<rdf:RDF xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#" xmlns:dcterms="http://purl.org/dc/terms/">
<rdf:Description rdf:about="https://riquim.fq.edu.uy/items/show/6966">
    <dcterms:title><![CDATA[<strong>Chromene flavanones from Dalea boliviana as xanthine oxidase inhibitors : in vitro biological evaluation and molecular docking studies</strong>]]></dcterms:title>
    <dcterms:subject><![CDATA[FLAVONOIDES]]></dcterms:subject>
    <dcterms:subject><![CDATA[CROMEO]]></dcterms:subject>
    <dcterms:subject><![CDATA[XANTINA OXIDASA]]></dcterms:subject>
    <dcterms:subject><![CDATA[INHIBICION]]></dcterms:subject>
    <dcterms:subject><![CDATA[HIPERURICEMIA]]></dcterms:subject>
    <dcterms:subject><![CDATA[DALEA BOLIVIANA]]></dcterms:subject>
    <dcterms:subject><![CDATA[ACOPLAMIENTO MOLECULAR]]></dcterms:subject>
    <dcterms:subject><![CDATA[SABOR]]></dcterms:subject>
    <dcterms:subject><![CDATA[BIBLIOGRAFIA NACIONAL QUIMICA]]></dcterms:subject>
    <dcterms:subject><![CDATA[2025]]></dcterms:subject>
    <dcterms:abstract><![CDATA[Background: Prenylated flavanones represent a structurally diverse class of natural compounds with significant biological potential. Among them, chromene flavanones (CFs) constitute a rare and specialized subgroup with promising therapeutic applications. These molecules have gained attention due to their potential to inhibit xanthine oxidase (XO), a key enzyme involved in oxidative stress-related disorders such as gout and hyperuricemia. Their distinctive structural features, combined with notable bioactivity, make them compelling candidates for further pharmacological exploration. Given their potential relevance, this study focuses on the in vitro and in silico evaluation of three CFs isolated from Dalea boliviana Britton [Fabacea], assessing their capacity to inhibit XO and elucidating key structure–activity relationships (SARs) that contribute to their biological effectiveness. Purpose: This study aims to investigate the in vitro and in silico interactions of the chromene flavanones, namely, (2S) 5,2′-dihydroxy-6″,6″-dimethylchromeno- (7,8:2″,3″)-flavanone (1), (2S) 5,2′-dihydroxy-6″,6″-dimethylchromeno-(7,8: 2″,3″)-3′-prenylflavanone (2), and obovatin (3), obtained from D. boliviana, with XO, in order to explore their potential as XO inhibitors and their potential therapeutic applications for hyperuricemic diseases. Material and Methods: XO inhibition by the three chromene flavanones was measured spectroscopically. The relationships between their structures and inhibitory activities were evaluated. Moreover, molecular docking studies were performed to propose the binding modes of the most active natural compounds. Results and discussion: Compounds 1 and 2 exhibited potent inhibition, with IC50 values in the nanomolar range (0.5 ± 0.01 nM and 1.7 ± 0.46 nM, respectively), demonstrating significantly higher activity than allopurinol (AL), the reference inhibitor (IC50 = 247 ± 4 nM). In contrast, compound 3 displayed only weak inhibition. SAR analysis revealed that the presence of a chromene moiety in the A-ring, combined with hydroxyl and prenyl groups in the B-ring, played a crucial role in enhancing inhibitory activity. Molecular docking studies confirmed the strong binding affinities of compounds 1 and 2 within the active site of XO (PDB ID: 3NVY), with binding energies of −6.1687 kcal/mol and −6.7820 kcal/mol, respectively. Key stabilizing interactions involved π–π interactions with Phe914 and hydrogen bonding with residues such as Leu873 and Leu1014. These findings highlight the structural features essential for potent XO inhibition and suggest that chromene flavanones represent a valuable scaffold for the development of novel inhibitors. Further molecular dynamics simulations could provide deeper insights into their stability and interaction dynamics, aiding in the rational design of more effective XO inhibitors. Conclusion: Our findings lead us to propose these chromene flavanones as lead compounds for the design and development of novel XO inhibitors for treating diseases in which exacerbated activity of this enzyme is involved.]]></dcterms:abstract>
    <dcterms:creator><![CDATA[<strong>Bedoya Aguirre, Einy Nallybe</strong>]]></dcterms:creator>
    <dcterms:creator><![CDATA[<strong>Santi, María Daniela</strong>]]></dcterms:creator>
    <dcterms:creator><![CDATA[<strong>Negro, Melisa Fabiana</strong>]]></dcterms:creator>
    <dcterms:creator><![CDATA[<strong>Echeverría, Javier</strong>]]></dcterms:creator>
    <dcterms:creator><![CDATA[<strong>Paulino Zunini, Margot</strong>]]></dcterms:creator>
