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The interactions between π-systems in dimers of aromatic molecules lead to particularly stable conformations within the relative orientations of the monomers. Extensive research has been conducted on the properties of these complexes in the neutral state. However, in recent decades, there has been a significant surge in applications harnessing these structures for electrical purposes. Therefore, this study places particular emphasis on a deeper understanding of the redox properties of these compounds and how to modify them. To achieve this, we have focused on modeling the effect of a wide range of functional groups on the redox properties of benzene derivatives, observing a correlation between these properties and the change in the molecular dipole moment. Then, we investigated the effect of π-stacking interactions on these properties in dimers formed by either identical or different monomers. In both cases, there is an enhancement of the reducing character of the systems due to these interactions. Upon oxidation, the charge is distributed proportionally to the redox potential of each monomer. Therefore, if there is heterogeneity in these potentials, the properties of the complete cationic system will be influenced by the monomer with a greater tendency to undergo oxidation. The considered models serve as an excellent example for studying the behavior of nucleobases in DNA or aromatic amino acids, among others. [ABSTRACT FROM AUTHOR]

Photobromination of toluene derivatives using blue LED (454 nm) or UV LEDs (365, 385, 395 nm) with aqueous HBr and NaOCl·5H2O in trifluoromethyl benzene afforded the corresponding benzoic acids derivatives. The intermediates were (dibromomethyl)benzene derivatives, isolated in a nitrogen atmosphere. The dibromomethyl benzene derivatives afforded the corresponding aldehydes. After the reaction with HBr, the aqueous layer could be recovered and reused. [ABSTRACT FROM AUTHOR]

The aim of the research is to determine changes in the composition of selected gasoline compounds in cotton carpet samples due to different weathering times. EVO 95 gasoline was used as a fire accelerant and a cotton carpet was used as a matrix. The samples were exposed to various weathering durations (0–360 min) in laboratory conditions. We investigated samples that were unburnt (only weathered) and samples that were burned and subsequently subjected to further weathering. Residual gasoline compounds in carpet samples were determined by gas phase extraction (headspace – HS) coupled with gas chromatography (GC) and mass spectrometry (MS). We focused on the comparison of selected gasoline compounds; toluene, ethylbenzene, p-xylene, 1,2,3-trimethylbenzene (TMB), 1,3,5-trimethylbenzene and naphthalene. The biggest changes were determined in the reduction of the intensity of most volatile compounds (alkylalkanes), where toluene decreased by 11.92%. A similar but not so pronounced trend, occurred in the burned samples, where toluene decreased by 7.40%. Minor changes occurred in alkyl derivatives of benzene, where some of the total 15 gasoline markers also occur, e.g. (1,2,3-trimethylbenzene, 1,3,5-trimethylbenzene). On the contrary, naphthalene as a heavier compound showed an increase in intensity about 0.42%. For burnt samples, the increase was 1.31%. The results show that largest changes can be observed after four or five hours of weathering, which implies the need for rapid sampling and subsequent timely analysis. [ABSTRACT FROM AUTHOR]

This document provides information about the synthesis and characterization of various compounds, including indazoles and pyrazolopyridines. The compounds were synthesized using specific reactions and purification techniques, and their structures were confirmed using various spectroscopic techniques. The document includes data such as chemical shifts, yields, melting points, and spectroscopic data for each compound. The authors acknowledge the support of the Central Laboratory of Pharmacy at Ankara University and declare no conflicts of interest. [Extracted from the article]

The spirocyclic framework is found in many natural products, some of which are biologically active. However, It remains a challenge to develop environmentally friendly and atom‐economic synthetic methods. Herein, we report an intramolecular dearomatization reaction of benzene derivatives enabled by electrochemistry‐mediated two successive single‐electron‐transfer (SET) processes, providing an alternative method for the rapid construction of spirocyclic skeletons without using sacrificial reagents. A series of cyclohexadiene products were obtained in 25–81% yields. Furthermore, a proposed mechanism involving a sequential electron transfer event was supported by cyclic voltammetry experiments. This strategy features transition‐metal‐free conditions and easy handling, which will greatly enhance its practical utility. [ABSTRACT FROM AUTHOR]

Rajasthan, experiencing rapid industrialization and urbanization, faces critical air quality challenges, particularly concerning toxic volatile organic compounds (VOCs) such as BTEX (Benzene, Toluene, Ethylbenzene, Xylene). This study presents a long-term analysis of BTEX concentrations across various cities in Rajasthan, India, using data from the Central Pollution Control Board (CPCB) from 2017 to 2022. The findings revealed that the average ∑BTEX concentrations increased from 4.15 µg/m3 in 2017 to 12.29 µg/m3 in 2022, with a temporary decline in 2020. The Hazard Quotient (HQ) values for BTEX exposure ranged from 0.052 to 0.15 for males, 0.056 to 0.17 for females, and 0.09 to 0.29 for children over the study period, indicating higher health risks for children. Similarly, the Lifetime Cancer Risk (LCR) values varied from 6.04 × 10⁻⁶ to 1.92 × 10⁻5 for males, 1.09 × 10⁻⁶ to 2.24 × 10⁻5 for females, and 1.17 × 10⁻5 to 3.73 × 10⁻5 for children. The results demonstrate that children are at a greater cancer risk from BTEX exposure compared to adults. This study emphasizes the urgent need for effective air pollution control measures and continuous monitoring to protect public health, particularly vulnerable populations like children. [ABSTRACT FROM AUTHOR]

To investigate the effect of gamma irradiation on the volatile compounds of edible oils. Three types of oilseeds, including peanut, sesame, and flaxseed, were subjected to 8 kGy gamma irradiation, followed by cold pressing to extract their oils. The volatile compounds of the oils were isolated by simultaneous distillation extraction and analyzed by gas chromatography‐mass spectrometry. A total of 91 volatile compounds were identified, which can be grouped into eight categories: hydrocarbons, aldehydes, ketones, alcohols, acids, esters, furans, and benzene derivatives. Irradiation treatment resulted in a significant increase in the levels of hydrocarbons, aldehydes, and ketones in all oil samples (p < 0.05), with the greatest increase observed in hydrocarbons (4–14 times). In contrast, changes in alcohols, acids, esters, furans, and benzene derivatives were related to oilseed type. The increased hydrocarbons mainly originated from the degradation of palmitic, stearic, oleic, and linoleic acids. The irradiation resistance of the three oilseeds varied considerably, in the order: flaxseed > sesame > peanut. Based on the odor activity value, 11 key aroma compounds were selected, and (E)‐2‐decenal (tallow, oily, and orange), 1‐octanol (soapy and oily), and 1‐nonanol (floral and soapy) were only detected in the irradiated samples. Principal component analysis revealed that the oil samples of the three oilseeds could be well classified based on their key aroma compounds, and that the irradiation treatment had no remarkable effect on their intrinsic aroma. [ABSTRACT FROM AUTHOR]

