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Twelve compounds (1–12), kaempferol (1), luteolin (2), luteolin 4′-O-β-xyloside (3), luteolin 4′-O-β-glucoside (4), quercetin 4′-O-β-xyloside (5), kaempferol-3-O-[6″-O-(E)-p-coumaroyl]-β-D-glucoside (trans-tiliroside) (6), protocatechuic acid (7), gallic acid (8), methyl gallate (9), ethyl gallate (10), shikimic acid-3-O-gallate (11), and 3,3′,4′-tri-O-methyl-ellagic acid 4-sulfate (12), were isolated and identified from the aerial parts of Helianthemum cinereum (Cav.) Pers (synonym: Helianthemum rubellum C. Presl. All compounds were isolated by applying different chromatographic procedures, such as silica gel, RP-18 and Sephadex LH-20 columns. The structures were elucidated by extensive spectroscopic methods, mainly nuclear magnetic resonance NMR 1D and 2D, and mass spectrometry, as well as by comparison with the reported spectroscopic data. The two organic extracts, ethyl acetate (EtOAc) and butanol (BuOH), were evaluated for their potent phenolic and flavonoid contents using the Folin–Ciocalteu and aluminum chloride colorimetric methods. Furthermore, the antioxidant activity of the two extracts was determined using the DPPH, FRAP, and ABTS methods. Pure trans-tiliroside (6), the main isolated compound, and luteolin 4′-O-β-xyloside (3) were evaluated for their antitumor activity against the lung cancer (A549), melanoma (A375) and pancreatic cancer (Mia PaCa-2 and Panc-1) cell lines by MTT assay. [ABSTRACT FROM AUTHOR]

The Mediterranean basin is the leading worldwide region for olive production. Extreme weather is increasingly frequent in this region, and how these climate extremes will affect olive products and quality remains unknown. We aim to study the effects of the water deficit stress, which occurred in the summer of 2017, on olive fruit and oil quality from a 30-year-old orchard. Fruits from olive trees standing on (i) one hydrated and (ii) one dry area of an orchard at the north of Portugal were harvested. Fruits' water content, oil yield and quality, fruit carbohydrates, and fruit and oil phenolic metabolite profiles were analyzed. Fruits from the dry area presented low water availability and increased carbohydrates, oleuropein, oleoside, and elenolic acid glucoside abundance. Oil yield was lower in the dry area, but the abundance of oleacein increased, together with traits of some sensory sensations. Climate stress events can reduce oil yield but stimulate the accumulation of bioactive compounds that improve oil quality and nutritional value. [ABSTRACT FROM AUTHOR]

Obesity is a disease of epidemic proportions with a concerning increasing trend. Regarded as one of the main sources of energy, lipids can also represent a big part of an unnecessary intake of calories and be, therefore, directly related to the problem of obesity. Pancreatic lipase is an enzyme that is essential in the absorption and digestion of dietary fats and has been explored as an alternative for the reduction of fat absorption and consequent weigh loss. Literature describes a great variability of methodologies and experimental conditions used in research to evaluate the in vitro inhibitory activity of compounds against pancreatic lipase. However, in an attempt to choose the best approach, it is necessary to know all the reaction conditions and understand how these can affect the enzymatic assay. The objective of this review is to understand and summarize the methodologies and respective experimental conditions that are mainly used to evaluate pancreatic lipase catalytic activity. 156 studies were included in this work and a detailed description of the most commonly used UV/Vis spectrophotometric and fluorimetric instrumental techniques are presented, including a discussion regarding the differences found in the parameters used in both techniques, namely enzyme, substrate, buffer solutions, kinetics conditions, temperature and pH. This works shows that both UV/Vis spectrophotometry and fluorimetry are useful instrumental techniques for the evaluation of pancreatic lipase catalytic activity, presenting several advantages and limitations, which make the choice of parameters and experimental conditions a crucial decision to obtain the most reliable results. [ABSTRACT FROM AUTHOR]

An environment interacting with a quantum system can enhance transport through the suppression of quantum effects responsible for localization. In this paper, we study the interplay between bulk dephasing and a linear potential in a boundary-driven tight-binding chain. A linear potential induces Wannier-Stark localization in the absence of noise, while dephasing induces diffusive transport in the absence of a tilt. We derive an approximate expression for the steady-state current as a function of both dephasing and tilt which closely matches the exact solution for a wide range of parameters. From it, we find that the maximum current occurs for a dephasing rate equal to the period of Bloch oscillations in the Wannier-Stark localized system. We also find that the current displays a maximum as a function of the system size, provided that the total potential tilt across the chain remains constant. Our results can be verified in current experimental platforms and represents a step forward in analytical studies of environment-assisted transport. [ABSTRACT FROM AUTHOR]

Cancer remains one of the most critical global health issues. Conventional treatments, such as radiotherapy, surgery, or chemotherapy, have limitations, especially concerning side effects, resistance, and recurrence. Consequently, new innovative treatments to overcome these problems are needed. Photothermal therapy (PTT) is a promising alternative that uses photothermal agents that convert near-infrared light (NIR) into heat to kill cancer cells. Nanoparticles can be used as photothermal agents and also as drug delivery platforms, improving the drugs' stability, allowing for targeted delivery, and reducing toxicity. Due to its broad absorption band, high surface area, and versatility for surface functionalization, tungsten disulfide (WS2) has high potential in this context. This paper presents the state-of-the-art on the use of WS2-based materials to achieve effective and biocompatible new anticancer treatment strategies. [ABSTRACT FROM AUTHOR]

