Miguel Ángel Vilchis-Reyes

Banana cultivation generates lignocellulosic residues that can be used as renewable feedstocks for value-added materials. In this study, banana rachis was evaluated as a source of cellulose for the synthesis of cellulose acetate. Two chemical pretreatment methods were compared. Although Method 2 provided a higher cellulose extraction yield, cellulose obtained by Method 1 showed a higher acetylation yield and was selected for subsequent experiments. The isolated cellulose was characterized by ATR–FTIR and TEM, which provided information on its chemical characteristics and fibrillar morphology, respectively. Iodine-catalyzed acetylation was optimized using factorial and response surface experimental designs. Iodine and acetic anhydride equivalents significantly affected the reaction yield, whereas temperature and reaction time showed no significant effects within the evaluated range. Under the optimized conditions, cellulose acetate was obtained in an isolated yield of 76 ± 1%. ATR–FTIR and ¹H NMR confirmed acetylation, and a degree of substitution of 2.45 was determined.

This work describes the synthesis and spectroscopic characterization of a 4-aminochalcone–salicylic acid azo conjugate (6) as a potential colon-targeted mutual prodrug. Two synthetic routes were evaluated: one through 4-aminochalcone (4), which afforded compound 6 in 32% overall yield, and an alternative route through the 4-aminoacetophenone–salicylic acid azo intermediate (7), which afforded compound 6 in 33% overall yield. The structure of compound 6 was supported by ¹H and DEPTQ NMR data, including olefinic signals consistent with a trans-configured α,β-unsaturated chalcone system, and by UV–Vis absorptions associated with the aromatic, carbonyl, and azo chromophores. Because azo-bond reduction, gastrointestinal stability, and biological activity were not evaluated in this study, compound 6 is presented as a synthetic and spectroscopic candidate for future assessment as a colon-targeted prodrug platform for inflammatory bowel disease. The ¹H NMR spectrum of compound 6 showed the expected olefinic protons of the α,β-unsaturated system and the corresponding aromatic signals, supporting formation of the proposed conjugated structure. Compound 6 was obtained as a synthetic platform for future prodrug development in inflammatory bowel disease (IBD). Its potential relevance is based on the hypothesis that colonic azoreductases could reduce the azo bond and release the chalcone-derived fragment 4, which has reported antimicrobial activity, and salicylic acid derivative 5, an anti-inflammatory scaffold related to agents used in Crohn’s disease and ulcerative colitis.

Cardiovascular diseases are a global health problem, causing high morbidity and mortality rates, so the search for new therapeutic agents is paramount. We aimed to characterize the vasorelaxant effect of 20 synthetic chiral flavanones using the ex vivo model of rat thoracic aorta precontracted with noradrenaline (0.1 µM) and to look at their binding potential in a molecular docking study. Four flavanones showed a vasorelaxant effect in arteries with and without endothelium. This activity was inhibited in the presence of L-NAME (10 µM) but not with indomethacin (10 µM), atropine (1 µM), or TEA (5 µM). In addition, the median effective concentration (EC50) of flavanones abated the contraction induced by extracellular CaCl2 in arteries without endothelium. The chiral flavanone scaffold without substituent groups and those substituted on the B ring with fluorine (2' and 3') and methoxy (2') exhibited vasorelaxant activity. Molecular docking simulations revealed favorable interactions of the R and S enantiomers of flavanones with amino acids from the catalytic site of the endothelial nitric oxide synthase (eNOS, PDB: 3NOS) and the III and IV domains of the Cav1.2 L-type calcium channels (PDB: 8WE6), two relevant therapeutic targets for the treatment of cardiovascular pharmacology. Therefore, these four synthetic racemic flavanones represent promising scaffolds for the development of new agents with potential therapeutic applications in cardiovascular diseases.

Chalcones are compounds containing an α,β-unsaturated carbonyl group that have been studied due to their structural simplicity, ease of synthesis, and broad spectrum of biological activities. Within this family, nitrochalcones have gained relevance due to the influence of the nitro group (–NO₂) on the modulation of their electronic properties, chemical reactivity, and pharmacological behavior. This review presents a critical analysis of advances in the biological activities and possible mechanisms of action of nitrochalcones and their derivatives, with an emphasis on their structure–activity relationships and therapeutic potential. The available evidence shows that nitrochalcones and their derivatives act as multitarget molecules, capable of intervening in key biological processes such as oxidative stress, mitochondrial dysfunction, inflammation, and cell signaling pathways associated with proliferation and apoptosis. Several studies report anticancer, anti-inflammatory, antiparasitic, antimicrobial, antifungal, and cardiovascular activities, often with favorable selectivity toward pathological cells over healthy cells.