Microwave (MW)‐assisted catalytic pyrolysis represents a promising method for transforming petroleum‐based plastic waste into valuable chemicals, offering a pathway towards more sustainable circular economy. In this study, catalytic pyrolysis of low‐density polyethylene (LDPE) was conducted under MW irradiation. The influence of various catalyst types (HZSM‐5, Ga/ZSM‐5, Ga/Ni/ZSM‐5, Ga/Co/ZSM‐5, and Ga/Cu/ZSM‐5) on product yield and distribution was examined. The results revealed that the Ga/ZSM‐5 catalyst yielded the maximum liquid oil, approximately 41%. Ga/Ni/ZSM‐5 performed excellently in the production of long‐chain olefins, constituting about 27% of the liquid fraction. However, Ga/Co/ZSM‐5 led to the production of heavy pyrolysis oil containing nearly 25% long‐chain paraffins, rendering it unsuitable for producing high‐value chemicals. Conversely, the Ga/Cu/ZSM‐5 catalyst yielded an aromatic‐rich pyrolysis oil, with benzene derivatives constituting approximately 90% of the liquid oil fraction, thus proving to be a suitable catalyst for the intended application. The liquid product distribution was compared with a petroleum assay by SimDist, and this suggested that utilizing the HZSM‐5 catalyst could yield an 86.4% naphtha fraction. The study also revealed that the Ga/Cu/ZSM‐5 catalyst generated the largest amounts of hydrogen and syngas, as determined by a MicroGC analysis of the gas products. This catalyst also exhibited the maximum coke deposition (1.35%) postreaction, which was attributed to its high aromatic hydrocarbon content in the pyrolysis oil and maximal hydrogen release. A comparison of fresh and spent catalyst properties was conducted to gain insights into catalyst activity and to correlate the effects of metal doping on product distribution. These findings underscore the potential of MW‐assisted catalytic pyrolysis, particularly with the Ga/Cu/ZSM‐5 catalyst, for the efficient conversion of plastic waste into valuable chemicals, thereby contributing to sustainable resource utilization and environmental conservation. [ABSTRACT FROM AUTHOR]

The selective borylation of specific C−H bonds in organic synthesis remains a formidable challenge. In this study, we present a novel spirobipyridine ligand that features a binaphthyl backbone. This ligand facilitates the iridium‐catalyzed selective C−H borylation of benzene derivatives. The ligand is designed with "side‐arm‐wall" substituents that allow vicinal di‐ or multi‐substituted benzene derivatives to approach metal center and effectively block other reactive sites by non‐covalent interactions with substrates. The effectiveness of this strategy is demonstrated by the successful selective distal C−H activation of various alkaloids and its broad compatibility with functional groups. [ABSTRACT FROM AUTHOR]

Cardiovascular disease (CVD) is a leading cause of global mortality, with dyslipidemia being a significant modifiable risk factor. Dyslipidemia refers to all abnormalities in blood lipid levels. It plays a fundamental role in the development and progression of atherosclerosis. The reduction of low‐density lipoprotein (LDL) cholesterol has been shown to decrease cardiovascular risk. Cholesteryl ester transfer protein (CETP) plays a role in LDL metabolism, and its inhibition results in lower LDL levels. This study synthesizes and evaluates novel benzene sulfonamide derivatives as CETP inhibitors. Twenty compounds were synthesized and tested for their inhibitory activity using an in vitro bioassay. The results revealed that para‐methylated derivatives exhibited higher inhibitory activity compared to meta‐methylated derivatives, where compound 6n has an IC50 of 24.4 µM. Furthermore, electron withdrawing groups such as chlorine and nitro substitutions on the sulfanamido‐phenyl rings demonstrated superior inhibitory effects compared to electron donating groups. Positional isomerism of the substitutions also influenced inhibitory activity, with para substitutions being more effective. Nitro‐substituted compounds showed greater inhibition than chlorine‐substituted compounds, where compound 6t has an IC50 of 18.3 µM. Overall, this study provides valuable insights into the SAR of CETP inhibitors and identifies promising compounds for further investigation as potential therapeutics for CVD. [ABSTRACT FROM AUTHOR]

Background: Triple-negative breast cancer (TNBC) is a subtype of breast cancer characterized by poor prognosis due to the absence of effective targeted therapies. Emerging evidence indicates that the gut microbiota and its metabolites play a key role in the occurrence and development of TNBC. This study aimed to explore the metabolic changes and potential mechanisms associated with TNBC. Objectives: This study aimed to explore the potential relationship between targeted metabolites and the gut microbiota in TNBC. Design: We recruited 8 participants, including 4 with TNBC and 4 with benign fibroadenomas as controls. Methods: The gut microbiota was analyzed using metagenomics on fecal samples. Liquid chromatography–mass spectrometry (LC-MS) was employed to identify differential metabolites in serum and fecal samples. The correlation between the gut microbiota and metabolites was analyzed using Spearman's correlation analysis. Results: Analysis of altered serum metabolites in the TNBC group revealed changes, particularly in carboxylic acids and derivatives, benzene, and substituted derivatives. Kyoto Encyclopedia of Genes and Genomes (KEGG) metabolic pathway analysis revealed significant enrichment in 18 pathways. Regarding fecal metabolites, differences between the 2 groups also included carboxylic acids and derivatives, benzene, and substituted derivatives, with 28 metabolic pathways enriched based on KEGG pathway analysis. Metagenomics analysis showed differences in the relative abundance of Anaerococcus, Fischerella, and Schizosaccharomyces at the genus level, which have been previously associated with breast cancer. Furthermore, 4 serum metabolites—L-glutamine, citrate, creatinine, and creatine—along with 9 fecal metabolites, were associated with the aforementioned microbiota. Conclusion: Our findings highlight distinct metabolite profiles in the serum and feces of patients with TNBC. The identification of gut microbiota and their associated metabolites provides new insights into the pathophysiological mechanisms underlying TNBC. [ABSTRACT FROM AUTHOR]

Depilation through laser hair removal has gained popularity due to its long-lasting effects, which can last for several months and, in some cases, be considered permanent. This method also improves quality of life. However, common complications include blistering, pigmentary changes, and scabbing. Folliculitis is rare, with most cases being mild and transient. We hereby report on a 33-year-old healthy Thai male who rapidly developed severe folliculitis one day after undergoing diode laser treatment, which combined three wavelengths (755 nm, 810 nm, and 1,064 nm) into a single pulse. The condition improved significantly following a short course of prednisolone and topical benzoyl peroxide. At the 4-week follow-up, the lesions had nearly resolved, with only a few erythematous papules and hyperpigmented follicular macules remaining and no scarring. Further studies are needed to clarify the mechanism of folliculitis after hair removal laser treatment, enabling more effective prevention and management for patients. [ABSTRACT FROM AUTHOR]

This study involves the synthesis of asterism compounds (D1-D6) through the reaction of 1 mole of benzene 1,3,5-triol with 3 moles of prepared pentacyclic ring ester derivatives, dissolved in absolute ethanol. The validity of the compound structures was confirmed using physical and spectroscopic methods such as infrared spectroscopy, and proton nuclear magnetic resonance spectroscopy. Additionally, melting points and purity were determined, and reaction progress was monitored by Thin-Layer Chromatography (TLC). The liquid crystal phases of certain prepared compounds were examined using a polarizing optical microscope (POM). [ABSTRACT FROM AUTHOR]

Aim: Periodontitis is one of the most common oral diseases and a major cause of tooth loss in adults. Environmental pollution is closely associated with the prevalence of periodontitis. However, few studies have focused on the association between volatile organic compounds (VOCs) and periodontitis. This cross‐sectional study aims to examine whether exposure to VOCs is associated with periodontitis, based on data from the National Health and Nutrition Examination Survey (NHANES, 2011–2014). Materials and Methods: We analysed data on blood VOC levels, periodontitis and related covariates from 2772 participants of the NHANES. The association between the blood VOCs and periodontitis was analysed using weighted logistic regression analysis, the restricted cubic spline (RCS) model and the weighted quantile sum (WQS) regression model. Interaction tests and mediation analysis were also conducted. Results: After adjusting for covariates, for each natural constant‐fold increase in 1,4‐dichlorobenzene, the odds of having periodontitis increased by 16% (odds ratio = 1.16; 95% confidence interval: 1.08–1.24, p <.001). WQS regression model indicated that 1,4‐dichlorobenzene contributed the most to the association between VOC co‐exposure and periodontitis. Mediation analysis further revealed that total bilirubin levels mediated the association between 1,4‐dichlorobenzene and the prevalence of periodontitis, accounting for 4.32%. In addition, the positive association between o‐xylene and periodontitis was more pronounced in the <65‐year‐old group. Conclusions: This study has provided relatively little evidence to demonstrate a specific link between VOCs and periodontitis. Nonetheless, exposure to VOCs remains a non‐negligible public health concern, and further research is required to investigate the association and potential mechanisms of action between VOCs and periodontitis. [ABSTRACT FROM AUTHOR]

