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Sequential optimization is one of the promising approaches in identifying the optimal candidate(s) (molecules, reactants, drugs, etc.) with desired properties (reaction yield, selectivity, efficacy, etc.) from a large set of potential candidates, while minimizing the number of experiments required. However, the high dimensionality of the feature space (e.g., molecular descriptors) makes it often difficult to utilize the relevant features during the process of updating the set of candidates to be examined. In this article, we developed a new sequential optimization algorithm for molecular problems based on reinforcement learning, multi-armed linear bandit framework, and online, dynamic feature selections in which relevant molecular descriptors are updated along with the experiments. We also designed a stopping condition aimed to guarantee the reliability of the chosen candidate from the dataset pool. The developed algorithm was examined by comparing with Bayesian optimization (BO), using two synthetic datasets and two real datasets in which one dataset includes hydration free energy of molecules and another one includes a free energy difference between enantiomer products in chemical reaction. We found that the dynamic feature selection in representing the desired properties along the experiments provides a better performance (e.g., time required to find the best candidate and stop the experiment) as the overall trend and that our multi-armed linear bandit approach with a dynamic feature selection scheme outperforms the standard BO with fixed feature variables. The comparison of our algorithm to BO with dynamic feature selection is also addressed. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: An amide‐substituted quinuclidine‐borane has been identified as a more efficient hydridic hydrogen atom transfer (HAT) catalyst for the hydroalkylation of unactivated olefins under visible‐light irradiation. 1H NMR titration experiments reveal that the amide moiety of the quinuclidine‐borane catalyst forms stronger hydrogen bonds with the carbonyl substrates, thereby improving the reaction yields. Furthermore, it was found that the reaction yields correlate well with the association constant between the quinuclidine‐borane catalyst and the carbonyl substrate. A scale‐up reaction using a continuous‐flow photoreactor has also been demonstrated. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: An amide‐substituted quinuclidine‐borane has been identified as a more efficient hydridic hydrogen atom transfer (HAT) catalyst for the hydroalkylation of unactivated olefins under visible‐light irradiation. 1H NMR titration experiments reveal that the amide moiety of the quinuclidine‐borane catalyst forms stronger hydrogen bonds with the carbonyl substrates, thereby improving the reaction yields. Furthermore, it was found that the reaction yields correlate well with the association constant between the quinuclidine‐borane catalyst and the carbonyl substrate. A scale‐up reaction using a continuous‐flow photoreactor has also been demonstrated. [ABSTRACT FROM AUTHOR]

This article introduces a new method in which tung oil is employed as a bio‐friendly curative substance enclosed within melamine‐urea‐formaldehyde microcapsules. Due to the high reactivity of melamine, particle agglomeration can occur. To tackle this issue, this study focuses on optimizing the quantity of emulsifiers to achieve the best microcapsules with 15% melamine in the shell structure without particle agglomeration. The impact of melamine content and the quantity of emulsifier on the morphology of the synthesized microcapsules, the reaction yield, core content, and the hardness of the microcapsule shell were investigated. The presence of tung oil in melamine‐urea‐formaldehyde microcapsules was proven by Fourier transform infrared spectroscopy (FT‐IR). Field emission scanning electron microscopy (FESEM) revealed the spherical morphology of the capsules with a mean diameter of 2.29 μm. UV–vis analysis and nano‐indentation tests were used to evaluate the core content and the hardness of the result microcapsules, respectively. Finally, one sample, as the best microcapsule, was dispersed in an alkyd‐based resin in the amount of 1, 2.5, and 5 wt% and applied on a steel substrate for its ability to prevent corrosion. The study also highlights the adverse effect of excessive capsule usage in the resin, as demonstrated by reduced resin adhesion to the substrate, according to electrochemical impedance spectroscopy (EIS) and salt spray tests. The study found that the best long‐term anticorrosion properties are achieved by including 1 wt% of microcapsules in an alkyd resin. [ABSTRACT FROM AUTHOR]

In the current study, we have developed an efficient and simple ultrasound-promoted protocol for synthesizing 2-methylthio-3H-1,5-benzodiazepine derivatives from α-oxo ketene dithioacetals using reusable CaFe2O4 nanoparticles as heterogeneous catalysts. The use of CaFe2O4 nanoparticles as catalyst under ultrasonic irradiation gave better yields in shorter reaction times in comparison to our previous synthetic strategy which used basic alumina as a solid support. The nanocatalyst was found to be applicable to diverse aromatic/heteroaromatic and cyclic ketones. In addition, the quantum mechanical calculations (DFT studies) of all the derivatives were carried out using Spartan software to determine the geometry and physiochemical properties of the derivatives and the molecular docking studies of all the optimized derivatives using Autodock Vina and Discovery Studio software to check their efficacy as antifungal agents. Based on the best docking results, In-vitro experimental studies of BDZ-13 and BDZ-19 were carried out to test their efficacy as antifungal agents. [ABSTRACT FROM AUTHOR]

Phosphate fertilization improves banana yields, but due to the physiological effects of phosphorus on plants, it can also be used to improve the physical and chemical characteristics of the fruits, which can contribute to increasing the processing of green bananas and reducing losses in the production chain. Herein, the productivity of bunches and fruit, the biometric analysis of the fruit, dry matter content, and the chemical composition of immature fruit were evaluated when the cultivar BRS SCS Belluna (AAA) was grown under different levels of phosphate fertilization for two harvest cycles. The results showed that phosphate fertilizer levels interfered with bunch yield and fruit mass in both cycles, leading to yield gains of 44.3% (1st cycle) and 84.0% (2nd cycle) in bunches and 51.8% (1st cycle) and 81.9% (2nd cycle) in fruits. Fertilization promoted gains of up to 33.5% in fruit mass and enhanced the resistant starch content in the pulp, leading to an increase of 15.1%. The phosphorus, potassium, and calcium contents in green fruits increased with fertilizer levels in the first cycle, improving nutritional quality. These results have useful applications because they indicate that adequate management of phosphate fertilization can increase the potential of the cultivar for industrial processing of green fruits and the nutritional quality of the derived products. [ABSTRACT FROM AUTHOR]

Fresh, nutritious, palatable produce for crew consumption on long-duration spaceflight missions may provide health-promoting, bioavailable nutrients and enhance the dietary experience. VEG-04A and VEG-04B explored growing leafy greens on the International Space Station using the Veggie Vegetable Production System. Two flight tests with ground controls were conducted in 2019 growing mizuna mustard, where Veggie chambers were set to different red-to-blue-to-green light formulations. Light quality affects plant growth, nutrition, microbiology, and organoleptic characteristics on Earth, and we examined how these vary in microgravity and under different harvest scenarios. Astronauts harvested and weighed mizuna and completed organoleptic evaluations. Flight samples were returned to Earth for nutritional quality and microbial food safety analyses. Yield and chemistry differed between ground and flight samples and light treatments, and bacterial and fungal counts were lower in ground than in flight samples. This research helps increase our understanding of the requirements for growing high-quality crops in spaceflight. [ABSTRACT FROM AUTHOR]