In patients with type 2 diabetes mellitus (DM), excessive gluconeogenesis is considered a major contributor to hyperglycemia. Therefore, targeting fructose 1,6‐bisphosphatase (FBPase), a key regulatory enzyme involved in gluconeogenesis, has gained interest as a potential therapeutic target for managing DM. In this study, a library of 42 structurally‐related chromone derivatives (including flavonoids, 2‐styrylchromones, and 2‐(4‐arylbuta‐1,3‐dien‐1‐yl)chromones, named as 2‐styrylchromone‐related derivatives), as well as 4‐ and 5‐styrylpyrazoles, were tested against human FBPase using a noncellular microanalysis screening system. Herbacetin, 3,4′,5,7,8‐pentahydroxyflavone, inhibited FBPase activity with an IC50 value of 6.4 ± 0.7 μM. The effects of herbacetin were also explored using an insulin‐resistant human hepatocellular carcinoma cell line (HepG2 cells). The results showed that herbacetin significantly decrease insulin resistance by promoting the phosphorylation of protein kinase B (Akt), and exhibited a capacity to ameliorate inflammation, evidenced by the modulation of the inhibitor of κB alpha (IκBα). This study provides important considerations for the design of novel FBPase inhibitors. Furthermore, it indicates a preliminary potential of herbacetin's dual action in improving insulin resistance and decreasing inflammation, suggesting the need for further investigation of this compound for addressing the complexities of type 2 DM management. [ABSTRACT FROM AUTHOR]

Two monoterpenoid lactones, loliolide (1) and epi-loliolide (2), were isolated from the crude dichloromethane extract of a microalga, Thalassiosira sp.). The structures of loliolide (1) and epi-loliolide (2) were elucidated by 1D and 2D NMR analysis, as well as a comparison of their 1H or/and 13C NMR data with those reported in the literature. In the case of loliolide (1), the absolute configurations of its stereogenic carbons were confirmed by X-ray analysis, whereas those of epi-loliolide (2) were determined by NOESY correlations. Loliolide (1) and epi-loliolide (2) were tested for their growth inhibitory activity against two Gram-positive (Staphylococcus aureus ATCC 29213, Enterococcus faecalis ATCC 29212) and two Gram-negative (Escherichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 27853) bacteria, as well as one clinical isolate (E. coli SA/2, an extended-spectrum β-lactamase producer-ESBL) and two environmental isolates, S. aureus 74/24, a methicillin-resistant (MRSA), and E. faecalis B3/101, a vancomycin-resistant (VRE) isolates. The results showed that none of the tested compounds exhibited antibacterial activity at the highest concentrations tested (325 μM), and both revealed low antioxidant activity, with ORAC values of 2.786 ± 0.070 and 2.520 ± 0.319 µmol TE/100 mg for loliolide (1) and epi-loliolide (2), respectively. [ABSTRACT FROM AUTHOR]

The olive tree is well adapted to the Mediterranean climate, but how orchards based on intensive practices will respond to increasing drought is unknown. This study aimed to determine if the application of a commercial biostimulant improves olive tolerance to drought. Potted plants (cultivars Arbequina and Galega) were pre-treated with an extract of Ascophyllum nodosum (four applications, 200 mL of 0.50 g/L extract per plant), and were then well irrigated (100% field capacity) or exposed to water deficit (50% field capacity) for 69 days. Plant height, photosynthesis, water status, pigments, lipophilic compounds, and the expression of stress protective genes (OeDHN1—protective proteins' dehydrin; OePIP1.1—aquaporin; and OeHSP18.3—heat shock proteins) were analyzed. Water deficit negatively affected olive physiology, but the biostimulant mitigated these damages through the modulation of molecular and physiological processes according to the cultivar and irrigation. A. nodosum benefits were more expressive under water deficit, particularly in Galega, promoting height (increase of 15%) and photosynthesis (increase of 34%), modulating the stomatal aperture through the regulation of OePIP1.1 expression, and keeping OeDHN1 and OeHSP18.3 upregulated to strengthen stress protection. In both cultivars, biostimulant promoted carbohydrate accumulation and intrinsic water-use efficiency (iWUE). Under good irrigation, biostimulant increased energy availability and iWUE in Galega. These data highlight the potential of this biostimulant to improve olive performance, providing higher tolerance to overcome climate change scenarios. The use of this biostimulant can improve the establishment of younger olive trees in the field, strengthen the plant's capacity to withstand field stresses, and lead to higher growth and crop productivity. [ABSTRACT FROM AUTHOR]