Simple Summary: High-risk neuroblastoma, especially when it recurs, is challenging to treat. Since immunotherapy and target therapy have been incorporated in the treatment of these patients, tissue sample collection has a key impact on their management and prognosis. However, tissue sampling is often difficult to obtain in this population. This study investigates the use 123I-MIBG radioguided surgery, which helps surgeons access hard-to-reach areas of neuroblastoma. By using a gamma probe to detect and remove the tumor tissue, this method aims to improve tissue sampling and, ultimately, patient outcomes. The findings show that this technique was successful in all cases, allowing for complete tumor removal and enabling important molecular studies to be conducted. This approach could significantly impact how we treat and study high-risk neuroblastoma. Introduction: High-risk neuroblastoma, particularly in the relapse/refractory (R/R) setting, poses unique challenges to obtaining the representative-quality tissue that is mostly required for molecular analysis. This study explores the use of 123I-MIBG radioguided surgery to access complex locations of MIBG-positive neuroblastoma as a tool to overcome the difficulties associated with repeated surgeries in these patients. Methods: This study is a retrospective review of all patients with R/R neuroblastoma and MIBG-uptaking lesions who underwent radioguided surgery between February 2020 and 2023 at SJD Barcelona Children's Hospital. The Europrobe 3.2 gamma probe was used to identify neuroblastoma tissue in the operating room. Results: Ten patients were identified. Radioguided surgery was useful in all patients. One patient with previous multiple operations developed an entero-cutaneous fistula with posterior full recovery. Mean surgical time was 111.7 min. The gamma probe identified 100% of neuroblastoma lesions which were all completely removed (123I-MIBG-SPECT/CT negative post-surgery). Pathology and molecular studies could be successfully performed in all samples. Conclusions: 123I-MIBG radioguided surgery proved effective in obtaining viable tissue from difficult-to-access sites in high-risk relapsed neuroblastoma. [ABSTRACT FROM AUTHOR]

A series of the new 1,2,3-triazole-acetophenone hybrid system are synthesized from the click reaction between 1-(2-(prop-2-yn-1-yloxy)phenyl)ethan-1-one 1 and different azido benzene derivatives 2-7. All compounds are characterized by 1H NMR, 13C NMR, mass spectra, and elemental analyses. Field Emission Scanning Electron Microscope (FESEM) detected highly ordered aggregations, and the morphology of the compounds was determined, directed by van der Waals (vdW) forces and π-π stacking interactions. The Gaussian 09 and Gaussian view 6.0 softwares are used for all Density Functional Theory (DFT) calculations at the B3LYP. Band gap, molecular softness, electronegativity, and electrophilicity measurements show that molecule 9 is a soft molecule with higher polarizability, lower kinetic stability, and more chemical reactivity than the other molecules, which tend to be the most stable and least reactive. The molecules can be divided into two categories based on their chemical potential values: Although compound 9 looks to have more activity, compounds 8, 10, 11, 12, and 13 often have the best stability and least reactivity. According to the MEPs, the nitrogen and oxygen atoms are the electronegative potential sites in all compounds, while the hydrogen atoms in the alkyl and aromatic cyclic groups are the electropositive potential sites. [ABSTRACT FROM AUTHOR]

Introduction: Endocrine disrupting chemicals (EDCs) as benzene phenolic derivatives being hydrophobic partition to organic matter in sludge/soil sediments and show slow degradation rate owing to poor bioavailability to microbes. Methods: In the present study, the potential of a versatile white rot fungal isolate S5 identified as Hypocrea lixii was monitored to degrade bisphenol A (BPA)/triclosan (TCS) under shake flask conditions with concomitant production of lipopeptide biosurfactant (BS) and plant growth promotion. Results: Sufficient growth of WRF for 5 days before supplementation of 50 ppm EDC (BPA/TCS) in set B showed an increase in degradation rates by 23% and 29% with corresponding increase in secretion of lignin-modifying enzymes compared to set A wherein almost 84% and 97% inhibition in fungal growth was observed when BPA/TCS were added at time of fungal inoculation. Further in set B, EDC concentration stimulated expression of laccase and lignin peroxidase (Lip) with 24.44 U/L of laccase and 281.69 U/L of Lip in 100 ppm BPA and 344 U/L Lip in 50 ppm TCS supplemented medium compared to their respective controls (without EDC). Biodegradation was also found to be correlated with lowering of surface tension from 57.02 mN/m (uninoculated control) to 44.16 mN/m in case of BPA and 38.49 mN/m in TCS, indicative of biosurfactant (BS) production. FTIR, GC-MS, and LC-ESI/MSMS confirmed the presence of surfactin lipopeptide isoforms. The WRF also displayed positive plant growth promoting traits as production of ammonia, indole acetic acid, siderophores, Zn solubilization, and 1-1-aminocyclopropane-1-carboxylate (ACC) deaminase activity, reflecting its soil restoration ability. Discussion: The combined traits of biosurfactant production, EDC degradation and plant growth promotion displayed by WRF will help in emulsifying the hydrophobic pollutants favoring their fast degradation along with restoration of contaminated soil in natural conditions. [ABSTRACT FROM AUTHOR]

In this work we report the development of an electrochemical sensor based on a modified glassy carbon electrode (GCE) modified with reduced graphene oxide (rGO) for simultaneous determination of p-benzoquinone (BQ) and resorcinol (RS) in soil and water samples of gas stations, using the electrochemical techniques of cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and square wave voltammetry (SWV). The sensor modification was carried out by drop casting, a 10 µL aliquot of the rGO suspension was dropped onto the surface of the GCE. The sensor showed a linear response for both analytes through SWV from 20 µM up to 100 µM. Good results of sensitivity, limit of detection (LOD), and quantification (LOQ) were obtained for BQ (0.03 µA µM−1, 0.37 µM, and 1.23 µM) and RS (0.07 µA µM−1, 0.81 µM, and 2.71 µM), respectively. The method was tested in environmental samples (soil and water) through spike and recovery procedure (recovery > 99%), with precision (RSD) of 0.10% (BQ) and 0.36% (RS). [ABSTRACT FROM AUTHOR]

A single-step phenylation at the non-acidic C(sp3)–H bond attached to the heteroatom of ethers and N -Boc-amines has been achieved using photoexcited 4-benzoylpyridine as a hydrogen atom transfer (HAT) catalyst. The design of electron-deficient (trifluoromethylsulfonyl)benzene derivatives, as a phenyl precursor, was critical to realizing the present transformation. Moreover, the DFT calculations indicated that the present transformation proceeds via a concerted homolytic aromatic substitution rather than via a stepwise one involving the formation of a cyclohexadienyl radical intermediate. [ABSTRACT FROM AUTHOR]

The COVID-19 pandemic of 2020, marked by stringent lockdowns and reduced human activity, resulted in a significant decrease in air pollutant emissions. This study investigates the impact of these altered atmospheric conditions on human health by focusing on Volatile Organic Compounds (VOCs) such as benzene, toluene, and meta-xylene (BTX), comparing data from before, during, and after the pandemic lockdowns. The objectives were to assess changes in Total VOC (TVOC) concentrations and to evaluate the associated health risks, particularly Lifetime Cancer Risk (LCR) from benzene exposure. Analysis of the data revealed a notable reduction in TVOCs during the 2020 lockdown, with average concentrations of 12.15 ± 20.49 µg/m3 in 2019, 8.08 ± 5.50 µg/m3 in 2020, and 5.12 ± 7.56 µg/m3 in 2021. LCR values also fluctuated, with averages of 1.12 × 10−5, 1.23 × 10−5, and 6.91 × 10−6 or pre-pandemic, during-pandemic, and post-pandemic periods, respectively. The findings highlight the potential effectiveness of lockdowns in reducing air pollution and underscore the need for continued, targeted environmental policies to improve public health. [ABSTRACT FROM AUTHOR]