A series of small coinage metal(I) clusters has been selectively synthesized using 2-(diphenylphosphino)-1,10-phenanthroline (L), a new promising dimetal-binding P,N,N′-ligand (L). Its reaction with CuI yields the complex [Cu2L2(μ2-I)]2[Cu2I4], while the treatment of L with Au(tht)Cl/Ag+ or Au(tht)Cl/Cu+ systems leads to the assembly of [Au2AgL2Cl2]+, [Au2CuL2Cl2]+, [CuAuL2]2+ and [AgAuL2]2+ clusters. Theoretical analysis revealed pronounced intermetallic close shell interactions in these di- and trinuclear ensembles. At 298 K, the title compounds exhibit an orange and near-infrared (NIR) phosphorescence with lifetimes of 0.344–38 μs and quantum efficiencies of 1–21%. Theoretical considerations suggest a 3(M+L)LCT type for the observed phosphorescence. In addition, the above clusters exhibit a strong dose-dependent cytotoxic effect on A549, HepG2, Hep2 and MRC5 human cells with IC50 values ranging from 1.26 to 11.1 μM. [ABSTRACT FROM AUTHOR]

Herein, gold nanoparticle-decorated amorphous carbon (Au/AC) was prepared by reducing chloroauric acid and layering it on amorphous carbon. The characteristics of Au/AC were examined using FT-IR, XRD, TGA, SEM, EDS, and XPS. To assess its catalytic activity, Au/AC was tested in a reaction involving anthranilamide and benzyl alcohol at 110 °C for 24 hours. This reaction yielded various 2-phenylquinazolin-4(3H)-one derivatives in moderate to good yields (44–80%). Furthermore, control experiments were conducted to demonstrate the oxidation and cyclization functions of Au/AC. Noteworthy aspects of this approach included the ease of isolating Au/AC (via recrystallization) and the ability to recycle it. [ABSTRACT FROM AUTHOR]

The current study aimed to investigate the effects of plant-mediated selenium nanoparticles (SeNPs) on plant growth, photosynthetic pigments, antioxidant activity, and the triacylglycerol profile of sesame (Sesamum indicum L.). The green synthesis of SeNPs was achieved using garlic extract, resulting in spherical nanoparticles with an average size range of 70–75 nm. Three SeNP treatments (T3, 30 ppm; T4, 40 ppm; and T5, 50 ppm) were applied through seed and foliar spray on six sesame varieties (V1, TS-5; V2, TH-6; V3, Til-18; V4, Niab Millennium; V5, Niab Pearl; and V6, NS-16). All enzymatic antioxidant parameters showed an increase in the treated groups, such as SOD (74.4% in V1 at T4), POD (43% in V5 at T5), APX (62% in V1 at T3), and GPX (31.56% in V3 at T4). CAT showed the highest percentage improvement in T5 for V1, V2, V4, and V5, while V3 and V4 exhibited the highest values at T4. Likewise, seed antioxidant parameters also showed increase in antioxidant activity, highest total phenolic content (6.06 mg GAE/g) was found at T5 treatment with percent increase of 27.41%, but the highest percent increase was found to be at T4 treatments in V1 with increase of 46.83%. Percent oil yield was also noted to be higher as highest percent (60%) oil yield was obtained at T4 treatment in V3. Ultra High Performance Mass-Spectrometry (UHPLC-MS) analysis and chemometric modeling suggested a total of 10 triacylglycerol (TG) biomarkers separating untreated groups, with higher relative abundance values at T4 and T5 treatments compared to control. PCA and correlation analysis showed clustering of untreated groups from T4 and T5, which suggests that these two treatments result in higher accumulation of oil. A generalized linear model with ANOVA showed a highly significant impact of treatments on all the growth and oil parameters, with significance involvement of varieties. The interaction between variety and treatment showed no significant effect on the growth and oil biomarkers of sesame. However, it can be concluded that the T4 and T5 treatments (40 ppm and 50 ppm) of SeNPs, applied through seed and foliar methods, have a strong influence on the overall growth and oil yield of sesame. This warrants further transcriptomic and molecular analysis to gain deeper insight into the mechanisms of action of SeNPs. [ABSTRACT FROM AUTHOR]

ABSTRACT Surface enhanced Raman scattering (SERS) is a widely used vibrational spectroscopic technique employing metallic nanostructures to enhance an inherent Raman signal. This study aimed to develop a method for the characterization of SERS substrates in a single analysis by inductively coupled plasma mass spectrometry (ICP‐MS) equipped with the single particle module (spICP‐MS). For this development, the well‐known Lee‐Meisel protocol was selected as starting point to synthesize gold nanoparticles (AuNps) and silver nanoparticles (AgNps). A spICP‐MS method was successfully developed and gave the mean size, size distribution, and concentration of nanoparticles in only one single analysis. Reference techniques were used to confirm these results namely dynamic light scattering, transmission electron microscopy, and UV–Visible spectroscopy. Thanks to the ICP‐MS characterization, it was observed that AgNps synthesized by chemical reduction presented more variability than the AuNps. The dissolved elements concentration in the suspension was investigated. It appeared that reaction yields were close to 100% for the six syntheses. This analysis may be repeated over time to evaluate the suspension stability and monitor any potential degradation of Nps. To conclude, ICP‐MS is a powerful technique to characterize SERS substrates and could be an interesting alternative to other characterization techniques. [ABSTRACT FROM AUTHOR]

Fluorophores are essential tools for optical imaging and biomedical research. Their synthetic modification to incorporate new functions, however, remains a challenging task. Conventional strategies rely on linear synthesis in which a parent framework is gradually extended. We here designed and synthesized a versatile library of multi‐functional fluorophores via a scaffold‐based Ugi four‐component reaction (U‐4CR). The adaptability of the scaffold is achieved through modification of starting materials. This allows to use a small range of starting materials for the creation of fluorogenic probes that can detect reactive‐oxygen species and where the localization into subcellular organelles or membranes can be controlled. We present reaction yields ranging from 60 % to 90 % and discovered that some compounds can even function as imaging and therapeutic agents via Fenton chemistry inducing pyroptosis in living cancer cells. Our study underlines the potential of scaffold‐based synthesis for versatile creation of functional fluorophores and their applications. [ABSTRACT FROM AUTHOR]

Efficient photocatalytic CO2 reduction coupled with the photosynthesis of pure H2O2 is a challenging and significant task. Herein, using classical CO2 photoreduction site iron porphyrinate as the linker, Ag(I) clusters were spatially separated and evenly distributed within a new metal–organic framework (MOF), namely Ag27TPyP‐Fe. With water as electron donors, Ag27TPyP‐Fe exhibited remarkable performances in artificial photosynthetic overall reaction with CO yield of 36.5 μmol g−1 h−1 and ca. 100 % selectivity, as well as H2O2 evolution rate of 35.9 μmol g−1 h−1. Since H2O2 in the liquid phase can be more readily separated from the gaseous products of CO2 photoreduction, high‐purity H2O2 with a concentration up to 0.1 mM was obtained. Confirmed by theoretical calculations and the established energy level diagram, the reductive iron(II) porphyrinates and oxidative Ag(I) clusters within an integrated framework functioned synergistically to achieve artificial photosynthesis. Furthermore, photoluminescence spectroscopy and photoelectrochemical measurements revealed that the robust connection of Ag(I) clusters and iron porphyrinate ligands facilitated efficient charge separation and rapid electron transfer, thereby enhancing the photocatalytic activity. [ABSTRACT FROM AUTHOR]

