Agency for Research (AEI) of Spain, both co-funded by the FEDER Programme from the European Union, BLUEBIOLAB (0474_BLUEBIOLAB_1_E), Programme INTERREG V A of Spain-Portugal (POCTEP) and GRC2018/039 and Agrupación Estratégica CICA-INIBIC ED431E 2018/03 from Xunta de Galicia. C.J., J.R., and D.P.P. acknowledge CESGA for the computational support. J.C.F. acknowledges predoctoral research stay grant Inditex-UDC. D.P.P. received a fellowship from the program National Council of Science and Technology (CONACYT) of Mexico and the Secretariat of Research, Innovation and Higher Education (SIIES) of Yucatan (Mexico). We also thank Dr. G. Jithender Reddy for one isotropic measurement. We also thank Dr. Christian Schmidt for his cooperation in the manufacturing of micro stretching device. ANV thanks CNPq for a research fellowship and financial support M(426216/2018–0)German Research Foundation; Gr1211/19–1German Research Foundation; Re1007/9–1Brasil. Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES); 418729698República de la India. Science and Engineering Research Board; ECR/2017/001811Xunta de Galicia; 0474_BLUEBIOLAB_1_EXunta de Galicia; GRC2018/039Xunta de Galicia; ED431E 2018/03Brasil. Conselho Nacional de Desenvolvimento Científico e Tecnológico; M(426216/2018–0
Antimicrobial Diterpene Alkaloids from an Agelas citrina Sponge Collected in the Yucatán Peninsula
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