Design, synthesis and bioactivity of a new class of antifungal amino acid-directed phthalide compounds.

BACKGROUND: Peanut southern blight disease, caused by Sclerotium rolfsii, is a destructive soil-borne fungal disease. The current control measures, which mainly employ succinate dehydrogenase inhibitors, are prone to resistance and toxicity to non-target organisms. As a result, it is necessary to explore the potential of eco-friendly fungicides for this disease. RESULTS: Fourteen novel phthalide compounds incorporating amino acid moieties were designed and synthesized. The in vitro activity of analog A1 [half maximal effective concentration (EC50) = 332.21 mg L-1] was slightly lower than that of polyoxin (EC50 = 284.32 mg L-1). It was observed that on the seventh day, the curative activity of A1 at a concentration of 600.00 mg L-1 was 57.75%, while the curative activity of polyoxin at a concentration of 300.00 mg L-1 was 42.55%. These results suggested that our compound exhibited in vivo activity. Peanut plants treated with A1 showed significant agronomic improvements compared to the untreated control. Several compounds in this series exhibited superior root absorption and conduction in comparison to the endothermic fungicide thifluzamide. The growth promotion and absorption-conduction experiments demonstrated the reason for the superior in vivo activity of the target compound. Cytotoxic assays have demonstrated that this series of targeted compounds exhibit low toxicity levels toward human lo2 liver cells. CONCLUSION: Our results provide a new strategy for the design and synthesis of novel green compounds. Furthermore, the target compound A1 can serve as a lead for further development of green fungicides. © 2024 Society of Chemical Industry.

Preparation of high electromagnetic interference shielding and humidity responsivity composite film through modified Ti3C2Tx MXene cross-linking with sodium alginate.

This paper established a new kind of L-citrulline-modified MXene cross-linked sodium alginate composite film through solution blending and casting film methods. The L-citrulline-modified MXene cross-linked sodium alginate composite film exhibited high electromagnetic interference shielding efficiency of 70 dB and high tensile strength of 7.9 MPa, which were much higher than the sodium alginate film without L-citrulline-modified MXene. In addition, the L-citrulline-modified MXene cross-linked sodium alginate film appeared humidity responsibility in a water vapor environment, the weight, thickness, and current appeared to increase trend and the resistance appeared to decrease trend after it absorbed water, and these parameters recovered to their original values after drying.

Low-driving-voltage, polarizer-free, scattering-controllable liquid crystal device based on randomly patterned photo-alignment.

In this work, a polarizer-free, electrically tunable liquid crystal device is presented. This device is based on randomly patterned photo-aligned boundaries generating light scattering in an adjacent liquid crystal film. Its transparent on state requires only 7.5Vrms driving voltage. Switching from a 49.5% hazy off state into the transparent on state occurs at 1.25 V, with only 1.2% residual haze. The effect exhibits fast rise and decay times of 0.3 ms and 7.2 ms, respectively. Thanks to its field-effect nature and the surface preparation process, zero ohmic low power consumption, fast response times, and steep transmission-voltage characteristics result. Applications are smart windows, light shutters, and/or transparent displays, as well as complementary metal-oxide-semiconductor driven multiplexed displays.

High Photoinduced Ordering and Controllable Photostability of Hydrophilic Azobenzene Material Based on Relative Humidity.

Azobenzene materials provide an effective way for liquid crystal (LC) alignment besides traditional rubbing technology. A strong relationship between relative humidity (RH) and the photoalignment quality of hydrophilic azobenzene dye brilliant yellow (BY) has been investigated. Good photoalignment quality can only be ensured at about 40% RH or below. On the other hand, the photostability of the alignment layer is also influenced dramatically by RH. The rewritability can be guaranteed at extremely low RH (≤10%). It is gradually lost with increasing RH, and the alignment layer becomes photostable against further light exposure when at 40% RH or above. Therefore, the BY photoalignment layer can be tuned from rewritable to photostable by simply adjusting RH, and thus multistep photopatterned alignments can be obtained and reserved based on this method. Similar properties are also expected for other hydrophilic azobenzene photoalignment materials, where the specific RH values may vary correspondingly. The reason is due to the strong intermolecular interaction and J-aggregate formation of BY molecules with water insertion. Moreover, the lyotropic LC formed by J-aggregated BY molecules in aqueous solution is reported here.

Exotic Property of Azobenzenesulfonic Photoalignment Material Based on Relative Humidity.

Azobenzene photoalignment materials are highly effective for liquid crystal alignment with high sensitivity and rewritability. A strong relationship between relative humidity and the alignment quality of a thin layer of azobenzenesulfonic dye has been investigated, where the photoinduced phase retardation, order parameter, and anchoring strength of the alignment layer are influenced dramatically by relative humidity. Our results provide fabrication guidance for the photoalignment process in both display and photonic applications. In addition, an exotic substantial ordering enhancement is observed by increasing the relative humidity without further light illumination, where the self-assembly of the photoaligned material incorporated with water molecules is the underlying reason for the enhanced high ordering (S > 0.8). Based on X-ray diffraction and depolarized optical microscopy observation, together with the photoalignment quality, a semicrystalline structure of the humidified azobenzenesulfonic material is proposed. The transition from amorphous solid at low relative humidity to semicrystal at high relative humidity provides a new perspective of understanding the hydrophilic photoalignment materials.