Efficient photocatalytic CO2 reduction coupled with the photosynthesis of pure H2O2 is a challenging and significant task. Herein, using classical CO2 photoreduction site iron porphyrinate as the linker, Ag(I) clusters were spatially separated and evenly distributed within a new metal–organic framework (MOF), namely Ag27TPyP‐Fe. With water as electron donors, Ag27TPyP‐Fe exhibited remarkable performances in artificial photosynthetic overall reaction with CO yield of 36.5 μmol g−1 h−1 and ca. 100 % selectivity, as well as H2O2 evolution rate of 35.9 μmol g−1 h−1. Since H2O2 in the liquid phase can be more readily separated from the gaseous products of CO2 photoreduction, high‐purity H2O2 with a concentration up to 0.1 mM was obtained. Confirmed by theoretical calculations and the established energy level diagram, the reductive iron(II) porphyrinates and oxidative Ag(I) clusters within an integrated framework functioned synergistically to achieve artificial photosynthesis. Furthermore, photoluminescence spectroscopy and photoelectrochemical measurements revealed that the robust connection of Ag(I) clusters and iron porphyrinate ligands facilitated efficient charge separation and rapid electron transfer, thereby enhancing the photocatalytic activity. [ABSTRACT FROM AUTHOR]

Efficient photocatalytic CO2 reduction coupled with the photosynthesis of pure H2O2 is a challenging and significant task. Herein, using classical CO2 photoreduction site iron porphyrinate as the linker, Ag(I) clusters were spatially separated and evenly distributed within a new metal–organic framework (MOF), namely Ag27TPyP‐Fe. With water as electron donors, Ag27TPyP‐Fe exhibited remarkable performances in artificial photosynthetic overall reaction with CO yield of 36.5 μmol g−1 h−1 and ca. 100 % selectivity, as well as H2O2 evolution rate of 35.9 μmol g−1 h−1. Since H2O2 in the liquid phase can be more readily separated from the gaseous products of CO2 photoreduction, high‐purity H2O2 with a concentration up to 0.1 mM was obtained. Confirmed by theoretical calculations and the established energy level diagram, the reductive iron(II) porphyrinates and oxidative Ag(I) clusters within an integrated framework functioned synergistically to achieve artificial photosynthesis. Furthermore, photoluminescence spectroscopy and photoelectrochemical measurements revealed that the robust connection of Ag(I) clusters and iron porphyrinate ligands facilitated efficient charge separation and rapid electron transfer, thereby enhancing the photocatalytic activity. [ABSTRACT FROM AUTHOR]

Efficient photocatalytic CO2 reduction coupled with the photosynthesis of pure H2O2 is a challenging and significant task. Herein, using classical CO2 photoreduction site iron porphyrinate as the linker, Ag(I) clusters were spatially separated and evenly distributed within a new metal–organic framework (MOF), namely Ag27TPyP‐Fe. With water as electron donors, Ag27TPyP‐Fe exhibited remarkable performances in artificial photosynthetic overall reaction with CO yield of 36.5 μmol g−1 h−1 and ca. 100 % selectivity, as well as H2O2 evolution rate of 35.9 μmol g−1 h−1. Since H2O2 in the liquid phase can be more readily separated from the gaseous products of CO2 photoreduction, high‐purity H2O2 with a concentration up to 0.1 mM was obtained. Confirmed by theoretical calculations and the established energy level diagram, the reductive iron(II) porphyrinates and oxidative Ag(I) clusters within an integrated framework functioned synergistically to achieve artificial photosynthesis. Furthermore, photoluminescence spectroscopy and photoelectrochemical measurements revealed that the robust connection of Ag(I) clusters and iron porphyrinate ligands facilitated efficient charge separation and rapid electron transfer, thereby enhancing the photocatalytic activity. [ABSTRACT FROM AUTHOR]

Phenol Schiff bases can conveniently be prepared in high yield by the reaction of the appropriate aminophenols and aldehydes in solventless condition. The final target compounds were characterized by FT‐IR, 1HNMR, 13CNMR, and Mass spectroscopy. Microwave assistance reduced the reaction time and solvent, increased the yield, purity, and eased the work up. The compounds were found to possess moderate to good antibacterial activity implying that the synthesized compounds may make excellent candidates for further studies aimed at discovering novel antibacterial agents. In vitro antioxidant qualities of the synthesized Schiff bases are also evaluated. In the tests for reducing power and radical scavenging, all the compounds demonstrated strong antioxidant activity even surpassing that of the positive control, Trolox. [ABSTRACT FROM AUTHOR]

AbstractHybrid compounds are synthetic scaffolds of two or more pharmacophores that can be recognized as important reagents to increase the desired activity of biologically active compounds. This investigation develops an efficient and successful procedure for the synthesis of hybrid compounds based on 1,2,3-triazole scaffolds. Hybrid compounds include benzimidazole linked-1,2,3-triazole 9a-d and thiazolo[3,2-a] benzimidazole linked-1,2,3-triazoles 10a-d prepared from acetylenic benzimidazoles and substituted iodophenyl-1,2,3-triazoles with 75-90% yields, through Sonogashira coupling and heteroannulation. The reactions were carried out in DMF as the solvent and catalyzed by palladium(II) acetate/copper(I) iodide, in the presence of morpholine as an effective base at 70 °C. One-pot reaction conditions, high reaction yields, and simple reaction procedures are the advantages of this method. [ABSTRACT FROM AUTHOR]

Octacalcium phosphate (OCP) is a fascinating calcium phosphate material with a layered structure that can incorporate various guest molecules, particularly dicarboxylate ions. However, the solution-phase synthesis of OCP fine particles is challenging. In this study, we developed a new precipitation method based on the LaMer model for synthesising fine particles of plain OCP and OCP with incorporated isophthalate and succinate ions. Highly concentrated aqueous solutions and appropriate reaction conditions yielded particle sizes of 100–200 nm for plain OCP and 200–300 nm for OCP with incorporated dicarboxylate ions. The obtained particle sizes were significantly smaller than those of OCPs synthesised using conventional methods. The incorporation of isophthalate and succinate ions into OCP was confirmed using various methods, particularly X-ray diffraction, which revealed expansion of the (100) interplanar spacing. During the synthesis of OCP with incorporated isophthalate ions, hydrolysis of the OCP phase was minimised when the initial pH range of the isophthalic acid solution was 5.2–5.3. Interestingly, OCP with incorporated isophthalate ions exhibited fluorescence (excitation and emission at 325 and 390 nm, respectively), demonstrating the potential of these fine particles as novel biofriendly fluorescent probes. This novel LaMer-model-based synthesis for preparing fine particles of OCP and OCP with incorporated functional carboxylate ions can contribute to the design and development of next-generation biofriendly imaging probes and other functional calcium phosphate materials, such as for use in biosensing and drug delivery applications. [ABSTRACT FROM AUTHOR]

