Archivo de la categoría: Noticias

Noticias

Nuevo artículo, Bioorg. Med. Chem. 07.21

Pyrrolo[1,2-a]quinoxal-5-inium Salts and 4,5-dihydropyrrolo[1,2-a]quinoxalines: Synthesis, Activity and Computational Docking for Protein Tyrosine Phosphatase 1B

Patricia Sánchez-Alonso, Mercedes Griera, Javier García-Marín, Manuel Rodríguez-Puyol,* Ramón Alajarín,* Juan J.Vaquero,* Diego Rodríguez-Puyol*

Bioorg. Med. Chem., 2021, In Press
DOI: 10.1016/j.bmc.2021.116295

Protein tyrosine phosphatase (PTP1B) is an interesting therapeutical target for diabetes, obesity, heart disease and cancer. As such, inhibition of PTP1B using orally administered drugs is still being pursued by academia and pharmaceutical companies. The failure of catalytic-site inhibitors led to the focus in this field being switched to allosteric inhibitors. To date, the non-competitive inhibitors that have reached clinical trials target the site formed by the <3/<6/<7 tunnel or the site found in a disordered C-terminal non-catalytic segment. Herein, pyrrolo[1,2-a]quinoxal-5-inium salts and 4,5-dihydropyrrolo[1,2-a]quinoxalines are synthesized from pyrrolo[1,2-a]quinoxalines by alkylation and reduction, respectively. These compounds showed no toxicity in HepG2 cells and exhibited inhibitory activity against PTP1B, with inhibition percentages of between 37% and 53% at 1 μM and activities (IC50) of between 0.25 and 1.90 μM. The inhibitory activity against T-cell protein tyrosine phosphatase (TC-TPT) was also assayed, with 4,5-dihydropyrrolo[1,2-a]quinoxalines being found to be slightly more active and selective. Compounds from the two series behave as insulin mimetics since they exhibit enhancement of glucose uptake in C2C12 cells. Computational docking studies provide information about the putative binding mode for both series and the preference for the <3/<6/<7 allosteric tunnel.
Noticias

Nuevo artículo, ChemMedChem 06.21

A computer-driven scaffold-hopping approach generating new PTP1B inhibitors from the pyrrolo[1,2-a]quinoxaline core

Javier García-Marín,* Mercedes Griera, Ramón Alajarín, Manuel Rodríguez-Puyol, Diego Rodríguez-Puyol, Juan J. Vaquero*

ChemMedChem, 2021, Accepted Article
DOI: 10.1002/cmdc.202100338

Protein tyrosine phosphatase 1B is a very promising target for the treatment of metabolic disorders such as type II diabetes mellitus. Although it was validated as a promising target for this disease more than 30 years ago, as yet there is no drug in advanced clinical trials, and its biochemical mechanism and functions are still being studied. In the present study, based on our experience generating PTP1B inhibitors, we have developed and implemented a scaffold-hopping approach to vary the pyrrole ring of the pyrrolo[1,2- a ]quinoxaline core, supported by extensive computational techniques aimed to explain the molecular interaction with PTP1B. Using a combination of docking, molecular dynamics and end-point free-energy calculations, we have rationally designed a hypothesis for new PTP1B inhibitors, supporting their recognition mechanism at a molecular level. After the design phase, we were able to easily synthesize proposed candidates and their evaluation against PTP1B was found to be in good concordance with our predictions. Moreover, the best candidates exhibited glucose uptake increments in cellulo modell, thus confirming their utility for PTP1B inhibition and validating this approach for inhibitors design and molecules thus obtained.
Noticias

Nuevo artículo, Dyes and Pigments 05.21

A new family of fluorescent pyridazinobenzimidazolium cations with DNA binding properties

Pedro Bosch, Gema Marcelo, Alejandra Matamoros-Recio, David Sucunza*, Francisco Mendicuti, Alberto Domingo, Juan J. Vaquero*

Dyes Pigm., 2021, In Press
DOI: 10.1016/j.dyepig.2021.109443

A series of novel azonia aromatic heterocycles formed by a pyridazinobenzimidazolium system has been synthesized. Spectrofluorimetric and circular dichroism measurements, as well as theoretical simulations for these materials, have shown their interesting fluorescence properties and DNA-binding ability. Stoichiometries and binding constants were obtained by fluorescence and the induced circular dichroism spectra analysis. Moreover, the potential of these compounds for cell staining has been investigated in living HeLa cells by confocal microscopy imaging.
Noticias