La mancha angular, causada por Phaeoisariopsis griseola, causa una reducción alta en el rendimiento del frijol pelón (Vigna unguiculata), cultivo clave para la seguridad alimentaria en México. Durante un muestreo en Cárdenas, Tabasco, se identificaron dos problemas críticos: (1) incidencia de enfermedades fúngicas en cultivos y (2) desconocimiento de los agricultores sobre patologías específicas, atribuyendo pérdidas a factores climáticos y dependiendo exclusivamente del fungicida comercial. Como solución, la Universidad Juárez Autónoma de Tabasco (UJAT) inició un proyecto interdisciplinario, enfocado en sintetizar compuestos antifúngicos derivados de pirazina mediante química verde (on-water), y en implementar estrategias de divulgación. Se recolectaron muestras de hojas y vainas con lesiones, para su posterior aislamiento del hongo. Paralelamente, se platicó con agricultores para explicar síntomas, ciclos de la enfermedad y prácticas de manejo integrado, logrando informar a productores.

A series of three chalcones with a nitro moiety in ring B (compounds 3a–c) was obtained by following a classic Claisen–Schmidt condensation procedure, which involved hydro-alcoholic conditions at room temperature. The reaction yields are consistently high (>90%), and the spectroscopic data are in close agreement with the anticipated structures. The anti-inflammatory protective effect of 3a–c was evaluated using the carrageenan-induced rat hind paw edema model. Moreover, a Tukey test was conducted to compare the data obtained herein with those for chalcones containing the nitro moiety in Ring A.

Fluorinated chalcones are molecules reported to possess potent anticancer properties against triple-negative breast cancer (TNBC) cells. However, their molecular mechanisms have not yet been fully explored. Using bioinformatics tools, we analyzed the transcriptomes of MDA-MB-231 cells treated with either a novel fluorinated chalcone (compound 3) or a control in order to identify differentially expressed (DE) genes associated with its anticancer activity and determine the biological processes in which these genes are involved. A fluorinated chalcone was synthesized using the Claisen–Schmidt method. The transcriptome of MDA-MB-231 cells was then analyzed on an Illumina NextSeq500, and DE genes with significant changes in expression were identified using the DESeq2 v1.38.0 bioinformatics tool under the strict detection criteria of |log2FC| ≥ 2 and adjusted p < 0.05. We identified 504 DE genes, which were enriched in terms related to “regulation of cell death”, “cation transport”, “response to topologically incorrect proteins”, and “response to unfolded proteins”. Surprisingly, these genes were involved in “the HSF1-dependent transactivation pathway” and “the attenuation phase pathway”. This bioinformatics-based study suggests that the tested fluorinated chalcone could influence HSF-1 silencing in addition to promoting the up-regulation of several genes involved in stress-induced apoptosis. Therefore, the tested compound could have enormous potential as a novel approach for TNBC treatment.

This study describes the efficient synthesis of five dinitrochalcones (DNCHs) using an ultrasonic bath as an unconventional method to improve reaction yields and reduce reaction times. The Claisen–Schmidt condensation of nitroacetophenones and nitrobenzaldehydes was carried out in a cyclohexane–methanol solvent system under ultrasonic irradiation, achieving yields between 56% and 92%. The application of ultrasound not only accelerated the reaction but also improved the overall efficiency compared to conventional methods such as magnetic stirring. The synthesized compounds were characterized by NMR spectroscopy, which corroborated their structures. Therefore, it is confirmed that obtaining DNCHs with a nitro group in ortho by ultrasonic irradiation is an energetically efficient and environmentally friendly alternative.

Organic synthesis plays a fundamental role in medicinal chemistry, allowing the production of compounds with desirable pharmacological properties. In this context, new synthesis methods, such as the use of ultrasound, are continuously being explored to improve the efficiency and sustainability of these processes. In this work, the synthesis and structural characterization of 2-nitrochalcone derivatives substituted with electron-withdrawing (fluoro) and electron-donating (methoxy) groups in the three isomeric positions of the B ring via nuclear magnetic resonance and ultrasound are presented; both a conventional method and a nonconventional ultrasound-assisted method are used. The results show that both methodologies are effective for obtaining these compounds, but the conventional method presents some additional advantages in the case of these nitrochalcones, such as shorter reaction times and better reaction yields.

This study describes the efficient synthesis of five dinitrochalcones (DNCH) using an ultrasonic bath as an unconventional method to improve reaction yields and reduce reaction times. The Claisen-Schmidt condensation of nitroacetophenones and nitrobenzaldehydes was carried out in a cyclohexane-methanol solvent system under ultrasonic irradiation, achieving yields between 56% and 92%. The application of ultrasound not only accelerated the reaction but also improved the overall efficiency compared to conventional methods such as magnetic stirring. Characterization of the synthesized compounds was performed by NMR spectroscopy, confirming the consistency of their structures. Thus, it is confirmed that obtaining DNCH with a nitro group in ortho provide by ultrasonic irradiation is an energetically efficient and environmentally friendly alternative.