Thermoplastic polyurethanes (TPUs) bear tunable chemistry offering the possibility to develop a rich palette of physio‐mechanical properties, making the materials suitable for various fields of application. The great variety in TPUs properties comes from the choices of the monomers and the reaction conditions. Herein, the mechanical properties of the developed TPUs are tailored, while fine‐tuning the hard and soft segment molar ratio, as well as the reaction conditions. TPUs are synthesized from 4,4′‐methylenebis(phenyl isocyanate), poly(tetrahydrofuran), and 1,4‐butanediol, and their thermal and mechanical properties are fully characterized. The sample with the most appropriate mechanical properties that are suitable for catheter fabrication, is selected for the biomedical application. Quaternary ammonium salt is synthesized, and 0.5 mol% is incorporated in the TPU to confer antibacterial properties to the material while preserving its mechanical strength. The microbiological tests reveal the antibacterial effect of the developed materials against Staphylococcus aureus and Pseudomonas aeruginosa, as well as 80% SiHa cell viability, after 72 h of exposure, as part of the performed cytotoxicity studies. Finally, TPUs catheter prototypes fabrication is also proposed, applying an extrusion or injection molding approach for the production of biomedical devices with desirable mechanical properties.

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A new vobasine-tryptamine-based monoterpene indole alkaloid pseudodimer was isolated from the stem bark of Voacanga africana. As a minor constituent occurring in a thoroughly investigated plant, this molecule was targeted...

Voatriafricanines A and B (1 and 2), the first examples of vobasine-aspidosperma-aspidosperma monoterpene trisindole alkaloids, were isolated from the stem barks of Voacanga africana, guided by a molecular networking strategy. Their structures, including absolute configurations, were elucidated by spectroscopic methods and ECD calculations. Compounds 1 and 2 possess intramolecular hydrogen bonding, sufficiently robust to transfer homonuclear and heteronuclear magnetizations. Compound 1 exhibited potent antimycobacterial activity with no discernible cytotoxic activity.

We herein report on the first chemical assessment of Erythrococca anomala (Juss. ex Poir.) Prain (Euphorbiaceae), a genus that was – to the best of our knowledge – not studied yet from a phytochemical perspective. A molecular networking strategy was implemented to rapidly identify the known specialized metabolites from untargeted MS/MS analyses of E. anomala leaves ethanolic extract. This strategy allowed for the identification of diverse C-glycosyl flavones and a cursory examination of MS/MS spectra could extend the GNPS-provided annotation to pinpoint the structural novelty of further derivatives. The isolation of the sought-after structures could be streamlined based on MS-guidance and their structures, determined through extensive NMR analyses, displayed structural features in line with MS²-based predictions. Anticipating sharp structural features at an early stage of the dereplication process through a critical assessment of the tandem mass spectrometric landmarks was essential to embark on the isolation of the newly reported structures owing to the elevated number of flavonoid glycosides isomers thereof formerly known, which would have deterred us from isolating them without the support of additional tandem mass spectrometric information. The isolation of the main components of the ethanolic extract completed the currently provided chemical report on E. anomala, also resulting in the description of a new phenylethanoid derivative (3) and of a new orcinol-based dimer (4). Anomaloflavone (1) exhibit significant activities with minimal inhibitory concentration values of 25 µg/mL against Staphylococcus aureus and Mycobacterium smegmatis while failing to exert an antibacterial activity against Pseudomonas aeruginosa, while being devoid of cytotoxicity against SiHa cells.