    <dcterms:creator><![CDATA[<strong>Peralta, Mariana Andrea</strong>]]></dcterms:creator>
    <dcterms:creator><![CDATA[<strong>Ortega, María Gabriela</strong>]]></dcterms:creator>
    <dcterms:source><![CDATA[Frontiers in Pharmacology, v. 16, 2025. -- art. no. 1576390]]></dcterms:source>
    <dcterms:publisher><![CDATA[Frontiers]]></dcterms:publisher>
    <dcterms:date><![CDATA[2025]]></dcterms:date>
    <dcterms:rights><![CDATA[<p><strong>Información sobre Derechos de Autor</strong></p>
<p>(Por favor lea este aviso antes de abrir los documentos u objetos)</p>
<p><strong>La legislación uruguaya protege el derecho</strong> de autor sobre toda creación literaria, científica o artística, tanto en lo que tiene que ver con sus derechos morales, como en lo referente a los derechos patrimoniales con sujeción a lo establecido por el derecho común y las siguientes leyes (LEY 9.739 DE 17 DE DICIEMBRE DE 1937 SOBRE PROPIEDAD LITERARIA Y ARTISTICA CON LAS MODIFICACIONES INTRODUCIDAS POR LA LEY DE DERECHO DE AUTOR Y DERECHOS CONEXOS No. 17.616 DE 10 DE ENERO DE 2003, LEY 17.805 DE 26 DE AGOSTO DE 2004, LEY 18.046 DE 24 DE OCTUBRE DE 2006 LEY 18.046 DE 24 DE OCTUBRE DE 2006)</p>
<p><strong>ADVERTENCIA -</strong> La consulta de este documento queda condicionada a la aceptación de las siguientes condiciones de uso: Este documento es únicamente para usos privados enmarcados en actividades de investigación y docencia. No se autoriza su reproducción con fines de lucro. Esta reserva de derechos afecta tanto los datos del documento como a sus contenidos. En la utilización o cita de partes debe indicarse el nombre de la persona autora.</p>]]></dcterms:rights>
    <dcterms:format><![CDATA[PDF]]></dcterms:format>
    <dcterms:extent><![CDATA[9 p.]]></dcterms:extent>
    <dcterms:language><![CDATA[Inglés]]></dcterms:language>
    <dcterms:type><![CDATA[Artículo]]></dcterms:type>
    <dcterms:identifier><![CDATA[10.3389/fphar.2025.1576390]]></dcterms:identifier>
</rdf:Description><rdf:Description rdf:about="https://riquim.fq.edu.uy/items/show/6732">
    <dcterms:title><![CDATA[<strong>Prenylated flavonoids from Dalea genus as xanthine oxidase inhibitors: in vitro bioactivity evaluation and molecular docking studies</strong>]]></dcterms:title>
    <dcterms:subject><![CDATA[FLAVONOIDES]]></dcterms:subject>
    <dcterms:subject><![CDATA[XANTINA OXIDASA]]></dcterms:subject>
    <dcterms:subject><![CDATA[ACOPLAMIENTO MOLECULAR]]></dcterms:subject>
    <dcterms:subject><![CDATA[HIPERURICEMIA]]></dcterms:subject>
    <dcterms:subject><![CDATA[BIBLIOGRAFIA NACIONAL QUIMICA]]></dcterms:subject>
    <dcterms:subject><![CDATA[2023]]></dcterms:subject>
    <dcterms:abstract><![CDATA[Prenylated flavanones are a family of compounds with an important biological potential. Previously, anti tyrosinase activity, acetylcholinesterase inhibitory activity, and neuroprotective effects of several prenyl flava nones isolated from different American Dalea genus species were reported. The biological potency of these kinds of compounds, together with the particularity of their chemical structures, encouraged us to investigate them for in vitro and in silico anti-xanthine oxidase activity. So, five prenyl-flavanones obtained from different Dalea sp (Dalea elegans, Dalea boliviana, and Dalea pazensis) were studied and the relationships between the structure of these prenyl-flavanones and their inhibitory activity were evaluated. Molecular docking studies were performed in order to propose the binding mode of the most active natural compound. 2&prime;,4&prime;-dihydroxy-5&prime;-(1‴,1‴-dimethy lallyl)-8-prenylpinocembrin (1) was the most active in this series showing an IC50 of 0.26 &plusmn; 0.07 &micro;M comparable with the reference inhibitor, allopurinol. The presence of 5,7,2&prime;,4&prime;-tetrahydroxy substitution, accompanied by a prenyl group at 8-position in the A-ring, and a 5&prime; (1‴,1‴-dimethylallyl) were important to present a xanthine oxidase inhibitory activity. This fact was confirmed with molecular docking studies showing relevant interactions of 1 with the residues of the catalytic site of xanthine oxidase, and a binding energy of &minus; 7.3297 kcal mol&minus; 1 . These results contributed not only to understanding the binding mode but also to validating the in vitro results. The obtained findings lead us to propose these prenyl-flavanones as lead compounds for the design and devel opment of novel xanthine oxidase inhibitors for the treatment of diseases in which this enzyme is involved.]]></dcterms:abstract>