As a better alternative to lithium-ion batteries (LIBs), lithium–sulfur batteries (LSBs) stand out because of their multi-electron redox reactions and high theoretical specific capacity (1675 mA h g−1). However, the long-term stability of LSBs and their commercialization are significantly compromised by the inherently irreversible transition of soluble lithium polysulfides (LiPS) into solid short-chain S species (Li2S2 and Li2S) and the resulting substantial density change in S. To address these issues, we used activated carbon cloth (ACC) coated with Ni12P5 as a porous, conductive, and scalable sulfur host material for LSBs. ACC has the benefit of high electrical conductivity, high surface area, and a three-dimensional (3D) porous architecture, allowing for ion transport channels and void spaces for the volume expansion of S upon lithiation. Ni12P5 accelerates the breakdown of Li2S to increase the efficiency of active materials and trap soluble polysulfides. The highly effective Ni12P5 electrocatalyst supported on ACC drastically reduced the severity of the LiPS shuttle, affected the abundance of adsorption–diffusion–conversion interfaces, and demonstrated outstanding performance. Our cells achieved near theoretical capacity (>1611 mA h g−1) during initial cycling and superior capacity retention (87%) for >250 cycles following stabilization with a 0.05% decay rate per cycle at 0.2 C. [ABSTRACT FROM AUTHOR]

The Kröhnke Pyridine Synthesis has been discovered about six decades ago (1961), by Fritz Kröhnke and Wilfried Zecher at the University of Giessen. The original method involved the reaction of α‐pyridinium methyl ketone salts with α,β‐unsaturated carbonyl compounds in the presence of a nitrogen source, frequently ammonium acetate. Since its discovery, the Kröhnke methodology has been demonstrated to be suitable for the preparation of mono‐, di‐, tri‐ and tetra‐pyridines, with important applications in several research fields. Over the years, a number of modifications to the original approach have been developed and reported, enabling for the broad applicability of these methods even in modern days, also for the synthesis of non‐pyridine compounds. In this critical and tutorial review, we will thoroughly explore and discuss the potential of the original method, the refinements that have been made over the years, as well as some applications arising from each type of pyridine and/or non‐pyridine compounds produced by Kröhnke's approach. [ABSTRACT FROM AUTHOR]

Chalcones are a class of naturally occurring flavonoid compounds associated to a variety of biological and pharmacological properties. Several reviews have been published describing the synthesis and biological properties of a vast array of analogues. However, overviews on the reactivity of chalcones has only been explored in a few accounts. To fill this gap, a systematic survey on the most recent developments in the transition metal‐catalyzed transformation of chalcones was performed. The chemistry of copper, palladium, zinc, iron, manganese, nickel, ruthenium, cobalt, rhodium, iridium, silver, indium, gold, titanium, platinum, among others, as versatile catalysts will be highlighted, covering the literature from year 2000 to 2023, in more than 380 publications. [ABSTRACT FROM AUTHOR]

The Mediterranean will be one of the focal points of climate change. The predicted dry and hot summers will lead to water scarcity in agriculture, which may limit crop production and growth. The olive tree serves as a model woody plant for studying drought stress and improving water resource management; thus, it is critical to identify genotypes that are more drought tolerant and perform better under low irrigation or even rainfed conditions. In this study, the metabolomic approach was used to highlight variations in metabolites in stems and leaves of three Italian olive cultivars (previously characterized physiologically) under two and four weeks of drought stress. Phenolic and lipophilic profiles were obtained by gas chromatography-mass spectrometry and ultra-high performance liquid chromatography-mass spectrometry, respectively. The findings identified the leaf as the primary organ in which phenolic variations occurred. The Maurino cultivar exhibited a strong stress response in the form of phenolic compound accumulation, most likely to counteract oxidative stress. The phenolic compound content of ‘Giarraffa’ and ‘Leccino’ plants remained relatively stable whether they were exposed to drought or not. Variations in the lipid profile occurred in leaves and stems of all the cultivars. A high accumulation of compounds related to epicuticular wax components was observed in the leaf of ‘Giarraffa’, while a strong reduction of lipids and long-chain alkanes occurred in ‘Maurino’ when exposed to drought stress conditions. [ABSTRACT FROM AUTHOR]

Understanding the value of refinery by-products is crucial for assessing their potential in bitumen production. To achieve this task, the asphaltic residue, vacuum residue, and three different aromatic extracts obtained as by-products in the refining process of base oils have been characterized using various methods, including standard methods for bitumen grading (penetration, softening point, Fraass breaking point, and ageing stability), SARA analysis, proton nuclear magnetic resonance spectroscopy (1H NMR), and high-performance gel permeation chromatography (HP-GPC). Additionally, the penetration index and three significant colloidal indices based on SARA fractions have been calculated. The results show that the by-products possess distinct properties and chemical compositions. The most striking fact is that the asphaltic residue lacks saturates, while the three aromatic extracts lack asphaltenes. Due to different processing conditions, the two solvent-neutral (SN) type extracts were found to be similar, though distinct from the bright stock (BS) extract, which had a higher content of saturates and a lower content of aromatics. The comprehensive characterization of these by-products (residues and extracts) is essential for understanding their structure and planning their valorization in oil refineries, for example in the production of bitumens with specific properties. When combined with statistical and phenomenological modeling, the systematic analytical procedure presented here is useful for guiding the repurposing of oil refinery by-products. [ABSTRACT FROM AUTHOR]

