News

Please find below all relevant news regarding our Group.
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Another 2020 publication from the group at ACS Catalysis is on-line

06/12/2020
So glad to announce our second ACS Catal. paper for 2020 is already available on-line.

We are very happy to share our last publication at ACS Catalysis journal, entitled "Pd–Catalyzed (3 + 2) Heterocycloadditions between Alkylidenecyclopropanes and Carbonyls: Straightforward Assembly of Highly Substituted Tetrahydrofurans" and authored by F. Verdugo, E. da Concepción, R. Rodiño, M. Calvelo, J. L. Mascareñas and F. López

Abstract:
A Pd catalyst made from a Pd(0) source and a bulky biaryl phosphine ligand promotes highly efficient intramolecular (3 + 2) heterocycloadditions between alkylidenecyclopropanes (ACPs) and carbonyls. The annulations provide a straightfor-ward access to fused polycyclic systems featuring β-methylene tetrahydrofuran moieties. DFT data support a pallada-ene process and shed light on the critical role of hemilabile interactions between the Pd center and the bulky biaryl phosphine. Significantly, these Pd(0) catalysts are also effective for promoting intermolecular formal cycloadditions between ACPs and trifluoromethyl ketones, thus providing for a direct entry to chiral THFs bearing trifluoromethyl–substituted carbons



External link: https://pubs.acs.org/doi/10.1021/acscatal.0c01827

A brand new chembio field paper is on-line, available at Chem. Eur. J.

04/01/2020
Glad to announce another S. Learte's first author publication (two in a row) has been accepted at "Chemistry, a European Journal"

Continuing with the nice results coming out during the beginning of 2020, we are very pleased to share our last publication at Chem. Eur. J., entitled "Assembly of a ternary metallopeptide complex at specific DNA sites mediated by an AT‐Hook adaptor" and authored by S. Learte-Aymamí, J. Rodríguez, E. Vázquez and J. L. Mascareñas.

Abstract:
We describe the nickel(II)‐mediated self‐assembly of a multimeric DNA binder composed by two metal‐chelating peptides derived from a bZIP transcription factor ( brHis 2 ) and one short AT‐hook domain equipped with two bipyridine ligands ( HkBpy 2 ). These peptides reversibly assemble in the presence of Ni(II) ions at selected DNA sequences of 13 base pairs.




External link: https://chemistry-europe.onlinelibrary.wiley.com/doi/abs/10.1002/chem.202001277

Our last paper at Angew. Chem. Int. Ed. is available as accepted article

03/11/2020
Pleased to announce our most recent ACIE manuscript has been accepted, and it's already on-line

We are very happy to share here that our research article at Angew. Chem. Int. Ed., entitled "Intracellular reactions promoted by bis‐histidine miniproteins stapled with Pd(II) complexes" and authored by J. L. Mascarenas, S. Learte-Aymamí, C. Vidal and A. Gutiérrez-González, has been accepted and it's already available through the journal website.

Abstract: The generation of catalytically active metalloproteins inside living mammalian cells is a major research challenge at the interface between catalysis and cell biology. Herein we demonstrate that basic domains of bZIP transcription factors, mutated to include two histidine residues at i, i+4 positions, react with palladium (II) sources to generate catalytically active, stapled pallado‐miniproteins. The resulting constrained peptides are efficiently internalized into living mammalian cells, where they can perform palladium‐promoted depropargylation reactions, without cellular fixation. Control experiments confirm the requirement of the peptide scaffolding and the palladium staple for attaining the intracellular reactivity.



External link: https://onlinelibrary.wiley.com/doi/10.1002/anie.202002032

Last publication for February 2020, in collaboration with J. Mosquera and Liz-Marzán's group

02/27/2020
Very happy to announce our first ACS nano is already available on-line

Completing this amazing February 2020, we are glad to post our first publication at ACS nano journal, entitled "Reversible Control of Protein Corona Formation on Gold Nanoparticles Using Host–Guest Interactions" and authored by J. Mosquera, I. García, M. Henriksen-Lacey, M. Martínez-Calvo, M. Dhanjani, J. L. Mascareñas and L. M. Liz-Marzán.

Abstract:
When nanoparticles (NPs) are exposed to biological media, proteins are adsorbed, forming a so-called protein corona (PC). This cloud of protein aggregates hampers the targeting and transport capabilities of the NPs, thereby compromising their biomedical applications. Therefore, there is a high interest in the development of technologies that allow control over PC formation, as this would provide a handle to manipulate NPs in biological fluids. We present a strategy that enables the reversible disruption of the PC using external stimuli, thereby allowing a precise regulation of NP cellular uptake. The approach, demonstrated for gold nanoparticles (AuNPs), is based on a biorthogonal, supramolecular host–guest interactions between an anionic dye bound to the AuNP surface and a positively charged macromolecular cage. This supramolecular complex effectively behaves as a zwitterionic NP ligand, which is able not only to prevent PC formation but also to disrupt a previously formed hard corona. With this supramolecular stimulus, the cellular internalization of AuNPs can be enhanced by up to 30-fold in some cases, and even NP cellular uptake in phagocytic cells can be regulated. Additionally, we demonstrate that the conditional cell uptake of purposely designed gold nanorods can be used to selectively enhance photothermal cell death.


External link: https://twitter.com/MetBioCat/status/1235837116090691585

One further publication for this month, in collaboration with E. Vázquez and J. Martínez-Costas groups

02/26/2020
So glad to announce our Sci. Rep. paper is already available on-line.

Just continuing this beginning of 2020 year, we are very happy to share our last publication at Scientific Reports journal, entitled "MitoBlue as a tool to analyze the mitochondria-lysosome communication" and authored by M. I. Sánchez, Y. Vida, E. Pérez-Inestrosa, J. L. Mascareñas, E. Vázquez, A. Sugiura, and J. Martínez Costas.

Abstract:
MitoBlue is a fluorescent bisamidine that can be used to easily monitor the changes in mitochondrial degradation processes in different cells and cellular conditions. MitoBlue staining pattern is exceptional among mitochondrial dyes and recombinant fluorescent probes, allowing the dynamic study of mitochondrial recycling in a variety of situations in living cells. MitoBlue is a unique tool for the study of these processes that will allow the detailed characterization of communication between mitochondria and lysosomes.



External link: https://twitter.com/MetBioCat/status/1233074377048064007

Our first accepted publication for 2020 is already on-line

02/14/2020
Really pleased to announce our latest ACS Catal. paper is available as a just accepted manuscript

Starting this brand new 2020 year... we are glad to announce our most recent publication at ACS Catalysis journal, entitled "Palladium-catalyzed formal (4+2) cycloaddition between alkyl amides and dienes initiated by the activation of C(sp3)−H bonds" and authored by B. Cendón, M. Font, J. L. Mascareñas and M. Gulías, is already available as just accepted manuscript.


Abstract:
We report a formal (4+2) cycloaddition between alkyl-nosylamides and dienes enabled by a palladium-catalyzed activation of C(sp3)−H bonds beta to the amide group. This atom economical reaction which proceeds under operationally simple conditions, is compatible with a wide variety of dienes, and provides a straightforward method to assemble different types of saturated lactams. The annulation is favored over alternative pathways in part because of the key role of the extra double bond of the diene partner. The use of suitable nitrogen-based additives as palladium ligands, which enable the C(sp3)−H activation without interfering in subsequent steps of the catalytic cycle, is also critical for the success of the reaction.


External link: https://twitter.com/MetBioCat/status/1230768577738764290