A novel route for C(sp3)-N bond formation via C(sp2)−H activation/reduction by metal-free which uses (E)- N ′-benzylideneacetohydrazide and (vinylsulfonyl)benzene to synthesize derivatives of (E)- N ′-benzylidene- N -(2-(phenylsulfonyl)ethyl)acetohydrazide has been reported. This methodology features good functional group tolerance and convenient operation. In addition, it uses inexpensive and insensitive chemical reagents as raw materials and provides an atom- and efficient method for the preparation of (E)- N ′-benzylidene- N -(2-(phenylsulfonyl)ethyl)acetohydrazides. [ABSTRACT FROM AUTHOR]

A series of methoxylated bis(pentafluorophenyl)boron‐β‐diketonates (dkB(C6F5)2) with intense emission has been synthesized and characterized by a variety of physicochemical methods. The photophysical properties of the synthesized compounds were thoroughly investigated by electronic absorption, steady‐state, and time‐resolved fluorescence spectroscopy in both solution and solid state. The studied compounds exhibit solvatochromic behavior attributed to the intramolecular charge transfer (ICT) nature of the first excited state. The formation of exciplexes between DBMB(C6F5)2 and benzene derivatives was also studied. Notably, the studied compounds display a complex luminescence profile in the solid state, featuring fluorescence, delayed fluorescence and phosphorescence emission. Furthermore, the hydrolytical stability of the complexes was assessed, demonstrating excellent resistance to hydrolysis. Estimated rate constants, determined at 60 °C, are significantly lower (90‐2000 times) than those observed for the well‐studied dibenzoylmethanatoboron difluoride (DBMBF2). The incorporation of pentafluorophenyl substituents at the boron atom enables the synthesis of highly fluorescent and hydrolytically stable boron chelate complexes, suitable for sensing and bioimaging applications in water‐containing environments. [ABSTRACT FROM AUTHOR]

By taking into account our previously described series of 1,3,5-tris[(4-(substituted-aminomethyl)phenyl)methyl]benzene compounds, we have now designed, prepared, and evaluated in vitro against Plasmodium falciparum a novel series of structural analogues of these molecules, i.e., the 1,3,5-tris[(4-(substituted-aminomethyl)phenoxy)methyl]benzene derivatives. The pharmacological data showed antimalarial activity with IC50 values in the sub and μM range. The in vitro cytotoxicity of these new nitrogen polyphenoxymethylbenzene compounds was also evaluated on human HepG2 cells. The 1,3,5-tris[(4-(substituted-aminomethyl)phenoxy)methyl]benzene derivative 1m was found as one of the most potent and promising antimalarial candidates with favorable cytotoxic to antiprotozoal properties in the P. falciparum strains W2 and 3D7. In conclusion, this 1,3,5-tris[(4-(pyridin-3-ylmethylaminomethyl)phenoxyl)methyl]benzene 1m (IC50 = 0.07 μM on W2, 0.06 μM on 3D7, and 62.11 μM on HepG2) was identified as the most promising antimalarial derivative with selectivity indexes (SI) of 887.29 on the W2 P. falciparum chloroquine-resistant strain, and of 1035.17 on the chloroquine-sensitive and mefloquine decreased sensitivity strain 3D7. It has been previously described that the telomeres of P. falciparum could represent potential targets for these types of polyaromatic compounds; therefore, the capacity of our novel derivatives to stabilize the parasitic telomeric G-quadruplexes was assessed using a FRET melting assay. However, with regard to the stabilization of the protozoal G-quadruplex, we observed that the best substituted derivatives 1, which exhibited some interesting stabilization profiles, were not the most active antimalarial compounds against the two Plasmodium strains. Thus, there were no correlations between their antimalarial activities and selectivities of their respective binding to G-quadruplexes. [ABSTRACT FROM AUTHOR]

A series of biotin-functionalized transition metal complexes was prepared by iClick reaction from the corresponding azido complexes with a novel alkyne-functionalized biotin derivative ([Au(triazolatoR,R′)(PPh3)], [Pt(dpb)(triazolatoR,R′)], [Pt(triazolatoR,R′)(terpy)]PF6, and [Ir(ppy)(triazolatoR,R′)(terpy)]PF6 with dpb = 1,3-di(2-pyridyl)benzene, ppy = 2-phenylpyridine, and terpy = 2,2′:6′,2′′-terpyridine and R = C6H5, R′ = biotin). The complexes were compared to reference compounds lacking the biotin moiety. The binding affinity toward avidin and streptavidin was evaluated with the HABA assay as well as isothermal titration calorimetry (ITC). All compounds exhibit the same binding stoichiometry of complex-to-avidin of 4:1, but the ITC results show that the octahedral Ir(III) compound exhibits a higher binding affinity than the square-planar Pt(II) complex. The antibacterial activity of the compounds was evaluated on a series of Gram-negative and Gram-positive bacterial strains. In particular, the neutral Au(I) and Pt(II) complexes showed significant antibacterial activity against Staphylococcus aureus and Enterococcus faecium at very low micromolar concentrations. The cytotoxicity against a range of eukaryotic cell lines was studied and revealed that the octahedral Ir(III) complex was non-toxic, while the square-planar Pt(II) and linear Au(I) complexes displayed non-selective micromolar activity. [ABSTRACT FROM AUTHOR]

This article presents a new method for synthesizing quinoxalines, a versatile class of compounds with applications in medicine, agriculture, and materials science. The authors demonstrate that their method, which uses meglumine sulfate as a catalyst, is simple, efficient, and produces high-quality products. The article includes experimental details and characterization data for the synthesized compounds, which include various quinoxaline derivatives. The document also includes acknowledgments and a disclosure statement. [Extracted from the article]

Adsorption of toxic substances is an important research field. In this work, the adsorption dynamics of halogenated and methylated benzenes onto hydroxylated silica upon photoexcitation has been investigated theoretically. The intermolecular interaction between the hydroxy (OH) group and the π electron density at the center of the benzene ring was also a major subject. In the ground state, the order of calculated adsorption energy was consistent with the OH⋅⋅⋅C bond strengths (SiO2–MeBe > SiO2–DimeBe > SiO2–BrBe > SiO2–ClBe > SiO2–FBe > SiO2–Be), implying this bond to be the major contributor to the adsorption. Upon photoexcitation to the first excited (S1) state by adsorbing shortwave-ultraviolet (UV), the OH⋅⋅⋅C bonds in each complex were strengthened with only the order of the bond strengths of SiO2–DimeBe and SiO2–MeBe reversed relative to the order in the ground state. In contrast to OH⋅⋅⋅C bonds, the OH⋅⋅⋅π bonds were all indicated to weaken upon photoexcitation. The results showed that the order of OH⋅⋅⋅π bond strengths in the S1 state to be SiO2–FBe > SiO2–BrBe > SiO2–DimeBe > SiO2–Be > SiO2–ClBe > SiO2–MeBe. However, the change in the corresponding adsorption energy was inconsistent with the order of OH⋅⋅⋅C bond strengths in the S1 state, due to the degree of weakening of the OH⋅⋅⋅π bond being greater than the degree of strengthening of the OH⋅⋅⋅C bonds. These changes were concluded to be induced by local excitation for each of the six complexes. This work has presented the photophysical dynamics of an adsorbent before and after photoexcitation. [ABSTRACT FROM AUTHOR]