Capítulo libro, Advances in Heterocyclic Chemistry 03.21

Recent developments in the chemistry of BN-aromatic hydrocarbons

Alberto Abengózar, Patricia García-García, Manuel A. Fernández-Rodríguez, David Sucunza*, Juan J. Vaquero*

Advances in Heterocyclic Chemistry, 2021, In Press, Corrected Proof
DOI: 10.1016/bs.aihch.2021.01.001

Versión final en abierto hasta el 21 de abril de 2021 en el siguiente enlace:
https://authors.elsevier.com/a/1cgCsErrnROHF

Heterocycles containing both N and B heteroatoms in their structure were first reported by Dewar in the middle of the last century. However, they received little attention until the early years of this century, when several groups revisited these compounds due to their interest in BN/CC isosterism. As a result of these systematic studies, very significant advances have been made in our understanding of the chemistry of these BN-heterocycles. The purpose of this review is to summarize the most significant advances in the last two decades as regards the development of synthetic strategies and studies of their reactivity, as well as to provide an overview of their general properties and main applications.
Noticias

Portadas 2020

Este año el grupo ha contribuido en dos de sus artículos en portadas de las revistas:

· Chem Med Chem
Pyrrolo[1,2‐a]quinoxalines: Insulin Mimetics that Exhibit Potent and Selective Inhibition against Protein Tyrosine Phosphatase 1B
Javier García‐Marín, Mercedes Griera, Patricia Sánchez‐Alonso, Bruno Di Geronimo, Francisco Mendicuti, Manuel Rodríguez‐Puyol*, Ramón Alajarín*, Beatriz de Pascual‐Teresa, Juan J. Vaquero*, Diego Rodríguez‐Puyol*

The Front Cover shows a C2C12 cell with the inhibitor 4‐benzylpyrrolo[1,2‐a]quinoxaline targeting the α3/α6/α7 tunnel in the Protein Tyrosine Phosphatase 1B (PTP1B) represented as a ribbon diagram. The insulin receptor (clear green) and the glucose transporter (clear yellow) shown at the cell membrane are involved in the glucose uptake by the cell. The inhibition of PTP1B by this molecule and their analogues produces an insulin mimetic effect. This is indicated by red arrows for the glucose molecules (in sticks) crossing the cell membrane to the cytosol.

· Org Lett
Selective Synthesis of Phenanthrenes and Dihydrophenanthrenes via Gold-Catalyzed Cycloisomerization of Biphenyl Embedded Trienynes
Ana Milián, Patricia García-García*, Adrián Pérez-Redondo, Roberto Sanz, Juan J. Vaquero, and Manuel A. Fernández-Rodríguez*

The cover art illustrates the solvent-controlled gold(I)-catalyzed selective synthesis of phenanthrenes and dihydrophenanthrenes from easily available biphenyl-embedded trienynes. Notably, the phenanthrene synthesis developed is complementary to the well-studied strategy that produces regioisomeric phenanthrenes, resulting from the competitive nucleophilic addition of biphenyl to the activated alkyne. In addition, the isolation of the cyclobutenyl derivative depicted in the figure accounts for the participation of cyclobutene species in the catalytic cycle.
Noticias

Nuevo artículo, Catalysts 10.20

Gold-Catalyzed Synthetic Strategies towards Four-Carbon Ring Systems

Guillermo Otárola, Juan J. Vaquero, Estíbaliz Merino*, Manuel A. Fernández-Rodríguez*

Catalysts, 2020, Early View
DOI: 10.3390/catal10101178

Four carbon ring systems are frequently present in natural products with remarkable biological activities such as terpenoids, alkaloids, and steroids. The development of new strategies for the assembly of these structures in a rapid and efficient manner has attracted the interest of synthetic chemists for a long time. The current research is focused mainly on the development of synthetic methods that can be performed under mild reaction conditions with a high tolerance to functional groups. In recent years, gold complexes have turned into excellent candidates for this aim, owing to their high reactivity, and are thus capable of promoting a wide range of transformations under mild conditions. Their remarkable efficiency has been thoroughly demonstrated in the synthesis of complex organic molecules from simple starting materials. This review summarizes the main synthetic strategies described for gold-catalyzed four-carbon ring formation, as well as their application in the synthesis of natural products.
Noticias