The interest in the applications of upconverting luminescent nanomaterials has expanded significantly, particularly in the biomedical field. An opportunity for innovation in this realm lies in the development of multimodal contrast agents that exhibit both luminescent and magnetic responses. This study presents an easily reproducible strategy for the solvothermal synthesis of NaYF 4 :Yb3+,Ln3+@NaGdF 4 (Ln = Er3+ or Tm3+) core@shell nanoparticles. The shell incorporation process initially involved dissolving the outer layer of NaYF 4 :Yb3+,Ln3+ cores, followed by the radial growth of NaGdF 4 around them. This shell provides intense paramagnetic properties without affecting the luminescent response of the cores. The optimized process yielded individual core@shell nanoparticles, with average diameters of 20 ± 5 nm for NaYF 4 :Yb3+,Er3+@NaGdF 4 and 19 ± 3 nm for NaYF 4 :Yb3+,Tm3+@NaGdF 4 UCNPs. The presence of NaGdF 4 shells was further confirmed by Raman spectroscopy, which revealed a change in polarizability within the structure due to the presence of Gd3+ instead of Y3+. Based on the hysteresis loops, the magnetic response of NaYF 4 :Yb3+,Ln3+ was negligible, whereas NaYF 4 :Yb3+,Ln3+@NaGdF 4 exhibited saturation at 1.04 emu/g at 20 kOe. Compared to common thermal decomposition approaches, this method offers several advantages: it provides nanoparticles that are colloidally stable in aqueous solutions, a higher reaction yield, eliminates the need for an inert atmosphere, reduces the excessive use of solvents for separation and washing, and requires less experimental manipulation. Therefore, this method enables the synthesis of materials with applications in the development of sensors, contrast agents, or theranostic tools with dual magnetic-luminescent responses. [ABSTRACT FROM AUTHOR]

Metal-based catalysts play an essential role in organic chemistry and the chemical industry. This research designed and successfully synthesized a pillar-layered metal–organic framework (MOF) with the urea linkers, namely Basu-HDI, as a novel and efficient heterogeneous catalyst. Various techniques such as FT-IR, EDX, elemental mapping, SEM, XRD, BET, and TGA/DTA studied its structure and morphology. Then, we investigated the synthesis of new 1,8-naphthyridines utilizing Basu-HDI in mild conditions via a one‐pot, three‐component tandem Knoevenagel/Michael/ cyclization/anomeric-based oxidation reaction. Final products were achieved by anomeric-based oxidation without employing an oxidation agent. Remarkably, this tandem process gave a good range of new 1,8-naphthyridines with high yields in a short reaction time. The pure products were confirmed by FT-IR, 1H NMR, 13C NMR, and mass spectrometry techniques. Moreover, the introduced catalyst showed good efficiency and stability and can be reused four times without significantly reducing efficiency. [ABSTRACT FROM AUTHOR]

We describe here an immobilization method of four Keggin‐type polyoxometalates (POMs) ([H2W12O40]6−, [BW12O40]5− [SiW12O40]4−, [PW12O40]3−) by using the reaction with an ionic liquid, 1‐butyl‐3‐vinylimidazolium (BVIM) bromide. The reaction yields a hybrid material (BVIM‐POM) as a water‐insoluble salt. The chemical structure of both compounds is preserved, as indicated by infrared spectroscopy (FT‐IR), although with a reduced crystallinity (shown by X‐ray diffraction analysis) due to a decrease of water content (shown by thermogravimetric analysis). Cross polarization 1H‐31P NMR evidenced the presence of BVIM in the structure of (BVIM)3[PW12O40]. The salt is mixed with carbon powder and Nafion to prepare an ink and casted on glassy carbon electrodes. The electrochemical behavior of immobilized POMs material is preserved. The electrochemical activity for nitrite reduction is measured by cyclic voltammetry and differential electrochemical mass spectrometry (DEMS). It was observed that the reduction current of 10 mM HNO2 at pH 1 in 0.5 M Na2SO4 is enhanced in the presence of these hybrid materials. DEMS has evidenced the formation of nitrous oxide (N2O) at potentials more positive compared to the use of parent POMs in solution. [ABSTRACT FROM AUTHOR]

To clarify the influence of H2O thermal effect on the formation of ultrafine particulate matter (PM), Huangling coal char was burned in a high-temperature drop tube furnace at 1800 K under various O2/N2/H2O and O2/N2/H2O/Ar atmospheres. The introduction of Ar in the simulating atmosphere was designed to counteract the thermal effect of H2O. Results indicated that after eliminating the thermal effect of H2O, the yield of ultrafine PM continuously increased in higher H2O content. Compared with no H2O, the mass and number yield of ultrafine PM in O2/N2/H2O/Ar atmosphere with 30% H2O content increased by 35.5% and 58.9%, respectively. H2O thermal effect, gasification reaction, and char oxidation reaction during coal char combustion played a significant role in the formation of ultrafine PM. Oxidation reaction was the primary factor affecting the formation of ultrafine PM, and its relative contribution was more than 62.9%, whereas the thermal effect of H2O showed an overall negative net effect on the formation of ultrafine PM. With the H2O content varied from 5% to 30%, the contribution of H2O thermal effect to mass yield was in the range of −19.1% to −18.0%, while that to number yield was −33.1% to −30.6%. Once the H2O content reached 10%, the enhancing effect of H2O gasification reaction on the yield of ultrafine PM surpassed the negative contribution of H2O thermal effect. For a given H2O content, elevated O2 concentration weakened the negative contribution of H2O thermal effect. [ABSTRACT FROM AUTHOR]

A series of 6 novel ester derivatives 2–7 of natural product geodin 1 were designed and semi-synthesized through one mild step reaction with high yield. Compounds 2–7 showed strong inhibitory activities against Staphylococcus aureus in the range of 2.35–9.41 μM. Compounds 4 and 7 showed very strong inhibitory activities against antifouling bacteria Aeromonas salmonicida with MICs of 2.42 μM and 4.56 μM respectively. Most notably compounds 3–7 showed potent antifungal activities against Candida albicans in the range of 0.59–2.44 μM. Particularly, compound 3 showed the highest antifungal activity against C. albicans with a MIC value of 0.59 μM. The preliminary structure activity relationship of these derivatives showed that replacement of 4-OH group with benzoyl substituents could enhance the antibacterial and antifungal activities of geodin 1. [ABSTRACT FROM AUTHOR]

The epigenetic reader SntB was identified as an important transcriptional regulator of growth, development, and secondary metabolite synthesis in Aspergillus flavus. However, the underlying molecular mechanism is still unclear. In this study, by gene deletion and complementation, we found SntB is essential for mycelia growth, conidial production, sclerotia formation, aflatoxin synthesis, and host colonization. Chromatin immunoprecipitation sequencing (ChIP-seq) and RNA sequencing (RNA-seq) analysis revealed that SntB played key roles in oxidative stress response of A. flavus, influencing related gene activity, especially catC encoding catalase. SntB regulated the expression activity of catC with or without oxidative stress, and was related to the expression level of the secretory lipase (G4B84_008359). The deletion of catC showed that CatC participated in the regulation of fungal morphogenesis, reactive oxygen species (ROS) level, and aflatoxin production, and that CatC significantly regulated fungal sensitive reaction and AFB1 yield under oxidative stress. Our study revealed the potential machinery that SntB regulated fungal morphogenesis, mycotoxin anabolism, and fungal virulence through the axle of from H3K36me3 modification to fungal virulence and mycotoxin biosynthesis. The results of this study shed light into the SntB-mediated transcript regulation pathways of fungal mycotoxin anabolism and virulence, which provided potential strategy to control the contamination of A. flavus and its aflatoxins. [ABSTRACT FROM AUTHOR]