Study of chemical properties of water radical cations is of great significance for elucidating related reactions process. In this paper, the reaction characteristics of (H2O)2+• prepared online with several benzene derivatives were investigated. The results showed that, when (H2O)2+• reacted with aromatic compounds without electron-withdrawing groups, such as benzene (C6H6, 78 u), anisole (C7H8O, 108 u) and 2,4-dimethylaniline (C8H11N, 121 u), the corresponding phenol product ((C6H5OH) +•, m/z 94), (C7H7O−OH)+•, m/z 124) and (C8H10NOH+H)+, m/z 138)) were observed, accompanied with the production of electron transfer (ET) products (C6H6) +•, (C7H8O) +•) or proton transfer (PT) product ((C8H11N+H)+). Isotope labeling experiments proved that OH in corresponding phenol products was originated from (H2O)2+•. Interestingly, when (H2O)2+• reacted with substituted benzenes bearing strong electron-withdrawing group, such as benzonitrile (C6H5CN, 103 u) and nitrobenzene (C6H5NO2, 123 u), the main products were the radical substituted adducts (C6H5CN+ H2O)+• (m/z 121) and (C6H5NO2+H2O)+• (m/z 141), respectively, without phenol products or substituted benzene radical cation were noticed. It was obvious that the reaction between (H2O)2+• and the substrate occurred through four competing processes: (a) electron transfer (ET) reaction, in which aromatic compounds release an electron to (H2O)2+• to from an aromatic radical cation; (b) proton transfer (PT) reaction in which aromatic compounds got a proton derived from the dissociation of (H2O)2+•; (c) dissociative electron transfer (DET) reaction, accompanied with the electron transfer process, C−H bond cleavage and C−OH bond formation; (d) radical substitution reaction in which a radical cation adduct consisting of aromatic molecule and H2O generates. It was speculated that the diverse reactivity of (H2O)2+• was owe to its two interchange structures ((H2O)H+−•OH and [H2O∴OH2]+•) generates. It was proposed that the electron withdrawing groups on the aromatic ring would benefit for the existence of two-center and three-electron structure of (H2O)2+• and induced the radical substitution reaction. In contrary, compounds without electron withdrawing groups or bearing electron donating groups on the aromatic ring would contribute to the presence of proton transfer structure of (H2O)2+• (containing H+ and •OH) and facilitate the C−OH bond formation. This study will help to elucidate the chemical reaction processes involving benzene or substituted benzenes and (H2O)2+•.

The application of supramolecular assembly (SA) with room temperature phosphorescence (RTP) in aqueous phase has the potential to revolutionize numerous fields. However, using simple molecules with crystalline RTP to construct SA with aqueous phase RTP is hardly possible from the standpoint of forces. The reason lies in that the transition from crystal to SA involves a structure transformation from highly stable to more dynamic state, leading to increased non‐radiative deactivation pathways and silent RTP signal. Here, with the benefit of the confinement from the layered double hydroxide (LDH), various simple molecules (benzene derivatives) can successfully form metastable SA with aqueous phase RTP. The maximum of RTP lifetime and efficiency can reach 654.87 ms and 5.02 %, respectively. Mechanistic studies reveal the LDH energy trap can strengthen the intermolecular interaction, providing the prerequisite for the existence of metastable SA and appearance of aqueous phase RTP. The universality of this strategy will usher exploration into other multifunctional monomer, facilitating the development of SAs with aqueous phase RTP. [ABSTRACT FROM AUTHOR]

In order to study the competition between halogen bond acceptor sites of multifunctional N,O,X-based halogen bond acceptors (X = S, O, N or π aromatic ring) we have synthesized a family of oxazole derivatives and cocrystallized them with selected iodoperfluorinated benzenes as halogen bond donors. Out of 28 combinations, 19 experiments yielded crystals suitable for single-crystal X-ray diffraction. Structural analysis revealed that in all of the obtained cocrystals the most prominent supramolecular interaction is the I⋯Noxazole halogen bond with relative shortening values of up to 18%, comparable to I⋯Npyridine halogen bond shortening values. The acceptors are ditopic in 10 cocrystals and form additional I⋯N, I⋯O or I⋯π halogen bonds. A majority of cocrystals feature one donor molecule per one acceptor molecule. In order to rank the acceptor sites and establish how the electrostatic potential differences impact the supramolecular landscape around these molecules, the values of molecular electrostatic potentials (MEPs) were calculated on their optimized geometries. These calculations were in agreement with experimental observations, since the best (most negative MEP value) acceptor binding site in the series of used oxazoles is the oxazole nitrogen atom. Depending on the difference between MEP values of the oxazole oxygen atom and the peripheral functionalities, additional halogen bonds could potentially be formed with one of these acceptor sites, leading to the formation of two different types of halogen-bonded supramolecular chains. [ABSTRACT FROM AUTHOR]

In this paper, we provide a highly accurate value for the binding energy of benzene to proton-ordered crystalline water ice (XIh), as a model for interstellar ices. We compare our computed value to the latest experimental data available from temperature-programmed desorption experiments and find that our binding energy value agrees well with data obtained from binding to either crystalline or amorphous ice. Importantly, our new value is lower than that used in most astrochemical networks by about nearly half its value. We explore the impact of this revised binding energy value for both an asymptotic giant branch (AGB) outflow and a protoplanetary disc. We find that the lower value of the binding energy predicted here compared with values used in the literature (4050 K versus 7587 K) leads to less depletion of gas-phase benzene in an AGB outflow, and leads to a shift outwards in the benzene snowline in the mid-plane of a protoplanetary disc. Using this new value, the AGB model predicts lower abundances of benzene in the solid phase throughout the outflow. The disc model also predicts a larger reservoir of gas-phase benzene in the inner disc, which is consistent with the recent detections of benzene for the first time in protoplanetary discs with JWST. [ABSTRACT FROM AUTHOR]

Although dearomative functionalizations enable the direct conversion of flat aromatics into precious three‐dimensional architectures, the case for simple arenes remains largely underdeveloped owing to the high aromatic stabilization energy. We herein report a dearomative sequential addition of two nucleophiles to arene π‐bonds through umpolung of chromium–arene complexes. This mode enables divergent dearomative carbonylation reactions of benzene derivatives by tolerating various nucleophiles in combination with alcohols or amines under CO‐gas‐free conditions, thus providing modular access to functionalized esters or amides. The tunable synthesis of 1,3‐ or 1,4‐cyclohexadienes as well as the construction of carbon quaternary centers further highlight the versatility of this dearomatization. Diverse late‐stage modifications and derivatizations towards synthetically challenging and bioactive molecules reveal the synthetic utility. A possible mechanism was proposed based on control experiments and intermediate tracking. [ABSTRACT FROM AUTHOR]

An efficient cyclization for the synthesis of 1,2,4,5-tetra-substituted benzenes via copper catalyzed dimerization of γ,δ-unsaturated ketones has been described. This one-pot procedure employs the γ,δ-unsaturated ketones as the sole substrate with multiple C–C bond formation. This protocol features broad substrate scope and provides a facile and robust method to construct polysubstituted benzene derivatives under mild conditions. [ABSTRACT FROM AUTHOR]

Melanin naturally exists in organisms and is synthetized by tyrosinase (TYR); however, its over-production may lead to aberrant pigmentation and skin conditions. Loquat (Eriobotrya japonica (Thunb.) Lindl.) flowers contain a variety of bioactive compounds, while studies on their suppressive capabilities against melanin synthesis are limited. Loquat flower isolate product (LFP) was obtained by ethanol extraction and resin purification, and its inhibitory efficiency against TYR activity was investigated by enzyme kinetics and multiple spectroscopy analyses. In addition, the impact of LFP on melanin synthesis-related proteins' expression in mouse melanoma B16 cells was analyzed using Western blotting. HPLC-MS/MS analysis indicated that LFP was composed of 137 compounds, of which 12 compounds, including flavonoids (quercetin, isorhamnoin, p-coumaric acid, etc.) and cinnamic acid and its derivatives, as well as benzene and its derivatives, might have TYR inhibitory activities. LFP inhibited TYR activity in a concentration-dependent manner with its IC50 value being 2.8 mg/mL. The inhibition was an anti-competitive one through altering the enzyme's conformation rather than chelating copper ions at the active center. LFP reduced the expression of TYR, tyrosinase-related protein (TRP) 1, and TRP2 in melanoma B16 cells, hence inhibiting the synthesis of melanin. The research suggested that LFP had the potential to reduce the risks of hyperpigmentation caused by tyrosinase and provided a foundation for the utilization of loquat flower as a natural resource in the development of beauty and aging-related functional products. [ABSTRACT FROM AUTHOR]