    <dcterms:creator><![CDATA[<strong>Santi, M.D.</strong>]]></dcterms:creator>
    <dcterms:creator><![CDATA[<strong>Bedoya Aguirre, E.</strong>]]></dcterms:creator>
    <dcterms:creator><![CDATA[<strong>Negro, M.F.</strong>]]></dcterms:creator>
    <dcterms:creator><![CDATA[<strong>Zunini, M. Paulino</strong>]]></dcterms:creator>
    <dcterms:creator><![CDATA[<strong>Peralta, M.A.</strong>]]></dcterms:creator>
    <dcterms:creator><![CDATA[<strong>Ortega, M. G.</strong>]]></dcterms:creator>
    <dcterms:source><![CDATA[Results in Chemistry v.6, 2023. -- e101115]]></dcterms:source>
    <dcterms:publisher><![CDATA[Elsevier]]></dcterms:publisher>
    <dcterms:date><![CDATA[2023]]></dcterms:date>
    <dcterms:rights><![CDATA[<p><strong>Informaci&oacute;n sobre Derechos de Autor</strong></p>
<p>(Por favor lea este aviso antes de abrir los documentos u objetos)</p>
<p><strong>La legislaci&oacute;n uruguaya protege el derecho</strong>&nbsp;de autor sobre toda creaci&oacute;n literaria, cient&iacute;fica o art&iacute;stica, tanto en lo que tiene que ver con sus derechos morales, como en lo referente a los derechos patrimoniales con sujeci&oacute;n a lo establecido por el derecho com&uacute;n y las siguientes leyes (LEY 9.739 DE 17 DE DICIEMBRE DE 1937 SOBRE PROPIEDAD LITERARIA Y ARTISTICA CON LAS MODIFICACIONES INTRODUCIDAS POR LA LEY DE DERECHO DE AUTOR Y DERECHOS CONEXOS No. 17.616 DE 10 DE ENERO DE 2003, LEY 17.805 DE 26 DE AGOSTO DE 2004, LEY 18.046 DE 24 DE OCTUBRE DE 2006 LEY 18.046 DE 24 DE OCTUBRE DE 2006)</p>
<p><strong>ADVERTENCIA -</strong>&nbsp;La consulta de este documento queda condicionada a la aceptaci&oacute;n de las siguientes condiciones de uso: Este documento es &uacute;nicamente para usos privados enmarcados en actividades de investigaci&oacute;n y docencia. No se autoriza su reproducci&oacute;n con fines de lucro. Esta reserva de derechos afecta tanto los datos del documento como a sus contenidos. En la utilizaci&oacute;n o cita de partes debe indicarse el nombre de la persona autora.</p>]]></dcterms:rights>
    <dcterms:format><![CDATA[PDF]]></dcterms:format>
    <dcterms:extent><![CDATA[7 p.]]></dcterms:extent>
    <dcterms:language><![CDATA[Ingl&eacute;s]]></dcterms:language>
    <dcterms:type><![CDATA[Art&iacute;culo]]></dcterms:type>
    <dcterms:identifier><![CDATA[10.1016/j.rechem.2023.101115]]></dcterms:identifier>
</rdf:Description><rdf:Description rdf:about="https://riquim.fq.edu.uy/items/show/6226">
    <dcterms:title><![CDATA[<strong>Identification of pyrazolotriazinones as potential agents for hyperuricemia treatment by using in vitro and in silico studies</strong>]]></dcterms:title>
    <dcterms:subject><![CDATA[HIPERURICEMIA
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    <dcterms:subject><![CDATA[ESTUDIOS IN VITRO
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    <dcterms:subject><![CDATA[ESTUDIOS IN SILICO
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    <dcterms:subject><![CDATA[PIRAZOLOTRIAZINONAS
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    <dcterms:subject><![CDATA[BIBLIOGRAFIA NACIONAL QUIMICA
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    <dcterms:subject><![CDATA[2020
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    <dcterms:abstract><![CDATA[Heterocyclic compounds structurally related to purine bases have been described as anticonvulsants, antifungal, antiviral, anticancer, enzyme inhibitors, among others. In this work, pyrazolo[3,4-d][1-3]triazin-4-ones (2) and pyrazolo[4,3-d][1-3] triazin-4-ones (3) derivatives were evaluated as xanthine oxidase (XO) inhibitors. Compounds 3 showed the best activity with IC50 values range of 0.9&ndash;2.9 &mu;M. While the inhibition performance of pyrazolotriazinones was not more active than reference inhibitor allopurinol ( IC50 = 0.247 &plusmn; 0.004) &mu;M, these nuclei provide a platform for new and more potent XO inhibitors. Accordingly, molecular modeling methods were carried out to understand the compounds-enzyme binding mode. First, we have performed a qualitative SAR study using the MOE&trade; SAR tool. This study showed three common scaffolds and the most active was identified. These results are certainly valuable and will be taken into account in future synthesis of structurally related compounds. Furthermore, QSAR 2D and 3D studies were performed and structural requirements for the activity are reported. The obtained results led us to present the structural improvements for the rational design and synthesis of new pyrazolotriazinone derivatives with greater xanthine oxidase inhibitory activity than allopurinol.