Nuevo artículo, Nefrología 10.20

El sistema pHLIP como vehículo de microRNA en el rinón

Verónica Miguel, Carlos Rey, José Luis Aceña, Francisco Maqueda, Carlos Fernández-Hernando, Diego Rodríguez-Puyol, Juan J. Vaquero, Santiago Lamas

Nefrología, 2020
DOI: 10.1016/j.nefro.2020.05.007

Los microRNA (miRNA) son ARN endógenos de pequeño tamaño que regulan la expresión génica a través de la represión postranscripcional de sus ARN mensajeros diana. El estudio de los cambios en la expresión de ciertos miRNA en el riñón ha proporcionado evidencias sobre su papel patogénico y potencial terapéutico en nefrología. En esta revisión proponemos un abordaje de nanotecnología basado en la unión de análogos o inhibidores de miRNA formados por ácidos peptidonucleicos (PNA) a péptidos con una estructura transmembrana que es sensible a pH bajo, denominada pHLIP (del inglés pH [low] insertion peptide), apoyándonos en el concepto de que el pH acídico del microambiente tubular renal puede facilitar la concentración y la distribución del complejo pHLIP-PNA en este órgano. En este contexto hemos demostrado por primera vez que la administración dirigida de inhibidores de miR-33 con el sistema pHLIP previene eficazmente del desarrollo de fibrosis renal, abriendo las puertas de esta tecnología a nuevas estrategias de diagnóstico y tratamiento de enfermedades renales.
Noticias

Nuevo artículo, Org Lett 09.2020

Selective Synthesis of Phenanthrenes and Dihydrophenanthrenes via Gold-Catalyzed Cycloisomerization of Biphenyl Embedded Trienynes

Ana Milián, Patricia García-García*, Adrián Pérez-Redondo, Roberto Sanz, Juan J. Vaquero, and Manuel A. Fernández-Rodríguez*

Org. Lett, 2020, ASAP
DOI: acs.orglett.0c03067

Highlighted as Cover Picture: link

Readily available o′-alkenyl-o-alkynylbiaryls, a particular type of 1,7-enynes, undergo a selective cycloisomerization reaction in the presence of a gold(I) catalyst to give interesting phenanthrene and dihydrophenanthrene derivatives in high yields. The solvent used provokes a switch in the evolution of the gold intermediate and plays a key role in the reaction outcome.
Noticias

Nuevo artículo, ChemMedChem 09.2020

Pyrrolo[1,2‐a]quinoxalines: Insulin Mimetics that Exhibit Potent and Selective Inhibition against Protein Tyrosine Phosphatase 1B

Javier García‐Marín, Mercedes Griera, Patricia Sánchez‐Alonso, Bruno Di Geronimo, Francisco Mendicuti, Manuel Rodríguez‐Puyol*, Ramón Alajarín*, Beatriz de Pascual‐Teresa, Juan J. Vaquero*, Diego Rodríguez‐Puyol*

ChemMedChem, 2020, Early View
DOI: 10.1002/cmdc.202000446

Highlighted as Cover Picture: link

PTP1B dephosphorylates insulin receptor and substrates to modulate glucose metabolism. This enzyme is a validated therapeutic target for type 2 diabetes, but no current drug candidates have completed clinical trials. Pyrrolo[1,2‐a]quinoxalines substituted at positions C1–C4 and/or C7–C8 were found to be nontoxic to cells and good inhibitors in the low‐ to sub‐micromolar range, with the 4‐benzyl derivative being the most potent inhibitor (0.24 μm). Some analogues bearing chlorine atoms at C7 and/or C8 kept potency and showed good selectivity compared to TCPTP (selectivity index >40). The most potent inhibitors behaved as insulin mimetics by increasing glucose uptake. The 4‐benzyl derivative inhibited insulin receptor substrate 1 and AKT phosphorylation. Molecular docking and molecular dynamics simulations supported a putative binding mode for these compounds to the allosteric α3/α6/α7 pocket, but inconsistent results in enzyme inhibition kinetics were obtained due to the high tendency of these inhibitors to form stable aggregates. Computational calculations supported the druggability of inhibitors.