New push–pull biphenyl-azopyrrole photoswitches are efficiently obtainedviaa Suzuki cross-coupling reaction, give rise to J-type aggregates in binary MeOH : H₂O solvents and undergo a water-assistedcis-to-transisomerization at room temperature.

We report the synthesis of a series of ferrocene amphiphilic donor–π–acceptor dyes, with the general formula (Fc-CHCH-HetNC₁₆H₃₃)⁺ X⁻ [where: Fc behaves as the donor group, a double bond as the π bridge, and 2-,4-pyridinium and 4-quinolinium as the potent acceptor groups (2a–b and 4, X = Br⁻ or BF₄ ⁻)], in good overall yields. Together with their neutral counterparts (6a–b and 7), the photophysical and electrochemical properties of these compounds were investigated by means of UV-Vis spectroscopy and cyclic voltammetry. The optical and electrochemical band gaps of these dyes were calculated, which indicated that 4 has the lowest bandgap value. Time-dependent DFT calculations indicate that the lowest energy absorption band displayed for these compounds has mainly metal-to-ligand charge transfer character, with the HOMO–LUMO electronic transition being the main contribution.

The design of new synthetic grafted poly(3-hydroxybutyrate) as composite 3D-scaffolds is a convenient alternative for tissue engineering applications. The chemically modified poly(3-hydroxybutyrate) is receiving increasing attention for use as biomimetic copolymers for cell growth. As of yet, these copolymers cannot be used efficiently because of the lack of good mechanical properties. Here, we address this challenge, preparing a composite-scaffold of grafted poly(3-hydroxybutyrate) polyurethane for the first time. However, it is unclear if the composite structure and morphology can also offer a biological application. We obtained the polyurethane by mixing a polyester hydroxylated resin with polyisocyanate and the modified polyhydroxyalkanoates. The results show that the poly(3-hydroxybutyrate) grafted with poly(vinyl alcohol) can be successfully used as a chain extender to form a chemically-crosslinked thermosetting polymer. Furthermore, we show a proposal for the mechanism of the polyurethane synthesis, the analysis of its morphology and the ability of the scaffolds for growing mammalian cells. We demonstrated that astrocytes isolated from mouse cerebellum and HEK293 can be cultured in the prepared material and express efficiently fluorescent proteins by adenoviral transduction. We also tested the metabolism of Ca²⁺ to obtain evidence of the biological activity.

A set of small benzothiadiazole (BTD)-based derivatives with a D–A–D architecture were synthesized and characterized as building blocks of organic semiconducting materials by applying an experimental–theoretical approach. The four derivatives tend to self-assemble into highly ordered crystalline solids, with varying degrees of responsiveness to mechanical and thermal stimuli. The featured derivatives exhibit absorption maxima in solution and molar extinction coefficient values related to π–π* electronic transitions with minor solvatochromic responses, displaying broad fluorescence profiles with large Stokes shifts and high fluorescence quantum yields. In the solid-state, the BTD derivatives display absorption maxima in the visible range and intense fluorescence emission of the n-butoxy and fluorene derivatives. The stability of the one-electron reduced and oxidized forms of all compounds was assessed by means of cyclic voltammetry, which complemented by DFT calculations allowed the identification of one BTD derivative (BuO-BTD) as a strong candidate for use as an electron transport layer in organoelectronic devices.