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    <dcterms:creator><![CDATA[<strong>Sci&uacute;, M. Lourdes</strong>]]></dcterms:creator>
    <dcterms:creator><![CDATA[<strong>Santi, M. Daniela</strong>]]></dcterms:creator>
    <dcterms:creator><![CDATA[<strong>Cantero, Jorge</strong>]]></dcterms:creator>
    <dcterms:creator><![CDATA[<strong>Colomer, Juan P.</strong>]]></dcterms:creator>
    <dcterms:creator><![CDATA[<strong>Paulino Zunini, Margot</strong>]]></dcterms:creator>
    <dcterms:creator><![CDATA[<strong>Ortega, M. Gabriela</strong>]]></dcterms:creator>
    <dcterms:creator><![CDATA[<strong>Moyano, E. Laura</strong>]]></dcterms:creator>
    <dcterms:source><![CDATA[SN Applied Sciences v. 2, 2020. -- p. 1-14.--e1298
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    <dcterms:publisher><![CDATA[Springer Nature
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    <dcterms:date><![CDATA[2020
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    <dcterms:rights><![CDATA[<p><strong>Informaci&oacute;n sobre Derechos de Autor</strong> (Por favor lea este aviso antes de abrir los documentos u objetos)<strong> La legislaci&oacute;n uruguaya protege el derecho de autor </strong>sobre toda creaci&oacute;n literaria, cient&iacute;fica o art&iacute;stica, tanto en lo que tiene que ver con sus derechos morales, como en lo referente a los derechos patrimoniales con sujeci&oacute;n a lo establecido por el derecho com&uacute;n y las siguientes leyes (LEY 9.739 DE 17 DE DICIEMBRE DE 1937 SOBRE PROPIEDAD LITERARIA Y ARTISTICA CON LAS MODIFICACIONES INTRODUCIDAS POR LA LEY DE DERECHO DE AUTOR Y DERECHOS CONEXOS No. 17.616 DE 10 DE ENERO DE 2003, LEY 17.805 DE 26 DE AGOSTO DE 2004, LEY 18.046 DE 24 DE OCTUBRE DE 2006 LEY 18.046 DE 24 DE OCTUBRE DE 2006) ADVERTENCIA - La consulta de este documento queda condicionada a la aceptaci&oacute;n de las siguientes condiciones de uso: Este documento es &uacute;nicamente para usos privados enmarcados en actividades de investigaci&oacute;n y docencia. No se autoriza su reproducci&oacute;n con fines de lucro. Esta reserva de derechos afecta tanto los datos del documento como a sus contenidos. En la utilizaci&oacute;n o cita de partes debe indicarse el nombre de la persona autora.</p>
<p>&nbsp;</p>
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    <dcterms:format><![CDATA[Pdf
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    <dcterms:language><![CDATA[Ingl&eacute;s
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    <dcterms:type><![CDATA[Art&iacute;culo
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    <dcterms:identifier><![CDATA[https://doi.org/10.1007/s42452-020-2756-6
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</rdf:Description><rdf:Description rdf:about="https://riquim.fq.edu.uy/items/show/5585">
    <dcterms:title><![CDATA[<strong>Alcoholismo e hiperuricemia : 1988-1998</strong>]]></dcterms:title>
    <dcterms:subject><![CDATA[<strong>ALCOHOLISMO</strong>]]></dcterms:subject>
    <dcterms:subject><![CDATA[<strong>HIPERURICEMIA</strong>]]></dcterms:subject>
    <dcterms:publisher><![CDATA[Biblioteca-FQ]]></dcterms:publisher>
    <dcterms:date><![CDATA[1998]]></dcterms:date>
    <dcterms:format><![CDATA[Papel]]></dcterms:format>
    <dcterms:format><![CDATA[PDF]]></dcterms:format>
    <dcterms:language><![CDATA[Ingl&eacute;s]]></dcterms:language>
    <dcterms:type><![CDATA[Bibliograf&iacute;a]]></dcterms:type>
    <dcterms:temporal><![CDATA[1977-1997]]></dcterms:temporal>
</rdf:Description></rdf:RDF>
