Clarisa Villegas Gómez

Click chemistry represents a powerful strategy for the efficient construction of biologically relevant heterocyclic scaffolds. Herein, seven topsentin and nortopsentin analogues featuring a bis(indolyl)-1,2,3-triazole framework were synthesized via Cu(I)-catalyzed azide-alkyne cycloaddition (CuAAC). Key azide and alkyne precursors were prepared through protection, reduction, nucleophilic substitution, electrophilic aromatic substitution, Sonogashira cross-coupling, and deprotection reactions. The target analogues were obtained in yields ranging from 15 to 77% and characterized by NMR spectroscopy and mass spectrometry. Their antibacterial potential was assessed against E. faecalis and E. coli. However, none of the synthesized compounds displayed antibacterial activity against either strain under the experimental conditions evaluated in this study.

3,4-dihydrocoumarins and spiro compounds constitute an important class of privileged frameworks present in a wide variety of natural and synthetic molecules with diverse applications. In this study, we developed an organocatalytic methodology for the construction of complex and diverse chiral spiro-bridged 3,4-dihydrocoumarins through a Diels–Alder/Nucleophilic ring-closing cascade via trienamine activation. The reaction proceeds efficiently with different trienamine precursors and a range of coumarin-3-carboxamides, which act as both dienophile and intramolecular nucleophile species. This process affords the desired products in good yields and with a high degree of stereocontrol. Furthermore, several transformations on the newly formed spiro-piperidone ring demonstrate the synthetic utility of the obtained compounds.

Although ammonium salts derived from ethyl nitroacetate have been known for decades, only limited information about their properties has been reported. The synthesis of seven such salts, obtained from primary, secondary and tertiary alkylamines, as well as choline and amidine, prompted us to investigate their solvent- and cation-dependent stability. SC-XRD analysis of pyrrolidine salt provided key insights into their structural features. Furthermore, we evaluated their potential use as ionic liquids in green chemistry applications, including caffeine extraction from black tea (Camellia sinensis) leaves and CO2 chemisorption–desorption.

Bile acids are a major class of compounds derived from cholesterol catabolism and have been linked to diverse biological activities, including anti-inflammatory, anticancer, antimicrobial, antifungal, and neuroprotective effects. The potential therapeutic applications of bile acids have been reported in various conditions, including hepatic disorders, nonalcoholic fatty liver disease, and the regulation of glycemic control. In this study, chenodeoxycholic acid (CDCA), as well as three new 1,2,3-triazole-linked CDCA hybrids and various semisynthetic derivatives, were evaluated for their effects on acute TPA-induced ear edema in mice. The results demonstrate that CDCA and its derivatives exhibit topical anti-inflammatory properties. However, the 1,2,3-triazole-linked CDCA hybrids did not present topical anti-inflammatory activity. The anti-inflammatory effects of CDCA (50 mg/kg p.o.) were similar to those of indomethacin (8 mg/kg p.o.) in models of acute and chronic TPA-induced ear edema. Molecular docking indicated that CDCA may interact with multiple molecular targets, including the nuclear receptor FXR, inflammatory mediators (TNF-α, IL-1β) and the transcriptional regulator NF-κB p65. End-point free-energy calculations (MM/GBSA) supported these trends, reinforcing the hypothesis of multi-target engagement. These in vitro/theoretical studies provide an experimental follow-up to consider CDCA as a scaffold for multi-target modulation within metabolic and inflammatory pathways.

