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Light-harvesting complexes in natural photosynthetic systems, such as those in purple bacteria, consist of photo-reactive chromophores embedded in densely packed “antenna” systems organized in well-defined nanostructures. In the case of purple bacteria, the chromophore antennas are composed of natural J-aggregates such as bacteriochlorophylls and carotenoids. Inspired by the molecular composition of such biological systems, we create a library of organic materials composed of densely packed J-aggregates in a polymeric matrix, in which the matrix mimics the optical role of a protein scaffold. This library of organic materials shows polaritonic properties which can be tuned from the visible to the infrared by choice of the model molecule. Inspired by the molecular architecture of the light-harvesting complexes of Rhodospirillum molischianum bacteria, we study the light–matter interactions of J-aggregate-based nanorings with similar dimensions to the analogous natural nanoscale architectures. Electromagnetic simulations show that these nanorings of J-aggregates can act as resonators, with subwavelength confinement of light while concentrating the electric field in specific regions. These results open the door to bio-inspired building blocks for metamaterials from visible to infrared in an all-organic platform, while offering a new perspective on light–matter interactions at the nanoscale in densely packed organic matter in biological organisms including photosynthetic organelles.

Optical Tamm states (OTS) are confined optical modes that can occur at the interface between two highly reflective structures. However, due to the strong reflectance required, their implementation with highly processable and metal-free flexible materials has proven challenging. Herein, we develop the first structure supporting OTS based only on organic polymeric materials, demonstrating a photonic platform based on non-critical, widely available and easily processable materials. The structures fabricated present large areas and consist of a narrowband multi-layered polymeric distributed Bragg reflector (DBR) followed by a thin film of J-aggregate molecular excitonic material that can act as a highly reflective surface within a narrowband range. We take advantage of the narrowband spectral response of the DBR and of the reflective molecular layer to tune the OTS band by varying the periodicity of the multilayer, opening the door for the fabrication of OTS structures based on lightweight integrable excitonic devices with cost-effective procedures.

Simple Summary: The occurrence of resistance to the standard treatment for estrogen receptor-positive (ER+) (Luminal A) breast cancer emphasizes the search for new molecules. In recent years, the interest in multi-target drugs has been growing, and they have even been identified as future therapeutic strategies. In line with this, this study aims to understand the anti-cancer action and multi-target potential of three new steroidal aromatase inhibitors (AIs): 7α-methylandrost-4-en-17-one (6), 7α-methylandrost-4-ene-3,17-dione (10a) and androsta-4,9(11)-diene-3,17-dione (13). We report new compounds that are able to impair the growth of sensitive and resistant ER+ breast cancer cells by acting as AIs, ER modulators and AR agonists, which is a therapeutic advantage over the current drugs applied in clinic. Therefore, this study is a breakthrough on drug discovery as it allows the discovery of new multi-target drugs for the treatment of ER+ breast cancer. Background/Objectives: Endocrine therapies that comprise anti-estrogens and aromatase inhibitors (AIs) are the standard treatment for estrogen receptor-positive (ER+) (Luminal A) breast cancer—the most prevalent subtype. However, the emergence of resistance restricts their success by causing tumor relapse and re-growth, which demands a switch towards other therapeutic approaches in order to minimize or overcome resistance. Indeed, this clinical limitation highlights the search for new molecules to improve cancer treatment. Recently, strategies that address multiple targets have been emerging, and multi-target drugs have the potential to become the future anti-cancer molecules. Our group has been searching for new multi-target compounds, and as part of this, our study aims to understand the anti-cancer and multi-target potential of three new steroidal aromatase inhibitors (AIs): 7α-methylandrost-4-en-17-one (6), 7α-methylandrost-4-ene-3,17-dione (10a) and androsta-4,9(11)-diene-3,17-dione (13). Methods: Their in vitro actions and molecular mechanisms were elucidated in a sensitive ER+ aromatase-overexpressing breast cancer cell line, MCF-7aro cells, as well as in an AI-resistant ER+ breast cancer cell line, LTEDaro cells. Results: All the new AIs (10 µM) prevented the proliferation of MCF-7aro cells by arresting cell cycle progression. Interestingly, all AIs (10 µM) act as androgen receptor (AR) agonists and modulate ER levels, synthesis and signaling to induce the apoptosis of ER+ breast cancer cells. Additionally, these new AIs (10 µM) also re-sensitize resistant cells by promoting apoptosis, offering a therapeutic benefit. Conclusions: Overall, new steroidal polypharmacological compounds have been discovered that, by acting as AIs, ER modulators and AR agonists, impair ER+ breast cancer cell growth. Overall, this study is a breakthrough on drug discovery as it presents new molecules with appealing anti-cancer properties and multi-target action for the treatment of ER+ breast cancer. [ABSTRACT FROM AUTHOR]

Background/Objectives: Côa Valley, located in the northeast of Portugal, harbors more than 500 medicinal plant species. Among them, four species stand out due to their traditional uses: Equisetum ramosissimum Desf. (hemorrhages, urethritis, hepatitis), Rumex scutatus L. subsp. induratus (Boiss. and Reut.) Malag. (inflammation, constipation), Geranium purpureum Vill., and Geranium lucidum L. (pain relief, gastric issues). Given their rich ethnomedicinal history, we evaluated their protective effects on an in vitro model of metabolic dysfunction-associated steatotic liver disease (MASLD). Methods: Decoction (D) and hydroalcoholic (EtOH80%) extracts were prepared and chemically characterized. Their safety profile and effects on lipid accumulation were assessed in palmitic acid (PA)-treated HepG2 cells using resazurin, sulforhodamine B, and Nile Red assays. Results: Chemical analysis revealed diverse phenolic compounds, particularly kaempferol derivatives in E. ramosissimum. All extracts showed minimal cytotoxicity at 25–50 µg/mL. At 100 µg/mL, only E. ramosissimum extracts maintained high cell viability. In the lipotoxicity model, E. ramosissimum decoction demonstrated the most potent effect, significantly reducing PA-induced neutral lipid accumulation in a dose-dependent manner, while other extracts showed varying degrees of activity. Conclusions: These findings highlight E. ramosissimum's decoction, rich in kaempferol derivatives, as particularly effective in reducing lipid accumulation in this MASLD cell model while also providing a comprehensive characterization of traditionally used plants from the Côa Valley region. [ABSTRACT FROM AUTHOR]

Amides are usually prepared using amines and acyl halides, which often implies a two-step procedure. Alternatively, coupling reagents can be used in a single-step reaction with good yields, which seems to be suitable for organic chemistry laboratory classes. This work was designed to synthesize "N"-hexylcinnamamide through a one-step reaction from cinnamic acid using the coupling reagent benzotriazol-1-yloxytri(pyrrolidino)phosphonium hexafluorophosphate (PyBOP). The purification of "N"-hexylcinnamamide, using various laboratory techniques, as well as its structural elucidation by spectroscopic methodologies, is also addressed. In addition, the theoretical partition coefficient (log "P") values of "N"-hexylcinnamamide and of cinnamic acid are predicted. The proposed experiment is developed in three laboratory classes and is planned for second-year undergraduate students. In summary, it is expected that students broaden their knowledge about amide synthesis, laboratory techniques, and spectroscopic characterization, especially IR and NMR. Besides the pedagogical enhancements, this activity also allows students to be in contact with research work based on the chemical modification of natural products according to a medicinal chemistry approach.