Martin Calvelo Souto

University of Barcelona | UB · Facultad de Química

Pyrroles and indoles bearing N‐allenyl tethers participate in a variety of iridium‐catalyzed cycloisomerization processes initiated by a C−H activation step, to deliver a diversity of synthetically relevant azaheterocyclic products. By appropriate selection of the ancillary ligand and the substitution pattern of the allene, the reactions can diverg...

Pyrroles and indoles bearing N‐allenyl tethers participate in a variety of iridium‐catalyzed cycloisomerization processes initiated by a C‐H activation step, to deliver a diversity of synthetically relevant azaheterocyclic products. By appropriate selection of the ancillary ligand and the substitution pattern of the allene, the reactions can diverg...

Antimicrobial peptides (AMPs) are increasingly recognized as potent therapeutic agents, with their selective affinity for pathological membranes, low toxicity profile, and minimal resistance development making them particularly attractive in the pharmaceutical landscape. This study offers a comprehensive analysis of the interaction between specific...

Cyclic peptides (CPs) formed by alternation of D- and L-amino acids (D,L-CPs) can self-assemble into nanotubes (SCPNs) by parallel or/and antiparallel stacking. Different applications have been attributed to these nanotubes, including the disruption of lipid bilayers of specific compositions and the selective transport of ions throughout membranes....

Pd⁰ catalysts featuring phosphorus‐based monodentate ligands can detour the reactivity of carbonyl‐tethered alkylidenecyclopropanes (ACPs) from standard (3+2) cycloadditions towards tandem cycloisomerization/cross‐coupling processes. This new reactivity lies on the formation of key π‐allyl oxapalladacyclic intermediates, which are subsequently trap...

Self-assembled cyclic peptide nanotubes with alternating D- and L-amino acid residues in the sequence of each subunit have attracted a great deal of attention due to their potential for new nanotechnology and biomedical applications, mainly in the field of antimicrobial peptides. Molecular dynamics simulations can be used to characterize these syst...

Pd(0) catalysts featuring phosphorous‐based monodentate ligands can detour the reactivity of carbonyl‐tethered alkylidenecyclopropanes (ACPs) from standard (3+2) cycloadditions towards tandem cycloisomerization / cross‐coupling processes. This new reactivity lies on the formation of key π‐allyl oxapalladacyclic intermediates, which are subsequently...

Host defence peptides (HDPs) are short cationic peptides that play a key role in the innate immune response of all living organisms. Their action mechanism does not depend on the presence of protein receptors, but on their ability to target and disrupt the membranes of a wide range of pathogenic and pathologic cells which are recognized by their sp...

We report a versatile, highly enantioselective intramolecular hydrocarbonation reaction that provides a direct access to heteropolycyclic systems bearing chiral quaternary carbon stereocenters. The method, which relies on an iridium(I)/bisphosphine chiral catalyst, is particularly efficient for the synthesis of five‐, six‐ and seven‐membered fused...

Self-assembling cyclic peptide nanotubes have been shown to function as synthetic, integral transmembrane channels. The combination of natural and nonnatural aminoacids in the sequence of cyclic peptides enables the control not only of their outer surface but also of the inner cavity behavior and properties, affecting, for instance, their permeabil...

We report an enantioselective Ir-catalyzed hydrocarbonation towards pyrrole and indole polycyclic scaffolds featuring five-, six- or seven-membered rings, with tertiary and all-carbon quaternary stereocenters. The process can be coupled with the desymmetrization of prochiral centers to obtain pyrrole- and indole-fused scaffolds with either vicinal...

Self-assembling cyclic peptide nanotubes can form nanopores when they are inserted in lipid bilayers, acting as ion and/or water permeable channels. In order to improve the versatility of these systems, it is possible to specifically design cyclic peptides with a combination of natural and non-natural amino acids, enabling the control of the nature...

The era of the explosion of immersive technologies has bumped head-on with the coronavirus disease 2019 (COVID-19) global pandemic caused by the severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2). The proper understanding of the three-dimensional structures that compose the virus, as well as of those involved in the infection process and...