This study seeks to increase the antifouling properties of fluorinated polyvinylidene (PVDF) membranes through the synergistic application of plasma treatment and polymer deposition, employing polymerizations of polyvinylpyrrolidone (PVP) and polyethyleneimine (PEI). The results show remarkable success in modifications, presenting exceptional performance. Two distinct surface modification methods, plasma treatment and polymer deposition, were used to improve the antifouling properties and filtration performance of PVDF membranes. The plasma used was a discharge dielectric barrier using ambient air as gas, and hydrophilic polymers, PVP, and PEI. The results outlined changes in membrane roughness with a significant roughness reduction of up to 43% evident based on topographic and morphological analyses. Hydraulic permeability analysis revealed a substantial 35‐fold increase, indicating a notable improvement in performance. All treated membranes exhibited higher water affinity and superior performance during 12‐h ultrafiltration compared to their untreated counterparts. After chemical cleaning, water flux recovery exceeded 85% for all treated membranes, indicating the inherent antifouling properties of the surface. [ABSTRACT FROM AUTHOR]

α-amylase and α-glucosidase are key enzymes implicated in carbohydrate digestion and their inhibition has been suggested as a powerful approach for regulating blood glucose levels. The present work describes for the first time their inhibition by a group of twelve hydroxylated 2-styrylchromones (2-SC). Our findings revealed that 2-SC display strong systematic inhibition of α-glucosidase rather than α-amylase activity. The number and position of the hydroxy groups in the chromone moiety further modulate the inhibitory profile of the studied compounds, and the derivatives bearing one catechol unit are efficient inhibitors of both enzymes. Enzyme kinetic studies indicate that all active compounds act as competitive inhibitors of α-amylase while most of them behave as non-competitive inhibitors of α-glucosidase. The results are promising and pave the way to further deciphering the potential of this class of compounds as a suitable alternative for the management of type 2 diabetes and its complications. [ABSTRACT FROM AUTHOR]

This article discusses the chemical composition and biological properties of Hedysarum pallidum, a plant species from the Fabaceae family. The study analyzes the compounds present in the butanol extract of Hedysarum pallidum using liquid chromatography and identifies various phenolic compounds. The extract was found to be rich in flavonoids, and the polar extract had the highest concentrations of phenolic and flavonoid compounds. The study also found that the extract showed antioxidant and α-glycosidase inhibitory activities, suggesting its potential for drug development. [Extracted from the article]

Non-melanoma skin cancer (NMSC) is one of the most common types of cancer worldwide. Despite the low mortality rate, rising incidence and recurrence rates are a burden on healthcare systems. Standard treatments such as chemotherapy, radiotherapy, and surgery are either invasive or toxic to healthy tissues; therefore, new, alternative, selective treatments are needed. In this work, a combined photothermal and chemotherapeutic approach is proposed. MoS2 was used as photothermal agent. It was prepared by a liquid-phase exfoliation and intercalation method using polyvinylpyrrolidone (PVP), followed by recirculation through a custom-built high-power ultrasonication probe. After 6 h of ultrasonication treatment, the average particle size was 165 ± 170 nm. Near-infrared (NIR) irradiation assays (810 nm, 0.1 W/cm2, 30 min, 180 J/cm2) confirmed that MoS2 nanosheets can efficiently convert NIR light into heat and reach 52 °C. The therapeutic doses of MoS2 (125 µg/mL) and Tegafur (50 µg/mL) were optimized and both were simultaneously incorporated into a Carbopol hydrogel. The cells were brought into contact with the hydrogel and irradiated with a custom-built NIR LED system. In HFF-1 cells (normal human fibroblasts), the metabolic activity was 78% (above the 70% toxicity limit—ISO 10993-5:2009(E)), while in A-431 skin cancer cells, it was 28%. In addition, the MoS2 + Tegafur hydrogels led to a 1.9-fold decrease in A-431 cancer cell metabolic activity, 72 h after irradiation, in comparison to MoS2 hydrogels, indicating a combined effect of photothermal and chemotherapy. [ABSTRACT FROM AUTHOR]

Since the beginning of the XXI century, Leishmaniasis has been integrated into the World Health Organization's list of the 20 neglected tropical diseases, being considered a public health issue in more than 88 countries, especially in the tropics, subtropics, and the Mediterranean area. Statistically, this disease presents a world prevalence of 12 million cases worldwide, with this number being expected to increase shortly due to the 350 million people considered at risk and the 2–2.5 million new cases appearing every year. The lack of an appropriate and effective treatment against this disease has intensified the interest of many research groups to pursue the discovery and development of novel treatments in close collaboration with the WHO, which hopes to eradicate it shortly. This paper intends to highlight the quinoline scaffold's potential for developing novel antileishmanial agents and provide a set of structural guidelines to help the research groups in the medicinal chemistry field perform more direct drug discovery and development programs. Thus, this review paper presents a thorough compilation of the most recent advances in the development of new quinoline-based antileishmanial agents, with a particular focus on structure–activity relationship studies that should be considerably useful for the future of the field. [ABSTRACT FROM AUTHOR]