The compound 1,3-diphenyl-1H-pyrazole-4-carbaldehyde (1) was utilized as a fundamental component in the synthesis of novel N-phenyl pyrazole derivatives. Substituted N-phenyl pyrazole compounds including 2-cyano-3-(1,3-diphenyl-1H-pyrazol-4-yl)-N-Substituted-acrylamide derivatives (4a–h), 4-(hydrazineylidenemethyl)-1,3-diphenyl-1H-pyrazole (6) and 2-cyano-N'-((1,3-diphenyl-1H-pyrazol-4-yl)methylene)-acetohydrazide (11) were obtained in moderate yields through the reaction of 1 with 2-cyano-N-substituted acetamide derivatives 3a–h, hydrazine hydrate, and cyanoacetohydrazide under basic-catalyzed conditions, respectively. Moreover, hydrazinyl-pyarzole 6 reacted with 4,5,6,7-tetrabromoisobenzofuran-1,3-dione (7) to afford 4,5,6,7-tetrabromo-2-(((1,3-diphenyl-1H-pyrazol-4-yl)methylene)amino)- isoindoline-1,3-dione (8). Furthermore, pyrazoloacetohydrazide 11 is condensed with salicylaldehyde derivatives 12a–e to give pyrazolochromene carbohydrazide derivatives 13a–e. Also, acetohydrazide 11 refluxed with N, N-dimethylformamide dimethyl acetal to produce 2-cyano-3-(dimethylamino)-N'-((1,3-diphenyl-1H-pyrazol-4-yl)methylene)acrylohydrazide (15), which upon exposure to acidic conditions underwent cyclization to form 4-((dimethylamino)methylene)-6-(1,3-diphenyl-1H-pyrazol-4-yl)pyridazine-3,5(4H,6H)-dione (16). The newly synthesized compounds were identified and confirmed using elemental and spectral data analyses as IR, MS, 1H NMR, 13C NMR, and 2D NMR analysis (H-H COSY, HSQC, HMBC, and NOSEY), Also, DFT studies were done to prove the geometrical optimization and spatial distributions orbitals of compounds 4a and 11. The toxicity of N-phenylpyrazole compounds was tested against the corn leaf aphid (Rhopalosiphum maidis) and the mealy plum aphid (Hyalopterus pruni). Compounds 4c, 13c, and 13d were found to be the most potent to control the two insects compared with acetamiprid 20% SP recommended by the Ministry of Agriculture. The biochemical investigation of insects was studied to the most effective compounds on insects as well, and the toxicity of compounds 4c, 13c, and 13d was studied on the predators (Hippodamia variegata, Cydonia vicina isis, Cydonia vicina nilotica, and 4th instar larvae H. variegata) under laboratory conditions. [ABSTRACT FROM AUTHOR]

A method of 90Sr determination in natural waters was tested in this study. The method included the steps of strontium preconcentration by a carbonate-containing zirconium hydroxide (Termoxid-3 K), strontium stripping with 1 M HCl and preparation of a counting source, followed by its measurement using a low background alpha/beta radiometer UMF-2000. Using the described method, we have determined activity concentrations of 90Sr in 16 samples of natural water collected at the territories of Sverdlovsk region and Chelyabinsk region (Middle Urals, Russia) as well as 8 samples from observing wells at a radioactive waste storage facility and 3 samples from observing wells at a point of radioactive waste final disposal. The dependence of strontium chemical yield in the method on calcium concentration and water hardness was determined. It was shown that strontium chemical yield was constant (81 ± 2%) for natural waters with a hardness less than 5.2 mmol/L and calcium concentration less than 76 mg/L; thus, a control of strontium chemical yield is not necessary for such water samples. A decrease of strontium chemical yield to 66.5 ± 1.5% was observed at higher calcium concentrations up to 178 mg/L. The method provided a minimum detectable activity of 90Sr as low as 0.02 Bq/L. [ABSTRACT FROM AUTHOR]

We report a unique synthetic route to benzo[7]annulene derivatives. When benzylidene malonates having a 1-(N , N -dialkylamino)alkyl group at the ortho -position are treated with a stoichiometric amount of M(OTf)3 (M = Sc, Yb, Gd), three transformations ([1,4]-hydride shift/isomerization into an enamine/intramolecular Stork enamine acylation) proceed sequentially to afford various benzo[7]annulene derivatives in moderate chemical yields. To our knowledge, the present reaction is the first example of an internal redox reaction involving a [1, n ]-hydride shift/(n +3)-cyclization process. [ABSTRACT FROM AUTHOR]

For systematic monitoring of radioactive nuclides in marine products, this study aimed at streamlining and simplifying the analysis method for the prominent radioisotope, strontium-90 (90Sr). The DGA chelate solid-phase extraction technique was employed for enhanced efficiency. The study focused on optimizing the necessary pretreatment procedures while minimizing the steps involving HNO3 leaching. This protocol enabled the quantitative recovery of strontium, and it facilitated a rapid analysis without the need for a time-consuming evaporation step and without waiting for secular equilibrium between 90Sr and its progeny to be reached. The method incorporating the optimized pretreatment protocol was applied to three diverse marine fish species and the accurate quantification of 90Sr at background levels in surface seawater was achieved. The method obtained concentrations in bone samples from these species that ranged from 0.036 to 0.120 mBq per kg-dry, and chemical yield values were notably high, ranging from 87.7% to 92.5%. [ABSTRACT FROM AUTHOR]

Fricke gel dosimeters are appropriate candidates for gamma dosimetry. Polyvinyl alcohol Fricke gel dosimeters are the most recent introduced gel dosimeters which have low ion diffusion. In this work, samples of ferrous-xylenol orange-polyvinyl alcohol gel dosimeters were prepared and characterized using optical spectroscopy. Using win XCOM program and the elemental composition of the gel, the mass attenuation coefficients for photons were evaluated. The results exhibited that the prepared gel is the nearly radiological blood-, soft tissue- and water-equivalent. The 60Co gamma cell unit was used to irradiate the gel samples. A dose range response was found linear from 10 to 30 Gy and suitable for blood irradiation dosimetry. Additionally, the gel response good repeatability was confirmed by the coefficient of variation calculations. Furthermore, chemical yield of the gel was estimated to be 34.6. The good characteristics of the prepared gel make it appropriate for dosimetry of blood irradiators. [ABSTRACT FROM AUTHOR]

Chemically initiated oxidative polymerization stands out as the most suitable method for the large‐scale and controllable synthesis of perfluoropolyether (PFPE). However, the mechanism and related reaction kinetics of this synthesis reaction remain elusive. In this study, PFPE was synthesized through the copolymerization of hexafluoropropylene and oxygen, initiated by fluorine. Subsequently, the synthesis mechanism of this chemically initiated oxidative polymerization was first explored using density functional theory. Simulation results yielded a comprehensive reaction network of the synthesis process, including chain initiation, propagation, decomposition, transfer, and termination. Meanwhile, a detailed kinetic model was constructed based on theoretical reaction rates of relevant elementary reactions. The effects of reaction operating conditions on the molecular weight of PFPE were experimentally investigated, with results in good agreement with the kinetic model. This work stablishes a solid foundation for optimizing and controlling the PFPE synthesis process. [ABSTRACT FROM AUTHOR]