In this research, a novel and efficient nanocatalyst, namely, palladium immobilized onto 1,4-bis(pyrid-4-yl)benzene grafted to n-propyl-functionalized Fe3O4@MCM-41 nanoparticles (PBPBPMF), was synthesized and introduced. Then, its catalytic activity was tested in the synthesis of bis(pyrazolyl)methane (14 examples, 90–97%, 9–25 min, solvent-free, 60 °C) and biphenyl (13 examples, 80–98%, 10–120 min, PEG-400, 70 °C) derivatives. Bis(pyrazolyl)methane derivatives were synthesized via a one-pot pseudo-five-component reaction of aldehydes, ethyl acetoacetate, and phenylhydrazine, and biphenyl derivatives were obtained by a Stille coupling reaction. Transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDS), scanning electron microscopy (SEM), N2 sorption isotherms, vibrating sample magnetometer (VSM), inductively coupled plasma atomic emission spectrometer (ICP-OES), X-ray diffraction (XRD), thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FT-IR), and elemental mapping analyses were used to identify the catalyst. The PBPBPMF is a heterogeneous catalyst with several advantages, including a large specific surface area, ease of purification, and separation from the reaction mixture; furthermore, the nanocatalyst was recycled six times without appreciably altering its catalytic properties. [ABSTRACT FROM AUTHOR]

Organic electrochemistry is currently experiencing an era of renaissance, which is closely related to the possibility of carrying out organic transformations under mild conditions, with high selectivity, high yields, and without the use of toxic solvents. Combination of organic electrochemistry with alternative approaches, such as photo‐chemistry was found to have great potential due to induced synergy effects. In this work, we propose for the first time utilization of plasmon triggering of enhanced and regio‐controlled organic chemical transformation performed in photoelectrochemical regime. The advantages of the proposed route is demonstrated in the model amination reaction with formation of C−N bond between pyrazole and substituted benzene derivatives. Amination was performed in photo‐electrochemical mode on the surface of plasmon active Au@Pt electrode with attention focused on the impact of plasmon triggering on the reaction efficiency and regio‐selectivity. The ability to enhance the reaction rate significantly and to tune products regio‐selectivity is demonstrated. We also performed density functional theory calculations to inquire about the reaction mechanism and potentially explain the plasmon contribution to electrochemical reaction rate and regioselectivity. [ABSTRACT FROM AUTHOR]

Polyethylene terephthalate (PET) is one of the most abundant municipal polymer waste due to its widespread use in plastic industry. Therefore, its catalytic recycling into valuable products is of great interest. This study aims to achieve catalytic pyrolysis of PET into useful hydrocarbons. The pyrolysis of PET was carried out in the presence of aluminum in the temperature range of 450–650°C using a batch steel reactor, which resulted in wax, pyro-gases, and coke. The amount of wax was maximum at 500°C, whereas higher temperature favored formation of pyro-gases; however, pyrolysis oil formation was not observed. The gas chromatography mass spectrometric (GC-MS) analysis revealed that PET was degraded mainly into benzene derivatives through random scission of ester linkages. Knowing this fact, PET was copyrolized with polyethylene (which is readily convertible to pyrolysis oil) so as to increase aromatic hydrocarbons in pyrolysis oil by the interaction of degradation fragments of both polymers. The copyrolysis resulted in aromatics in the pyrolysis oil, which were further increased by the application of aluminum catalyst. Long chain paraffins were predominant in thermal pyrolysis oil with relatively higher amounts of carboxylic acids, alcohols, and ketones, which rendered the fuel heavier and acidic. In contrast, the catalytic pyrolysis oil contained lighter hydrocarbons with lower amount of acidic and oxygenated compounds, which could be attributed to enhanced scission and deoxygenation reactions by aluminum catalyst. The catalytic process also increased isoparaffins, olefins, and naphthenes in pyrolysis oil. These functionalities could further improve the fuel quality and combustion properties of pyrolysis oil. These findings have broader implications in terms of producing better fuel from waste plastics with the desirable fuel properties, as well as their mitigation from the environment. [ABSTRACT FROM AUTHOR]

In this study, we investigate the effect of terminal benzene derivatives in triphenylamine‐based oxime esters on their photoreactivity. Five novel oxime esters (Miko series) that containing different benzene derivatives as terminal groups, were synthesized. The electronic properties of the substituents on the benzene ring range from electron‐donating to electron‐withdrawing. Specifically, a methoxy benzene for Miko‐MOB, tert‐butyl benezene for Miko‐t‐Bu, chloro benzene for Miko‐CB, trifluoromethyl benzene for Miko‐TFM, and nitro benzene for Miko‐NB. Additionally, a compound with benzene only as the terminal substituent (TP‐1) was selected for comparision. All the new compounds exhibited higher molar extinction coefficients than TP‐1. Additionally, the steady‐state photolysis and electron spin resonance (ESR) properties would decrease from the electron‐donating substitutes to electron‐withdrawing substitutes. Finally, these oxime esters are utilized in Type I photoinitiating systems for the free radical polymerization of trimethylolpropane triacrylate (TMPTA) under UV or LED@405 nm light irradiation conditions. Among all formulations, Miko‐MOB demonstrated the highest double bond conversion efficiency under both UV and LED@405 nm light irradiation. Thus, terminal benzene derivatives in oxime esters play an important role in tuning the optical and photochemical reaction performance, offering significant value for the design strategy of such photoinitiators. [ABSTRACT FROM AUTHOR]

The article investigates the concentration of volatile organic compounds (VOC), particularly benzene and derivatives, in edible oils and the effects of heating duration on the behavior of these compounds using high-performance liquid chromatography. The study measures the concentrations of benzene and substituted benzenes in fresh mustard, cottonseed, rice bran and palm oils upon heating. It explores VOC emissions during deep frying with edible oils and its potential health risks.

The room temperature metal‐free cascade electrophilic addition/cyclization/oxidation reactions of (3‐phenoxyprop‐1‐yn‐1‐yl)benzenes to divergently synthesize various brominated benzopyran derivatives (3‐bromo‐2H‐chromenes, 3‐bromo‐2H‐chromen‐2‐ols and 3‐bromo coumarins) by tuning the amount of Br2 and H2O have been developed. The method exhibited high selectivity, mild reaction conditions, broad substrate scope, high efficiency, and the applicability for derivatization of the brominated products. The importance of the strategies provides a great advantage for selective synthesis of brominated benzopyran derivatives. [ABSTRACT FROM AUTHOR]

Background: The Pro-inflammatory mediators such as prostaglandin E2, nitric oxide and TNF-α are the key players in the stimulation of the inflammatory responses. Thus, the pro-inflammatory mediators are considered to be potential targets for screening nutraceutical with anti-inflammatory activity. Methods: In this context, we explored the anti-inflammatory potency of seagrass extract with western blot (Bio-Rad) analysis by using LPS induced RAW macrophages as in-vitro models, western blot analysis, In-silico methods using Mastero 13.0 software. Results: The anti-inflammatory activity of Seagrass was demonstrated through down regulation of Pro-inflammatory markers such as Cyclooxygenase-2, induced Nitric oxide synthase and prostaglandin E synthase-1. The results were validated by docking the phytochemical constituents of seagrass namely Isocoumarin, Hexadecanoic acid, and Cis-9 Octadecenoic acid, 1,2 Benzene dicarboxylic acid and beta-sitosterol with TNF-alpha, COX-2, iNOS and PGES-1. Conclusion: The methanolic extract of seagrass Halophila beccarii is a potential nutraceutical agent for combating against inflammation with a significant anti-inflammatory activity. [ABSTRACT FROM AUTHOR]