Because of its considerable theoretical specific capacity and energy density, lithium–sulfur battery technology holds great potential to replace lithium-ion battery technology. However, a versatile, low-cost, and easily scalable bulk synthesis method is essential for translating bench-level development to large-scale production. This paper reports the design and synthesis of a new scalable sulfur cathode, S@CNT/PANI/PPyNT/TiO2 (BTX). The rationally chosen cathode components suppress the migration of polysulfide intermediates via chemical interactions, enhance redox kinetics, and provide electrical conductivity to sulfur, rendering outstanding long-term cycling performance and strong initial specific capacity in terms of electrochemical performance. This cathode's cell demonstrated an initial specific capacity of 740 mA h g−1 at 0.2 C (with a capacity decay rate of 0.08% per cycle after 450 cycles). [ABSTRACT FROM AUTHOR]

Brown macroalgae are rich sources of nutrients and health-promoting compounds. Nevertheless, their consumption is still limited by their strong organoleptic characteristics, thus requiring the development of extraction strategies to profit from their nutritional value. To fulfil this, two sequential extraction approaches were developed, differing in the solvent used in the first extraction step, water in approach 1 or food-grade ethanol in approach 2, to obtain economic and affordable extracts rich in specific compounds from Fucus vesiculosus. The use of water in the first step of extraction allowed us to recover water-soluble phlorotannins, laminarans and mannuronic-rich alginates, making the subsequent 70% ethanol extract richest in fucoxanthin (0.07% algae DW), and the hot water fractions purest in fucoidans and alginates with a lower mannuronic-to-guluronic (M/G) ratio (2.91). Conversely, when beginning extraction procedures with 96% ethanol, the recovered yields of phlorotannins increased (0.43 g PGE/100 g algae DW), but there was a concomitant seven-fold decrease in the recovery of fucoxanthin in the subsequent 70% ethanol extract. This approach also led to less pure hot water fractions containing fucoidans, laminarans and alginates with a higher M/G ratio (5.50). Overall, this work unveiled the potential of the first extraction steps in sustainable and holistic cascade strategies to modulate the composition of food-grade extracts, creating prospects of their application as tailored functional ingredients in food products. [ABSTRACT FROM AUTHOR]

Palladium nanohybrids were synthesized and applied to the one‐pot synthesis of bis(3‐indolyl)methanes by selective C−C bond reaction from benzyl alcohol and indole. A T. lanuginosus lipase‐palladium nanoparticles hybrid (Pd@TLL) was synthesized, yielding PdNPs with an average diameter size of 5 nm. This heterogeneous catalyst was first tested in the selective oxidation of benzyl alcohol to benzaldehyde in different solvents. Then, the direct formation of bis(3‐indolyl)methane, by in situ oxidation and C−C coupling, was successfully evaluated under different conditions, obtaining >99 % conversion at 80 °C in toluene, with a TOF value of 9 min−1 and 89 % in pure water, demonstrating the versatility of these biohybrids. [ABSTRACT FROM AUTHOR]

Type 2 diabetes mellitus (DM) continues to escalate, necessitating innovative therapeutic approaches that target distinct pathways and address DM complications. Flavonoids have been shown to possess several pharmacological activities that are important for DM. This study aimed to evaluate the in vivo effects of the flavonoid melanoxetin using Goto-Kakizaki rats. Over a period of 14 days, melanoxetin was administered subcutaneously to investigate its antioxidant, anti-inflammatory, and antidiabetic properties. The results show that melanoxetin reduced insulin resistance in adipose tissue by targeting protein tyrosine phosphatase 1B. Additionally, melanoxetin counteracted oxidative stress by reducing nitrotyrosine levels and modulating superoxide dismutase 1 and hemeoxygenase in adipose tissue and decreasing methylglyoxal-derived hydroimidazolone (MG-H1), a key advanced glycation end product (AGE) implicated in DM-related complications. Moreover, the glyoxalase 1 expression decreased in both the liver and the heart, correlating with reduced AGE levels, particularly MG-H1 in the heart. Melanoxetin also demonstrated anti-inflammatory effects by reducing serum prostaglandin E2 levels, and increasing the antioxidant status of the aorta wall through enhanced acetylcholine-dependent relaxation in the presence of ascorbic acid. These findings provide valuable insights into melanoxetin's therapeutic potential in targeting multiple pathways involved in type 2 DM, particularly in mitigating oxidative stress and glycation. [ABSTRACT FROM AUTHOR]

Non-fullerene acceptor materials have posed new paradigms for the design of organic solar cells , whereby efficient carrier generation is obtained with small driving forces, in order to maximize the open-circuit voltage (VOC). In this paper, we use a coarse-grained mixed quantum–classical method, which combines Ehrenfest and Redfield theories, to shed light on the charge generation process in small energy offset interfaces. We have investigated the influence of the energetic driving force as well as the vibronic effects on the charge generation and photovoltaic energy conversion. By analyzing the effects of the Holstein and Peierls vibrational couplings, we find that vibrational couplings produce an overall effect of improving the charge generation. However, the two vibronic mechanisms play different roles: the Holstein relaxation mechanism decreases the charge generation, whereas the Peierls mechanism always assists the charge generation. Moreover, by examining the electron–hole binding energy as a function of time, we evince two distinct regimes for the charge separation: the temperature independent excitonic spread on a sub-100 fs timescale and the complete dissociation of the charge-transfer state that occurs on the timescale of tens to hundreds of picoseconds, depending on the temperature. The quantum dynamics of the system exhibits the three regimes of the Marcus electron transfer kinetics as the energy offset of the interface is varied. [ABSTRACT FROM AUTHOR]