We report a synthesis of the trans and cis isomers of 1,4‐di‐tert‐butyl‐2,2,3,3,5,5,6,6‐octamethyl‐1,4‐diphenylcyclohexasilane (3), together with the solid‐state structure of cis‐3. Both isomers were characterized using multinuclear NMR and UV spectroscopies and were compared based on these data, together with DFT calculations. Remarkably, we found that both isomers of 3 showcase redshifted UV maxima when compared with other known cyclosilanes. To explain this, the theoretical calculations show that the transitions involved in the excited states of trans‐3 and cis‐3 have, in addition to the expected σ conjugation component of the Si6 ring, significant π contributions of phenyl substituents. The results presented herein show the effect of the substituent's electronic properties regarding reactivity of intermediates, reaction yield, identity, and electronic properties of novel silicon‐containing molecules. [ABSTRACT FROM AUTHOR]

Lithium (Li) metal anodes have received sustained attention due to their remarkable theoretical specific capacities and low electrochemical potentials. However, the nucleation and growth of Li dendrites during cycling have hindered their application in Li metal batteries (LMBs). As an indispensable battery component, separators offer an ideal platform for mitigating Li dendrites. Herein, an ion‐management membrane (IMM) concept utilizing polydopamine (PDA)‐modified polyetherimide track‐etched membranes (PEITEMs) is proposed. The PDA@PEITEM‐based IMM features vertically aligned uniform electronegative nanochannels, serving as ion distributors and "Li‐ion guides" to simultaneously smooth ion concentration fluctuations and accelerate Li+ selective conduction. The IMM's unique structural and chemical properties yield exceptional ionic conductivity (0.73 mS cm−1) and high Li+ transfer number (0.80) while minimizing Li+ concentration fluctuations. When employed in Li/Cu cells, the IMM facilitates a Coulombic efficiency exceeding 96% over 100 cycles at 0.5 mA cm−2. Moreover, it extends the cycle lifespan of Li/Li cells to 1 200 h at 1.0 mA cm−2. For Li/LiFePO4 cells, this approach enables a specific capacity of 146 mAh g−1, maintaining capacity retention of 79.84% after 1 000 cycles. This novel strategy for constructing free‐standing functional separators is convenient, efficient, and scalable, providing valuable insights into multifunctional separators for dendrite‐free LMBs. [ABSTRACT FROM AUTHOR]

The glycolysis of PET represents a pivotal approach to achieving high-value utilization following its disposal. However, an efficient and cost-effective catalyst is required. This study reports on the use of a titanium isophthalate (Ti-IPA) catalyst for PET depolymerization. Ti-IPA was prepared using isophthalic acid and titanate as raw materials via a one-pot method. The study investigated the effects of different titanium sources and solvent types on Ti-IPA. The optimal conditions for the glycolysis reaction were determined using response surface methodology, and the 0.86% Ti-IPA catalyst provided a BHET yield of 84.86% for a reaction lasting 3.15 h at 194 °C with 12.8 mL ethylene glycol. Finally, a comparative analysis of the catalytic performance of Ti-IPA revealed that it is a promising novel catalyst with significant commercial potential. [ABSTRACT FROM AUTHOR]

Natural compounds are widely incorporated into cosmetic products for many purposes. Diterpenes often function as fragrances, enhancing the sensory experience of these formulations. However, current trends in cosmetic science aim to develop multifunctional products, where compounds traditionally used for texture or fragrance also possess biological activities that contribute to the product's efficacy. In this context, this study focuses on synthesizing derivatives of phytol—a compound already presents in cosmetic formulations—to enhance its anti-aging properties. The derivatives were synthesized through esterification with substituted benzoic and cinnamic acids, known for their antioxidant and enzyme inhibition properties. Reaction yields ranged from 91.0% to 5.2%, depending on the substituents in acid derivatives. The structures of the synthesized compounds were confirmed through NMR and MS techniques. Both the natural and newly synthesized derivatives were evaluated for their cosmeceutical potential using antioxidant assays and inhibition assays for tyrosinase, elastase, collagenase, and hyaluronidase. This work presents the first report of the synthesis and cosmetic evaluation of several of these derivatives. Comparing with phytol (1), which presented an IC50 of 77.47 µM, four of the derivatives presented improved tyrosinase inhibitory activity, with phytyl 4-methoxybenzoate being the most active (IC50 = 27.9 µM), followed by phytyl benzoate with an IC50 of 34.73 µM. Substitutions at other positions on the aromatic ring were less effective. Molecular docking studies confirmed that the modifications potentiated a stronger interaction between the synthesized compounds and tyrosinase. [ABSTRACT FROM AUTHOR]

Nucleosidic diarylethenes (DAEs) have evolved from an emerging class of photochromes into a well‐established option for integrating photochromic functionalities into biological systems. However, a comprehensive understanding of how chemical structure influences their photochromic properties remains essential. While structural features, such as an inverse connection between the aryl residues and the ethene bridge, are well‐documented for classical DAEs, their application to nucleosidic DAEs has been underexplored. In this study, we address this gap by developing three distinct types of inverse nucleosidic DAEs–semi‐inverse thiophenes, semi‐inverse uridines and inverse uridines. We successfully synthesized these compounds and conducted comprehensive analyses of their photostationary states, thermal stability, reversibility, and reaction quantum yields. Additionally, we conducted an in‐depth comparison of their photochromic properties with those of their normal‐type counterparts. Among the synthesized compounds, seven semi‐inverse thiophenes exhibited the most promising characteristics. Notably, these compounds demonstrated excellent fatigue resistance, with up to 96 % retention of photochromic activity over 40 switching cycles, surpassing the performance of all comparable nucleosidic DAEs reported to date. These findings hold significant promise for future applications in various fields. [ABSTRACT FROM AUTHOR]

Herein, we synthesized guanidine functionalized graphene oxide nanocomposites referred to GO‐GN NCs using hummer's method. GO‐GN NCs was characterized using Fourier‐Transform Infrared Spectroscopy, Powder X‐ray Diffraction, Thermogravimetric Analysis, Raman Spectroscopy, Field Emission Scanning Electron Microscopy, Transmission Electron Microscopy, Brunauer‐Emmett‐Teller (BET) surface area analysis to confirm successful formation of GO‐GN NCs catalysts. The catalytic performance for GO‐GN NCs was evaluated for Knoevenagel and Aldol condensation reaction in aqueous medium at ambient condition and result shows that it could be used as a highly efficient, stable, and durable catalyst. In addition, it has another feature such as easy workup procedure, large substrate tolerance, high reaction yield, good recyclability, and environmental friendliness. [ABSTRACT FROM AUTHOR]

Synthesis of novel benzothiazoles via intramolecular CS bond formation reactions is increasingly being explored since they have been found in a wide range of natural products and pharmaceutical agents. Sharma et al. reported the ruthenium‐catalyzed preparation of novel benzothiazole derivatives from N‐arylthiourea precursors, with a range of reaction yields and selectivity being observed. We have employed a density functional theory‐based computational model to investigate the reaction mechanism leading to the benzothiazole product and help uncover the origin of the differing experimental yields and substrate specificities. We proposed a modified mechanistic scheme where the rate‐determining step to be the synchronized breaking of the peroxide bond of the oxidizing agent with the concomitant proton‐coupled electron transfer from the haloarene urea and a Ru‐bound water molecule, not electrophilic RuC bond activation. Evidence for this being the rate‐determining step is (a) the barrier is consistent with a lack of kinetic isotope effects associated with the ortho‐H atom and (b) the computed rate‐determining barriers for 10 N‐arylthiourea substrates show good correlation with the observed yield. [ABSTRACT FROM AUTHOR]