Excess molar volume, excess isentropic compressibility, deviation in viscosity and excess Gibbs free energy for the activation of viscous flow for binary mixtures of 2-methyl-2,4-pentanediol (MPD) with 1,2-dichlorobenzene (1,2-DCB), 1,3-dichlorobenzene (1,3-DCB) and 1,2,4-trichlorobenzene (1,2,4-TCB) components selected compositions are determined from the measured values of densities (ρ), speeds of sound (u) and viscosities (η) of pure components and their mixtures from 303.15 K to 313.15 K. The results are analysed in terms of intermolecular interactions or hydrogen bonding or hetero-association interactions in the binary mixtures. The Prigogine–Flory–Patterson (PFP) theory is applied to identify the predominant molecular interaction. The results of Jouyban–Acree model are discussed in terms of mean relative deviation (MRD) and individual relative deviation (IRD) between the calculated and experimental densities, speeds of sound and viscosities as accuracy criteria. [ABSTRACT FROM AUTHOR]

Study of chemical properties of water radical cations is of great significance for elucidating related reactions process. In this paper, the reaction characteristics of (H2O)2+• prepared online with several benzene derivatives were investigated. The results showed that, when (H2O)2+• reacted with aromatic compounds without electron-withdrawing groups, such as benzene (C6H6, 78 u), anisole (C7H8O, 108 u) and 2,4-dimethylaniline (C8H11N, 121 u), the corresponding phenol product ((C6H5OH) +•, m/z 94), (C7H7O−OH)+•, m/z 124) and (C8H10NOH+H)+, m/z 138)) were observed, accompanied with the production of electron transfer (ET) products (C6H6) +•, (C7H8O) +•) or proton transfer (PT) product ((C8H11N+H)+). Isotope labeling experiments proved that OH in corresponding phenol products was originated from (H2O)2+•. Interestingly, when (H2O)2+• reacted with substituted benzenes bearing strong electron-withdrawing group, such as benzonitrile (C6H5CN, 103 u) and nitrobenzene (C6H5NO2, 123 u), the main products were the radical substituted adducts (C6H5CN+ H2O)+• (m/z 121) and (C6H5NO2+H2O)+• (m/z 141), respectively, without phenol products or substituted benzene radical cation were noticed. It was obvious that the reaction between (H2O)2+• and the substrate occurred through four competing processes: (a) electron transfer (ET) reaction, in which aromatic compounds release an electron to (H2O)2+• to from an aromatic radical cation; (b) proton transfer (PT) reaction in which aromatic compounds got a proton derived from the dissociation of (H2O)2+•; (c) dissociative electron transfer (DET) reaction, accompanied with the electron transfer process, C−H bond cleavage and C−OH bond formation; (d) radical substitution reaction in which a radical cation adduct consisting of aromatic molecule and H2O generates. It was speculated that the diverse reactivity of (H2O)2+• was owe to its two interchange structures ((H2O)H+−•OH and [H2O∴OH2]+•) generates. It was proposed that the electron withdrawing groups on the aromatic ring would benefit for the existence of two-center and three-electron structure of (H2O)2+• and induced the radical substitution reaction. In contrary, compounds without electron withdrawing groups or bearing electron donating groups on the aromatic ring would contribute to the presence of proton transfer structure of (H2O)2+• (containing H+ and •OH) and facilitate the C−OH bond formation. This study will help to elucidate the chemical reaction processes involving benzene or substituted benzenes and (H2O)2+•. [ABSTRACT FROM AUTHOR]

Benzene is widely recognized as a potential carcinogen. Furthermore, the deficiency of specific nutrients may render individuals more vulnerable to cancer. For instance, β-cryptoxanthin, which possesses anti-inflammatory, antioxidant, and anticancer properties, has been identified as one such nutrient. Elevated benzene levels and reduced β-cryptoxanthin levels are reportedly correlated with an augmented susceptibility to cancer. To date, whether these 2 substances are linked with one another in the above correlation is yet to be determined. This study included 1358 participants with data on the serum concentration of β-cryptoxanthin as well as benzene and its derivatives. The data were sourced from the 2003–2004 National Health and Nutrition Examination Survey, a cross-sectional survey of the noninstitutionalized US population. Headspace solid-phase microextraction with gas chromatography and mass spectrometry was used to measure serum benzene and its derivatives, while high-performance liquid chromatography using multiwavelength photodiode-array absorbance detection was employed to quantify serum β-cryptoxanthin. In this study, male and female participants showed average β-cryptoxanthin levels of 9.10 ± 6.35 and 9.92 ± 8.95 ug/dL, respectively (p = 0.049). Styrene exhibited the strongest correlation with the change in β-cryptoxanthin concentration (β = −3.30, p for trend <0.001) upon comparing highest-quartile participants with those in the lowest quartile, followed by benzene (β = −2.95, p for trend <0.001), toluene (β = −2.90, p for trend <0.001), and ethylbenzene (β = −1.43, p for trend = 0.09). Subgroup analysis by sex displayed a statistically significant negative correlation of β-cryptoxanthin with benzene, styrene, and toluene in both the unadjusted and multivariate-adjusted models. The sera of noninstitutionalized US individuals exhibit a negative association of β-cryptoxanthin levels with benzene and its derivatives. Styrene demonstrates the strongest link with a substantial decline in serum β-cryptoxanthin levels, followed by benzene, toluene, and ethylbenzene. [ABSTRACT FROM AUTHOR]

Introduction: The increase in the incidence of allergic diseases is also caused by environmental conditions, including air pollution. In Europe and the USA, the incidence of food allergies is 6% and 8% of children, respectively. In 2023, the Chief Inspectorate of Environmental Protection (GIOŚ) stated that the air quality is much better compared to the previous 5 years. Aim: To determine the relationship between the level of atmospheric air pollution in Bielsko-Biala in 2018-2022 (nitrogen dioxide, suspended dust PM2.5 and PM10 and benzo(a)pyrene) and the incidence of food and skin allergies among children and adolescents from 0 to 18 years of age. Material and methods: Based on data from the Department of Health of the Silesian Voivodeship Office in Katowice, tables were prepared to illustrate the incidence of allergic contact dermatitis caused by substances introduced into the body (L 27) and allergic food inflammation of the stomach, small intestine and colon (K 52.2). In order to correlate the average annual concentrations of selected air pollutants and the incidence of food and skin allergies, the Statistica 13.6.0.064 (0616) program and Pearson correlation coefficients were used. Results: The incidence of food and skin allergies is decreasing and is 164.4/10,000 in 2018 and 150.6/10,000 in 2022 for food allergies and 197.3/10,000 in 2018 and 181.1/10,000 in 2022 for skin allergies. The average annual concentration of PM10 and benzo(a)pyrene is decreasing. Conclusions: In the analyzed time period, the discussed average annual concentrations of substances were not exceeded. The decreasing incidence of both food and skin allergies is related to the improvement in atmospheric air quality. [ABSTRACT FROM AUTHOR]