Developing Piping and Instrumentation Diagrams (P&IDs) is a crucial step during process development. We propose a data‐driven method for the prediction of control structures. Our methodology is inspired by end‐to‐end transformer‐based human language translation models. We cast the control structure prediction as a translation task where Process Flow Diagrams (PFDs) without control structures are translated to PFDs with control structures. We represent the topology of PFDs as strings using the SFILES 2.0 notation. We pretrain our model using generated PFDs to learn the grammatical structure. Thereafter, the model is fine‐tuned leveraging transfer learning on real PFDs. The model achieved a top‐5 accuracy of 74.8% on 10,000 generated PFDs and 89.2% on 100,000 generated PFDs. These promising results show great potential for AI‐assisted process engineering. The tests on a dataset of 312 real PFDs indicate the need for a larger PFD dataset for industry applications and hybrid artificial intelligence solutions. [ABSTRACT FROM AUTHOR]

SFILES are a text-based notation for chemical process flowsheets. They were originally proposed by d'Anterroches (Process flow sheet generation & design through a group contribution approach) who was inspired by the text-based SMILES notation for molecules. The text-based format has several advantages compared to flowsheet images regarding the storage format, computational accessibility, and eventually for data analysis and processing. However, the original SFILES version cannot describe essential flowsheet configurations unambiguously, such as the distinction between top and bottom products. Neither is it capable of describing the control structure required for the safe and reliable operation of chemical processes. Also, there is no publicly available software for decoding or encoding chemical process topologies to SFILES. We propose the SFILES 2.0 with a complete description of the extended notation and naming conventions. Additionally, we provide open-source software for the automated conversion between flowsheet graphs and SFILES 2.0 strings. This way, we hope to encourage researchers and engineers to publish their flowsheet topologies as SFILES 2.0 strings. The ultimate goal is to set the standards for creating a FAIR database of chemical process flowsheets, which would be of great value for future data analysis and processing. [ABSTRACT FROM AUTHOR]

The escalating production of processed prickly pear products has led to a substantial rise in waste materials, particularly peel, which is rich in bioactive chemicals and holds the potential for value-added product development. However, the high perishability of these peels imposes effective preservation techniques. So, this work aimed to explore the potential of prickly pear peels from O. ficus-indica 'Rossa', 'Gialla', and 'Bianca' cultivars for the production of Opuntia beverages, namely infusions. To achieve this goal, two distinct drying methods, namely microwave drying and a food dehydrator, were employed with the latter method, resulting in the higher recovery of phenolic compounds (0.5 mgGAE/mL vs. 0.16 mgGAE/mL) and the higher antioxidant capacity of the resulting infusions. Additionally, various steeping conditions involving water temperatures of 80, 90, and 100 °C were assessed to maximize the levels of phenolic compounds and antioxidant activity. The results demonstrate that the better overall drying method temperature and steeping conditions for the food dehydrator were at 35 °C and boiling water (100 °C) due to its generally better results and practicality. Sensorial trials revealed that the three infusions were generally accepted (score > 7.20 out of 9) but that O. ficus-indica 'Rossa' received the highest ratings. This study offers valuable insights for optimizing drying methods and steeping conditions to preserve and enhance the bioactive compounds and antioxidant potential in prickly pear peel infusions, promoting their sustainable utilization as functional ingredients in food and nutraceutical applications. [ABSTRACT FROM AUTHOR]

This article discusses the application of the Heck reaction for the synthesis of C-glycosyl phenolic compounds. The authors successfully synthesized C-glycosylated 2-styrylchromones and xanthones with high stereoselectivity. The article also includes detailed experimental procedures and characterization data for the synthesized compounds. The given text appears to be a scientific article or research paper that includes data related to chemical compounds. The text provides information about the chemical structure and properties of different compounds, including their nuclear magnetic resonance (NMR) spectra, mass spectrometry data, and physical characteristics. The compounds mentioned in the text are described in terms of their chemical composition, yield, and various spectroscopic data. [Extracted from the article]

Artur Silva's research group has a long history in the field of medicinal chemistry. The development of new synthetic methods for oxygen (mostly polyphenols, e.g., 2- and 3-styrylchromones, xanthones, flavones) and nitrogen (e.g., pyrazoles, triazoles, acridones, 4-quinolones) heterocyclic compounds in order to be assessed as antioxidant, anti-inflammatory, antidiabetic, and anticancer agents has been the main core work of our research interests. Additionally, the synthesis of steroid-type compounds as anti-Alzheimer drugs as well as of several chromophores as important dyes for cellular imaging broadened our research scope. In this review article, we intend to provide an enlightened appraisal of all the bioactive compounds and their biological properties that were synthesized and studied by our research group in the last two decades. [ABSTRACT FROM AUTHOR]