This study investigates the palladium-catalyzed one-pot synthesis of functionalized furans from 1,3-Dicarbonyl compounds and alkenyl bromides, focusing on various catalysts and reaction parameters. Different catalysts, including PdCl₂(CH₃CN)₂, Pd(OAc)₂, and Pd(acac)2 as well as solvents, bases, and oxidants, were systematically evaluated. PdCl₂(CH₃CN)₂ emerged as the most effective catalyst, achieving a remarkable yield of 94%. Optimal reaction conditions were identified as PdCl₂(CH₃CN)₂ in dioxane at 80 °C with K₂CO₃ as the base and CuCl₂ as the oxidant. This study also explored various 1,3-diketones including Cyclohexane-1,3-dione, 5,5-Dimethylcyclohexane-1,3-dione, 2H-Pyran-3,5(4H,6H)-dione, Cyclopentane-1,3-dione, Pentane-2,4-dione, Ethyl 3-oxobutanoate, 1,3-Diphenylpropane-1,3-dione, 1,3-Dip-tolylpropane-1,3-dione, 1,3-Bis(4-chlorophenyl)propane-1,3-dione, and 1,3-Bis(4-bromo- phenyl)propane-1,3-dione, alongside different alkenyl bromides such as allyl bromide, (E)-1-Bromo-3,4-dimethylpent-2-ene, 1-Bromo-3-methylbut-2-ene, 3-Bromocyclohex-1-ene, and (E)-1-Bromohex-2-ene. These variations demonstrated the method's versatility and the significant impact of substituents on reactivity and reaction yield. These findings highlight the importance of optimizing reaction conditions to maximize efficiency and provide insights into improving catalytic processes for enhanced product yields. [ABSTRACT FROM AUTHOR]

In this paper, isatin-hydrazone was synthesized using SBA-Pr-N-Is-But-SO3H as nanocatalyst via the two-component reaction of isatin with hydrazine hydrate in an expeditious reaction with high yield of production. The sensing properties were evaluated in EtOH: H2O (1:9) for the different cation (K+, Ca2+, Na+, Cu2+, Zn2+, Cr3+, Mn2+, Co2+, Al3+, Pb2+, Ag+, Cd2+, Ni2+, Hg2+, and Mg2+). The obtained results revealed that these compounds could be applied as chemosensor for the sensitive detection of Hg2+ and Ag+ ions using UV–Vis spectroscopy and fluorescence spectroscopy, respectively. The detection limit was calculated to be 1.17 × 10–6 M for Hg2+ ions and 1.4 × 10–6 M for Ag+ ions. Also, isatin-hydrazone was treated with 4-flurobenzaldehyde to obtain 4-fluorobenzaldehyde-N-(2-oxo-1,2-dihydro-3H-indole-3-indole-3-ylidene)hydrazone which could sensitively select Hg2+ ions among different ions using fluorescence spectroscopy. The detection limit of the colorimetric sensor to detect the Hg2+ ions is 3.6 × 10–6 M. At the end of the reaction, the nanocatalyst was recovered and reused. [ABSTRACT FROM AUTHOR]

This study explores the potential mechanisms (Paths 1 and 2) involved in the regioselective dipolar cycloaddition of thioamides, selenoamides, and amides with propargyl alcohol using density functional theory (DFT). Our calculations reveal that the initial step involves the formation of a cation with catalyst. Subsequently, isomerization occurs between cations I and II via 1,3‐hydride transfer in the second step. We analyzed the global reactivity index and frontier molecular orbital (FMO) theory to gain insights into the mechanism. In the third step, chalcoamides attack cations I and II, forming an intermediate. The formation of a five‐member ring intermediate constitutes the fourth step, followed by hydrogen transfer to produce stable five‐member heterazole compounds in the final step. We demonstrated the influence of substituents in the electrophile by employing various electron‐withdrawing and donating groups. Additionally, we examined the effect of the dielectric medium on the reaction barrier using polarizable continuum model. Thus, this study provides valuable insights for the rational design of more efficient 1,3‐dipolar cycloaddition reactions yielding regioselective products. [ABSTRACT FROM AUTHOR]

The enhanced and direct immobilization of the enzyme horseradish peroxidase on poly(methyl methacrylate) (PMMA) microchannel surfaces to create a miniaturized enzymatic reactor for the biocatalytic oxidation of phenols is demonstrated. Enzyme immobilization occurs by physical adsorption after oxygen plasma treatment, which micro-nanotextures the PMMA surfaces. A five-fold enhancement in immobilized enzyme activity was observed, attributed to the increased surface area and, therefore, to a higher quantity of immobilized enzymes compared to an untreated PMMA surface. The enzymatic reaction yield reached 75% using a flow rate of 2.0 μL/min for the reaction mixture. Additionally, the developed microreactor was reused more than 16 times without affecting the enzymatic conversion yield. These results demonstrate the potential of microchannels with plasma micro/nanotextured surfaces for the rapid and facile fabrication of microfluidic enzymatic microreactors with enhanced catalytic activity and stability. [ABSTRACT FROM AUTHOR]

Chlormequat chloride (CCC), as a commonly used plant growth regulator in the production of rhizomatous medicinal herbs, can effectively control the bolting phenomenon in Angelica sinensis, significantly increasing the yield of underground rhizomes (medicinal part). However, its specific effects on the intrinsic quality of Angelica sinensis, especially medicinal components, require further investigation. The objective of this study is to conduct a thorough examination of CCC residue and its influence on the yield and medicinal components of Angelica sinensis. By spraying different concentrations of CCC on Angelica sinensis, we systematically monitored the final yield of Angelica sinensis Radix (ASR) in each treatment group and the residual concentration of CCC in ASR. Using UPLC-QTOF-MS technology, we conducted an in-depth analysis of the metabolic profile of ASR. Subsequently, UFLC-MS/MS was employed to accurately quantify the changes in the content of nine key active components in ASR. The results of this study indicate that the application of CCC significantly improves the yield of ASR, with the best effect observed at 0.1 g/L, resulting in a yield increase of 24.8%. Meanwhile, the residual amount of CCC in ASR is positively correlated with the application concentration, with the residual levels as high as 7.12 mg/kg in the high-concentration treatment group. Metabolomic analysis preliminarily identified 21 chemical components in ASR, including four organic acids and 13 phthalides. It is worth noting that the quantitative analysis results indicate significant changes in active components such as butylphthalide, Z-ligustilide, and ferulic acid after the application of CCC. Specifically, high-concentration CCC significantly increased the content of butylphthalide and levistolide A, while low-concentration CCC significantly promoted the accumulation of coniferyl ferulate and senkyunolide A, accompanied by a significant decrease in Z-ligustilide and ferulic acidy. In conclusion, while CCC use can increase yield, the associated increase in residues and imbalanced composition ratios may threaten the quality and safety of ASR. Therefore, it is crucial to control the amount of CCC used rationally to balance yield enhancement and quality assurance. [ABSTRACT FROM AUTHOR]