A handful of singular structures and laws can be observed in nature. They are not always evident but, once discovered, it seems obvious how to take advantage of them. In chemistry, the discovery of reproducible patterns stimulates the imagination to develop new functional materials and technological or medical applications. Two clear examples are h...

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 pallad...

Rational design and development of new nanosystem usually relies on empirical approaches as well as a fair degree of serendipity. Understanding how nanosystems behave at molecular level is of great importance for potential biomedical applications. In this work we describe a nanosystem composed by two natural compounds, Vitamin E and Sphingomyelin,...

Cyclic peptides with disc‐shaped structures have emerged as potent building blocks for the preparation of new biomaterials in fields ranging from biological to material science. In this work, we analyze in depth the self‐assembling properties of a new type of cyclic peptides based on the alternation of α‐residues and cyclic δ‐amino acids (α,δ‐CPs)....

We describe the discovery of unprecedented annulation processes of 1,7-allenedienes, promoted by Pt or Au catalysts. These transformations allowed to unveil mechanistic pathways that had not been previously observed in reactions involving carbophilic catalysis. In particular, we have found that allenedienes bearing a silyl ether at the carbon tethe...

The basket-like geometry of cyclodextrins (CDs), with a cavity able to host hydrophobic groups, makes these molecules well suited for a large number of fundamental and industrial applications. Most of the established CD-based applications rely on trial and error studies, often ignoring key information at the atomic level that could be employed to d...

A cyclic hexapeptide with three pyridyl moieties connected to its backbone forms a hydrogen‐bonded dimer, which tightly encapsulates a single xenon atom, like a pearl in its shell. The dimer imprints its shape and symmetry to the captured xenon atom, as demonstrated by ¹²⁹Xe NMR spectroscopy, single‐crystal X‐ray diffraction, and computational stud...

Eng eingeschlossen: Ein cyclisches Hexapeptid mit drei Pyridylgruppen an der Hauptkette bildet ein wasserstoffbrückengebundenes Dimer, das ein einzelnes Xenon‐Atom eng einkapselt. Die Dimere ordnen sich hierarchisch zu röhrenartigen Strukturen in einer porösen supramolekularen Architektur an, deren Hohlräume durch kleine Moleküle und Gase ausgefüll...

"Intelligent" materials based on synthetic small molecules that become functional only under specific conditions provide new opportunities for developing regulated systems aimed to a large number of applications. For instance, biologically active supramolecular entities that are sensitive to environmental conditions, such as the presence of bacteri...

The β‐sheet‐type structures derived from the stacking of α,γ‐cyclic peptides to form peptides nanotubes can provide different topoisomers, nonequivalent cyclic peptide stacks generated by the relative rotation through the channel axis of one cyclic peptide with respect to the next component. This rotation generates a series of cyclic peptide dimers...

We report an Ir(I)-catalyzed cycloisomerization methodology that provides access to carbocyclic systems bearing exo-alkene moieties from alkynyl-equipped acyclic precursors. The method relies on the C-H activation of olefinic and (het-ero)aromatic C(sp2)–H bonds, followed by an exo-cyclization to a tethered alkyne, and provides interesting cyclic d...

A new method for switching between structures consisting of equivalent discrete and flexible objects with different particle representation and object configuration, including different resolution levels (number of particles per object), is reported. The method is fully general since it does not require any extra code nor additional database elemen...

Membrane channels are transmembrane-spanning structures that have an internal cavity that allow the migration of different ions and molecules. Inspired by the natural systems, chemists have created a variety of synthetic mimicries. Frequently, self-assembling methods were used to prepare the complex structure of these molecular channels. Although i...

A molecular dynamics study on internally functionalized peptide nanotubes composed of α- and γ-amino acids self-assembled in lipid bilayers is presented. One of the main advantages of peptide nanotubes composed of γ-amino acids is that the properties of their inner cavities can be tuned by introducing different functions on β-carbon of the γ-amino...