No abstract

A small library of carborane-BODIPY/aza-BODIPY dyads were efficiently synthesized by means of a novel convergent synthetic approach, the key step of which is a Pd-catalyzed Heck coupling reaction. The structural characterization and photoluminescence properties of the newly synthesized dyads were evaluated. The presence of the carborane did not significantly alter the photophysical patterns of the BODIPY or aza-BODIPY in the final fluorophores, but it produced a decrease of the emission fluorescent quantum yields that was in the range from 1.4 % for aza-BODIPY to 48 % for BODIPY-dyads. The carborane-BODIPY dyads were successfully incorporated into cells, especially compounds 2, 4 and 13, demonstrating their cytoplasmic localization. The fluorescent and biocompatibility properties make these compounds good candidates for in vitro cell tracking.

A small library of 2,6-and 3,5-distyrenyl-substituted carborane-BODIPY dyes was efficiently synthesized by means of a Pd-catalyzed Heck coupling reaction. Styrenyl-carborane derivatives were exploited as molecular tools to insert two carborane clusters into the fluorophore core and to extend the π-conjugation of the final molecule in a single synthetic step. The synthetic approach allows to increase the molecular diversity of this class of fluorescent dyes by the synthesis of symmetric or asymmetric units with enhanced boron content. The structural characterization and photoluminescence (PL) properties of synthesized dyes were evaluated. The developed compounds exhibit a significant bathochromic shift compared to their parent fluorophore scaffolds, and absorption and emission patterns were practically unaffected by the different substituents (Me or Ph) on the Ccluster atom (Cc) of the carborane cage or the cluster isomer (ortho-or metacarborane). Remarkably, the presence of carborane units at 2,6-positions of the fluorophore produced a significant increase of the emission fluorescent quantum yields, which could be slightly tuned by changing the Cc-substituent and the carborane isomer, as well as introducing ethylene glycol groups at the meso-position of 2 the BODIPY. All these features make these dyes promising candidates for further investigations in live-cell imaging and bio-supramolecular assays.

Laboratory evolved P450 BM3 A2 has an increased activity on the oxidation of high value terpenes. The oxidation of linalool into linalool oxide by P450 BM3 is shown for the first time.

Layered silicates (LS, clays) are a composite group of minerals whose industrial interest and technological applications are progressively expanding, spanning from catalysis to biomedicine. However, the compatibility of LS with biological systems is not clear, and mechanistic data about biophysicochemical interactions at the interface of LS and biomembranes are scarce. Here, cell membrane damage, assessed using red blood cells as model membranes, is revealed for kaolin (> 75 wt.% kaolinite, 1:1 layer structure) and bentonite (> 90 wt.% montmorillonite, 1:2 layer structure) particles. The high membranolytic capacity of bentonite (i.e., high ion‐exchanger LS) is the result of the combined contribution of both mineral surface features and sample‐specific cation exchange capacity (CEC). For kaolin (i.e., non‐ion‐exchanger LS), the capacity to damage membranes is primarily due to surface hydroxyl species, that is, silanols and aluminols, exposed at the crystal lattice boundaries. When kaolin is thermally disorganized into amorphous metakaolin, membrane damage is driven by a specific sub‐population of surface hydroxyl species, namely the “nearly free silanols”, previously evidenced on quartz. This study establishes the rationale underlying the interactions between LS particles and membranes and can set the basis for the understanding of interfacial phenomena of LS.