This study conducts a comparative analysis of cystamine (RSSR), a disulfide, and cysteamine (RSH), its thiol monomer, to evaluate their efficacy as radioprotectors and antioxidants under high linear energy transfer (LET) and high-dose-rate irradiation conditions. It examines their interactions with reactive primary species produced during the radiolysis of the aqueous ferrous sulfate (Fricke) dosimeter, offering insights into the mechanisms of radioprotection and highlighting their potential to enhance the therapeutic index of radiation therapy, particularly in advanced techniques like FLASH radiotherapy. Using Monte Carlo multi-track chemical modeling to simulate the radiolytic oxidation of ferrous to ferric ions in Fricke-cystamine and Fricke-cysteamine solutions, this study assesses the radioprotective and antioxidant properties of these compounds across a variety of irradiation conditions. Concentrations were varied in both aerated (oxygen-rich) and deaerated (hypoxic) environments, simulating conditions akin to healthy tissue and tumors. Both cystamine and cysteamine demonstrate radioprotective and strong antioxidant properties. However, their effectiveness varies significantly depending on the concentration employed, the conditions of irradiation, and whether or not environmental oxygen is present. Specifically, excluding potential in vivo toxicity, cysteamine substantially reduces the adverse effects of ionizing radiation under aerated, low-LET conditions at concentrations above ~1 mM. However, its efficacy is minimal in hypoxic environments, irrespective of the concentration used. Conversely, cystamine consistently offers robust protective effects in both oxygen-rich and oxygen-poor conditions. The distinct protective capacities of cysteamine and cystamine underscore cysteamine's enhanced potential in radiotherapeutic settings aimed at safeguarding healthy tissues from radiation-induced damage while effectively targeting tumor tissues. This differential effectiveness emphasizes the need for personalized radioprotective strategies, tailored to the specific environmental conditions of the tissue involved. Implementing such approaches is crucial for optimizing therapeutic outcomes and minimizing collateral damage in cancer treatment. [ABSTRACT FROM AUTHOR]

In this work, a Pd(II)-C,N-cyclometalated complex was grafted to polysiloxanes via azide–alkyne cycloaddition. The obtained polymer–metal complex (Pd-PDMS) acts as a catalyst in the Suzuki–Miyaura reaction. Pd-PDMS was drop-casted onto a carbon fiber support, and the resulting membrane demonstrated catalytic activity in the cross-coupling reaction without yield loss after several catalytic cycles. The catalytic membrane allows for easy catalyst recycling and provides ultra-low palladium levels in Suzuki–Miyaura reaction products. [ABSTRACT FROM AUTHOR]

This paper details the cross-section measurements of 38 fission-like events in 19F + 181Ta system at energy 115 MeV, originating from complete and/or incomplete fusion-fission processes. The recoil-catcher off-beam activation technique followed by γ-ray spectroscopy has been used to measure production cross sections of fission-like events. The measured cross-section data of fission-like events align well with Gaussian distributions indicating their production via de-excitation of equilibrated compound nucleus formed. Additionally, the study explores mass and isotopic yield distributions of fission fragments, with the presently measured isotopic yield variance which is found to be consistent with literature values for other fissioning systems. [ABSTRACT FROM AUTHOR]

Crowding induces behavioural and lasting morphological and chromatic changes in insects. This study examined how larval rearing density of Propylea dissecta (Mulsant, 1850) affected food choice and development duration, hypothesising that larvae under stress will opt for lower quality food as larval density increases. Larvae were reared at various densities under three crowding treatments: direct physical, indirect physical, and chemical tracks. In each treatment, larvae experienced crowding at densities of 0, 2, 4, 6, 8, 10, and 12 individuals per arena. Fourth stage larvae were provided with food choice of aphids, heterospecific eggs, and conspecific eggs. Significant effect of crowding on total development duration, first consumption time, and first food consumption was observed. Decrease in development duration at densities of 4 and 6 and increase in development duration at low and high densities were observed in direct physical crowding. Indirect physical and chemical crowding yield the shortest development duration at densities of 8, 10, and 12, when compared to low and moderate crowding. First encounter time increased with increasing chemical tracks concentration, while first consumption time decreases with crowding across all groups. First consumed food was also significantly influenced by crowding, suggesting a negative impact on larval food choice. Our results indicate that crowding among larvae leads to a longer development duration and show less selectivity in their food choices. [ABSTRACT FROM AUTHOR]

Asymmetric synthesis of chiral chemicals in high enantiomeric excess (ee) is pivotal to the pharmaceutical industry, but classic chemistry usually requires multi‐step reactions, harsh conditions, and expensive chiral ligands, and sometimes suffers from unsatisfactory enantioselectivity. Enzymatic catalysis is a much greener and more enantioselective alternative, and cascade biotransformations with multi‐step reactions can be performed in one pot to avoid costly intermediate isolation and minimise waste generation. One of the most attractive applications of enzymatic cascade transformations is to convert easily available simple racemic substrates into valuable functionalised chiral chemicals in high yields and ee. Here, we review the three general strategies to build up such cascade biotransformations, including enantioconvergent reaction, dynamic kinetic resolution, and destruction‐and‐reinstallation of chirality. Examples of cascade transformations using racemic substrates such as racemic epoxides, alcohols, hydroxy acids, etc. to produce the chiral amino alcohols, hydroxy acids, amines, and amino acids are given. The product concentration, ee, and yield, scalability, and substrate scope of these enzymatic cascades are critically reviewed. To further improve the efficiency and practical applicability of the cascades, enzyme engineering to enhance catalytic activities of the key enzymes using the latest microfluidics‐based ultrahigh‐throughput screening and artificial intelligence‐guided directed evolution could be a useful approach. [ABSTRACT FROM AUTHOR]

A sustainable and scalable protocol for synthesizing variously functionalized sulfonamides, from amines and sulfonyl chlorides, has been developed using environmentally responsible and reusable choline chloride (ChCl)‐based deep eutectic solvents (DESs). In ChCl/glycerol (1 : 2 mol mol−1) and ChCl/urea (1 : 2 mol mol−1), these reactions yield up to 97 % under aerobic conditions at ambient temperature within 2–12 h. The practicality of the method is exemplified by the sustainable synthesis of an FFA4 agonist and a key building block en route to anti‐Alzheimer drug BMS‐299897. A subtle interplay of electronic effects and the solubility characteristics of the starting materials in the aforementioned DESs seem to be responsible for driving the reaction successfully over the hydrolysis of sulfonyl chlorides. The procedure's eco‐friendliness is validated by quantitative metrics like the E‐factor and the EcoScale, with products isolated by extraction or filtration after decantation. [ABSTRACT FROM AUTHOR]

4-Arylideneisoxazol-5(4H)-ones were obtained via a simple and efficient one-pot, three-component cyclocondensation of diverse aldehydes with hydroxylamine hydrochloride and β-keto esters in water. This one-pot heterocyclization has been performed in the presence of catalytic amounts of silicon dioxide nanoparticles (SiO2 NPs) at room temperature. This approach is economical for the synthesis of potentially bioactive 4-arylideneisoxazol-5(4H)-one derivatives. The products were formed in 86–94% isolated reaction yields using 5 mol% nanocatalyst. The heterocyclization reactions were completed at room temperature under aqueous conditions. The significant features of the present procedure are uncomplicated product isolation, purification without chromatographic methods, great biocompatibility of SiO2 NPs, straightforward reaction conditions, easy workup, environmentally friendly, readily available starting materials, reusability of the catalyst, as well as inexpensive and green reaction medium. [ABSTRACT FROM AUTHOR]