[Display omitted] • VOCs of PET at various recycling stages are identified by HS-SPME-GC-GC-qTOF-MS. • Chemometric analysis indicates the difference of PET at various recycling stages. • The elimination efficiency of FA obtained by HS-SPME reaches 100 %. • VOCs were primarily removed during the decontamination and melt-extrusion processes. The recycling of polyethylene terephthalate (PET) stands as an effective strategy for mitigating plastic pollution and reducing resource waste. The study aimed to investigate the characterization and elimination efficiency of volatile organic compounds (VOCs) present in rPET at various recycling stages using comprehensive two-dimensional gas chromatography-quadrupole-time-of-flight-mass spectrometry coupled with chemometrics. The results revealed that 52, 135, 95, 44, and 33 VOCs, mostly classified into three chemical groups, were tentatively identified in virgin − PET (v-PET), cold water washed − rPET (C-rPET), decontaminated − rPET (D-rPET), melt-extruded − rPET (M-rPET), and solid-state polycondensation − rPET (S-rPET), respectively. Regarding the VOCs with high and median detection frequencies, fatty acyls showed the highest elimination efficiency (100 % and 92 %), followed by organooxygen compounds (81 % and 99 %), others (97 % and 95 %), and benzene and substituted derivatives (82 % and 95 %) in term of HS-SPME. Following the recycling process, there was a general decrease in the concentration of almost all VOCs, as evidenced by the substantial reduction of o-Xylene, hexanoic acid, octanal, and D-limonene from 18.11, 22.43, 30.74, and 7.41 mg/kg to 0, 0, 3.97, and 0 mg/kg, respectively. However, it was noteworthy that the VOCs identified in the samples were not completely extracted, owing to the limitations of HS-SPME. Furthermore, chemometrics analysis indicated significant discrimination among VOCs from vPET, C-rPET, D-rPET, and M-rPET, while indistinct differences were observed between M-rPET and S-rPET. This study contributes to the enhancement of the recycling process and emphasizes the importance of safeguarding consumer health in terms of elimination of VOCs. [ABSTRACT FROM AUTHOR]

Biorefining of lignocellulosic biomass via a lignin first approach delivers a range of products with high oxygen content. Besides pulp, a lignin oil rich in guaiacols and syringols is obtained bearing multiple C(aryl)–OH and C(aryl)–OMe groups, typically named phenolics. Similarly, technical lignin can be used but is generally more difficult to process providing lower yields of monomers. Removal of the hydroxy and methoxy groups in these oxygenated arenes is challenging due to the inherently strong C–O bonds, in addition to the steric and electronic deactivation by adjacent –OH or –OMe groups. Moreover, chemoselective removal of a specific group in the presence of other similar functionalities is non-trivial. Other side-reactions such as ring saturation and transalkylation further complicate the desired reduction process. In this overview, three different selective reduction reactions are considered. Complete hydrodeoxygenation removes both hydroxy and methoxy groups resulting in benzene and alkylated derivatives (BTX type products) which is often complicated by overreduction of the arene ring. Hydrodemethoxylation selectively removes methoxy groups in the presence of hydroxy groups leading to phenol products, while hydrodehydroxylation only removes hydroxy groups without cleavage of methoxy groups giving anisole products. Instead of defunctionalization via reduction transformation of C(aryl)–OH, albeit via an initial derivatization into C(aryl)–OX, into other functionalities is possible and also discussed. In addition to methods applying guaiacols and syringols present in lignin oil as model substrates, special attention is given to methods using mixtures of these compounds obtained from wood/technical lignin. Finally, other important aspects of C–O bond activation with respect to green chemistry are discussed. [ABSTRACT FROM AUTHOR]

This article discusses the development of a biosensor called MopR for the detection of aromatic pollutants in drinking water. The researchers used synthetic biology to create an array of fluorescent sensor cells that can detect specific compounds at low levels. They also integrated quantitative estimation of pollutants with a portable imaging method for on-site monitoring. The biosensors have the potential to be a cost-effective and portable tool for detecting pollutants in drinking water, addressing a major global threat. [Extracted from the article]

Semen cryopreservation represents a promising technology utilized for preserving high-quality chicken varieties in husbandry practices. However, the efficacy of this methodology is significantly impeded by the diminished quality of sperm. Metabolites, as the end products of metabolic reactions, serve as indicators of biological processes and offer insights into physiological conditions. In this study, we investigaged the sperm quality and alteration in metabolic profiles during the cryopreservation of Longyou Partridge Chicken semen. Following artificial semen collection, four groups of semen samples were established based on four points of the cryopreservation process (Ⅰ, fresh semen; Ⅱ, semen added extender and chilled at 4 °C for 30 min; Ⅲ, semen added cryoprotectants; Ⅳ, semen gradient freezed and stored in liquid nitrogen). Semen cryopreservation has a negative effect on the percentage of sperm in a straight-line trajectory (LIN), has no significant effect on total motile sperms (TM) or the proportion of sperm with typical morphology (NM). Metabolites were identified using LC-MS technique and analyses including Principal Component Analysis (PCA), Orthogonal Partial Least Squares Discriminant Analysis (OPLS-DA), Univariate statistical analysis, and the Kyoto Encyclopedia of Genes and Genomes (KEGG) database were employed to identify metabolites. A total of 2471 metabolites had been identified, with the majority of the list being made up of amino acids and their metabolites as well as benzene and substituted derivatives. Group II exhibits 882 metabolites with significantly elevated abundance relative to Group I, alongside 37 metabolites displaying decreased abundance. In Group III, 836 metabolites demonstrate notably augmented abundance compared to Group II, while 87 metabolites exhibit reduced abundance. Furthermore, Group IV showcases 513 metabolites with markedly heightened abundance in comparison to Group III, and 396 metabolites with decreased abundance. Specific metabolites such as 5-Hydroxylysine, Phosphocholine, and alpha- d -glucose-6-phosphate exhibited a progressive decline during the cryopreservation process, correlating with either dilution and chilling, cryoprotectant addition, or freezing. In conclusion, our investigation systematically examined the changes of seminal metabolome and sperm quality throughout the cryopreservation process of rooster semen. • The alterations in metabolites during cryopreservation of rooster semen were investigated through four pivotal stages. • It demonstrates correlations between the semen metabolome and sperm quality. • Certain metabolites were newly found to decline progressively during semen cryopreservation. [ABSTRACT FROM AUTHOR]

Two hundred and twenty-three olive samples of different olive cultivars (Koroneiki, Asprolia, Lianolia, Ntopia, Thiaki, Mavrolia, and Others) grown in the Ionian islands (Kefalonia, Kerkyra, Leukada, and Zakynthos) were subjected to headspace solid phase microextraction coupled to gas chromatography/mass spectrometry analysis. The aim of the study was to characterize the aroma pattern of these olive oil cultivars, and track whether specific volatile compounds could be used for olive oil cultivar authentication using chemometrics. Multivariate analysis of variance implemented on the semi-quantitative data of volatile compounds (alcohols, aldehydes, benzene derivatives, esters, hydrocarbons, ketones, and terpenoids), showed that olive cultivar had a significant impact on the volatile composition of olive oil samples. Factor analysis and linear discriminant analysis indicated those specific volatile compounds that could be related to olive oil cultivar and established statistical models for the olive oil cultivar authentication from Ionian islands, thus indicating a characteristic aroma fingerprint of these olive oils. [ABSTRACT FROM AUTHOR]

Electrophilic aromatic nitrations are used for the preparation of a variety of synthetic products including dyes, agrochemicals, high energy materials, fine chemicals and pharmaceuticals. Traditional nitration methods use highly acidic and corrosive mixed acid systems which present a number of drawbacks. Aside from being hazardous and waste-producing, these methods also often result in poor yields, mostly due to low regioselectivity, and limited functional group tolerance. As a consequence, there is a need for effective and environmentally benign methods for electrophilic aromatic nitrations. In this work, the major aim was to develop reaction protocols that are more environmentally benign while also considering safety issues. The reactions were carried out in dilute aqueous nitric acid, and a broad range of experimental variables, such as acid concentration, temperature, time, and activation method, were investigated. Mesitylene and m-xylene were used as test substrates for the optimization. While the optimized reactions generally occurred at room temperature without any activation under additional solvent-free conditions, slight adjustments in acid concentration, stoichiometric equivalents, and volume were necessary for certain substrates, in addition to the activation. The substrate scope of the process was also investigated using both activated and deactivated aromatics. The concentration of the acid was lowered when possible to improve upon the safety of the process and avoid over-nitration. With some substrates we compared traditional and nontraditional activation methods such as ultrasonic irradiation, microwave and high pressure, respectively, to achieve satisfactory yields and improve upon the greenness of the reaction while maintaining short reaction times. [ABSTRACT FROM AUTHOR]