Adenanthera pavonina is a medicinal species, which economic value depends on the richness of its phytocompounds. Extreme climatic conditions are becoming frequent worldwide, but despite their impact on plant productivity these weather events also modulate plants' metabolism increasing the production of important phytocompounds. We aimed to characterize the physiological and metabolite adjustments in A. pavonina leaves induced by drought and UV-B radiation. Plants were exposed to drought (DS), UV-B radiation (UV-B), and drought + UV-B (DS + UV-B), and photosynthesis, lipophilic metabolites, and antioxidant status were evaluated. The stress conditions compromised the photosynthetic performance and induced oxidative stress (DS and UV-B plants). However, plants activated protective mechanisms (increased antioxidant activity and flavonoids in all treatments, total phenols in DS and DS + UV-B, and catechols in UV-B and DS + UV-B) and modulated their lipophilic profiles (accumulation of fatty acids and TCA cycle-related metabolites, and reduction of carbohydrates) to cope with the stress. We demonstrate for the first time that DS and UV-B radiation can enrich A. pavonina leaves with antioxidants and fatty acids increasing their medicinal value. [ABSTRACT FROM AUTHOR]

Keywords: manganese; nickel; palladium; bimetallic catalysis; indole; oxidation; C-H activation EN manganese nickel palladium bimetallic catalysis indole oxidation C-H activation 3625 3631 7 10/19/23 20231102 NES 231102 Graph I N i -Heterocyclic scaffolds are crucial in synthetic and medicinal chemistry. Subsequently, imine formation and C-H activation reaction were carried out and indole B 5a b was isolated in 19% total yield (76% yield was obtained in the C-H activation step). The filtration step seems to be crucial for the Pd-catalyzed C-H activation reaction, indicating that the presence of the Ni catalyst to a great extent inhibited the Pd-catalyzed reaction leading to a poor overall yield of the indole B 5a b . In the case of I m i -(trifluoromethyl)aniline ( B 3c b ), its corresponding imine B 4c b underwent cyclization at the less-hindered position affording 6-substituted indole B 5c b in 34% yield (yield from last step). [Extracted from the article]

In modern aviation production, innovative hard-to-machine materials with unique physical and mechanical properties are being used increasingly. When processing such materials, the weakest link in the technological chain of production is the metal-cutting tool. In this paper, to improve the efficiency of the blade cutting of heat-resistant alloys, we propose the use of nanostructured multilayer wear-resistant coatings with subsequent laser processing of the cutting surfaces of the end milling cutters according to various schemes. In this case, an increase in the wear-resistant properties of the cutting edge by 15%–20% is provided due to the formation, at high temperatures, of secondary structures with increased wear resistance and a reduction of the temperature and force loading of contact processes. Methodologically, the work was carried out in several consecutive stages: the first stage was the determination of effective grades of wear-resistant coatings obtained via various installations with their subsequent laser processing during the «SharpMark™ Fiber» installation; at the second stage tribotechnical tests were carried out during the tribometer and adhesion installation; and in the third stage wear-resistant, temperature-force tests were carried out using milling machines in various cutting modes. According to the results of the field tests, the tool durability period was increased by 15%–20%. [ABSTRACT FROM AUTHOR]

The effective utilization of luminescent dyes often relies on a comprehensive understanding of their excitation and relaxation pathways. One such pathway, Excited‐State Proton Transfer (ESPT), involves the tautomerization of the dye in its excited state, resulting in a new structure that exhibits distinct emission properties, such as a very large Stokes′ shift or dual‐emission. Although the ESPT phenomenon is well‐explained theoretically, its experimental demonstration can be challenging due to the presence of numerous other phenomena that can yield similar experimental observations. In this review, we propose that an all‐encompassing methodology, integrating experimental findings, computational analyses, and a thorough evaluation of diverse mechanisms, is essential for verifying the occurrence of ESPT in luminescent dyes. Investigations have offered significant understanding of the elements impacting the ESPT process and the array of approaches that can be used to validate the existence of ESPT. These discoveries hold crucial ramifications for the advancement of molecular probes, sensors, and other applications that depend on ESPT as a detection mechanism. [ABSTRACT FROM AUTHOR]

New series of quinoline coupled to diversely functionalized heterocyclic cores were synthesized, via appropriate synthetic routes, using 3-(quinolin-3-yl) oxirane-2,2-carbonitriles as key intermediates. The epoxide ring opening gave bi-heterocyclic hybrids such as α-quinolin-3-yl-α-aminoacetic acid derivatives, quinoxaline- and benzimidazole-quinoline hybrids, and quinoline-1,-3-oxathioles. Some selected bi-heterocyclic hybrids were evaluated in vitro for their antioxidant potential using DPPH* and ABTS*+ methods, and their anti- fungal activity against Fusarium oxysporum f. sp. Lycopersici. It was demon- strated that bi-heterocyclic aromatic systems exhibited significant antioxidant activities, which are similar in magnitude to those of standards BHT and BHA with important IC50 values. The SAR study of the antifungal activity revealed that only compounds bearing a 2-imino-1,3-oxathiole nucleus are active show- ing interesting results. Crystal X-ray structures for two compounds are also reported. [ABSTRACT FROM AUTHOR]