"Los benzopiranos se han consolidado como estructuras privilegiadas debido a su amplio rango de aplicaciones biológicas, particularmente como agentes antimicrobianos, antivirales y antiinflamatorios. Esto ha impulsado la necesidad de ampliar la biblioteca de moléculas que contienen este núcleo, al mismo tiempo que se busca un control preciso sobre su estereoquímica. En este trabajo se describe la síntesis de una serie de derivados de 2-fenil-2H-cromen-3-carbaldehído mediante una reacción de adición oxa-Michael, utilizando como organocatalizador el (S)-(–)-α,α-difenil-2-pirrolidinmetanol trimetilsilil éter. Esta metodología permitió obtener rendimientos satisfactorios, en un rango del 65% al 90%, lo que evidencia la eficacia de este tipo de catalizadores para tales transformaciones.Posteriormente, se procedió a la funcionalización del núcleo croménico a través de una reacción de Knoevenagel con cianoacetato de etilo, seguida de una cicloadición de Diels–Alder empleando un derivado de 2,4-hexadienal como precursor del dieno. Estas transformaciones permiten explorar nuevas regiones del espacio químico, lo que incrementa la diversidad estructural y el potencial biológico de este tipo decompuestos."

In this work we report the stereoselective synthesis of 2H-flavenes via an Aminocatalytic privileged Diversity-Oriented Synthesis (ApDOS) strategy. An oxa-Michael cyclization between salicylaldehydes and an iminium intermediate from cinnamaldehyde and the Hayashi–Jørgensen catalyst produced flavenes at up to 81% yield and 90% ee under optimal conditions (PhCOOH, toluene, 40 °C, 18 h). In general, the reaction proceeds with good yields. Further, reactions with a stabilized carbanion produced Knoevenagel-type adducts, explained by electronic delocalization, HSAB considerations, and kinetic/thermodynamic factors. The resulting polycyclic products show potential as dienophiles in Diels–Alder reactions, offering a valuable framework for future bioactive compound development.

This work reports progress in the semi-synthetic modification of cassane-type diterpenes isolated from Coulteria platyloba, a plant of ethnopharmacological relevance. The approach involves a sequence of transformations, including oxidative aromatization, ring opening, and Knoevenagel condensation, to generate key intermediates for further diversification. Preliminary studies demonstrated the feasibility of organocatalytic reactions under trienamine activation, including a successful Diels–Alder cycloaddition. The initial steps were achieved with good yields and high purity, underscoring the potential of this strategy to access novel molecular scaffolds through efficient and sustainable methods aligned with the principles of Diversity-Oriented Synthesis (DOS).

Herein, we present the development of new organocatalytic cascade reactions for the synthesis and diversification of privileged structures, using trienamine activation as a key step. An important feature of this process is that once it is completed, it is possible to generate new reactive species within the same molecule. In this sense, a series of consecutive reactions can be carried out, incorporating dienophiles with a nucleophilic addition functionality. As a result, complex and diverse compounds can be accessed through simple starting materials.

El Parkinson, es una de las enfermedades neurodegenerativas que ha sido prevalenteen la sociedad a lo largo de los años, afectando a millones de personas en todo elmundo. Actualmente, existe un arsenal farmacéutico asistiendo al control sintomáticode la enfermedad como temblores, rigidez, deterioro de la postura y equilibrio. Larasagilina, perteneciente a la familia de la propargilamina, es un inhibidor de la enzimamonoamino oxidasa B (MAO-B) la cual degrada la dopamina. Este fármaco, se puedeadministrar tanto en forma de monoterapia como de terapia combinada, fungiendocomo adyuvante con la levodopa. El artículo se centra en dar un panorama generaltomando desde los puntos primarios hasta los más puntuales como su mecanismo deacción.

A medida que avanzamos, el campo de la química plantea constantemente estrategias que permitan diseñare innovar la manera en la que se sintetizan los productos químicos, especialmente desde una perspectivamás sostenible y eficiente, que no solo permita ampliar la creación y posterior aplicación de nuevasreacciones, sino que también fomente la aparición de enfoques emergentes que ofrezcan tanto nuevasperspectivas como alternativas para la solución de problemas existentes, la organocatálisis como rama enpleno auge de la síntesis orgánica es una herramienta que en los últimos años ha tenido gran prosperidad enlas aplicaciones de diversificación y construcción de nuevas moléculas orgánicas.