Osteosarcoma (OS) is a common childhood sarcoma, and its treatment is hindered by adverse effects, chemoresistance, and recurrence. Interleukin (IL)-6 production by tumors plays a significant role in inflammation, carcinogenesis, and metastasis. This study aimed to investigate the antiproliferative potential of luteolin derivatives in OS and to evaluate interleukin production. MG-63, Saos-2, HOS, and 143B human OS cell lines were incubated with luteolin and eight derivatives containing hydroxy, chlorine, or alkyl substitutions. The cell viability and growth were evaluated in the presence of these compounds. Apoptosis was also examined through the analysis of the Bax expression and caspase-3 activity. Finally, the gossypetin effects were measured regarding the production of proinflammatory cytokines interleukin (IL)-6, IL-1β, and IL-12p70. Our findings show that gossypetin was the most potent compound, with proliferation-suppressing activities that induced a series of critical events, including the inhibition of the cell viability and growth. Apoptosis was associated with enhanced caspase-3 activity and increased Bax expression, indicating the involvement of the intrinsic pathway of apoptosis. Moreover, pre-/co-treatment with gossypetin significantly reduced the autocrine production of proinflammatory cytokines. Further investigation is required; nevertheless, considering the link between inflammation, carcinogenesis, and metastasis in OS, our findings suggest that gossypetin exhibits anti-proliferative and anti-inflammatory properties that are potentially relevant in the clinical context. [ABSTRACT FROM AUTHOR]

Billroth-I (B-I) anastomosis is known as a simple and physiological reconstruction method after distal subtotal gastrectomy for early gastric cancer. Yet its role and oncological validity in non-early gastric adenocarcinoma (NEGA) remain unclear. Patients with NEGA without distant metastases operated between May 2004 and December 2020 were included. Surgical and oncologic outcomes of distal subtotal gastrectomy were studied in patients with B-I and Billroth II (B-II) anastomoses. Propensity score matching (PSM) was used to adjust for age, gender, tumor size, location, resection type, pT and pN stages. A total number of 332 patients underwent distal subtotal gastrectomy for NEGA followed by B-I and B-II anastomoses in 165 (49.7%) and 167 (50.3%) cases, respectively. B-I was applied in patients with smaller tumor size, less advanced pT stage and tumor location in the gastric antrum. The former was also associated with lower proportion of multiorgan resections and shorter operative time. After PSM, these differences became statistically non-significant, except operative time. Postoperative outcomes were similar before and after PSM. Greater lymph node yield was observed in patients with B-I anastomosis. The incidence of recurrence, specifically local recurrence was lower in patients with B-I anastomosis. However, this association was not statistically significant in the multivariable model. Median overall survival was 38 months, without significant differences between the groups. The use of B-I anastomosis after distal subtotal gastrectomy for NEGA is associated with satisfactory surgical and oncologic outcomes. B-I anastomosis should be considered as a valid reconstruction method in these patients. [ABSTRACT FROM AUTHOR]

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The recent developments of multicomponent reactions for the synthesis of biologically active molecules containing the pyrazole moiety were reviewed by J.-C. Castillo and coworkers. They reported on the main methods of synthesis, which include Friedländer condensation, synthesis from anthranilic acid derivatives, multicomponent synthesis, and others, and the use of this class of compounds as potential fluorescent sensors and biologically active compounds. Pyrazole and its derivatives are considered privileged I N i -heterocycles with immense therapeutic potential. They also reported synthetic methods used for their synthesis, starting from a pre-formed pyrazole or pyridine, as well as the biomedical applications of such compounds. [Extracted from the article]

Simple Summary: The in vitro antiprotozoal activity of Hibiscus sabdariffa ethanolic extract was evaluated on the ciliate parasite Philasterides dicentrarchi, which causes severe losses in turbot aquaculture. Our results showed that H. sabdariffa extract had successfully inhibited the parasite population growth rate (IC50 = 1.57 mg mL−1), and caused significant changes in the activity of antioxidant enzymes (LOEC = 0.22 mg mL−1), especially glutathione peroxidase, total glutathione, and catalase. The activity of proteases (virulence factors) was also inhibited (IC50 = 0.76 mg mL−1), and the gene expression of catepsin 90 and leishmanolysin proteases was downregulated. Organic acids and phenolic phytochemicals in hibiscus extract are potentially responsible for the antiprotozoal bioactivity herein determined. Therefore, H. sabdariffa extract can be a promising disease-control alternative against the ciliate proliferation, cellular defense mechanisms, and pathogenicity. Philasterides dicentrarchi is an histophagous parasite that infects flatfish, namely turbot (Scophthalmus maximus), and cause significant losses in aquaculture units. The available measures for P. dicentrarchi control have limited efficiency, and some cause harm to fish. Hence, sustainable and natural control strategies are urgently needed. This study evaluated the in vitro bioactivity of the ethanol extract of Hibiscus sabdariffa calyces on P. dicentrarchi population growth rate (PGR), oxidative stress biomarkers (glutathione-S-transferases (GST), glutathione reductase (GR), glutathione peroxidase (GPx), total glutathione (TG) and catalase (CAT), neurotoxicity (acetylcholinesterase, AChE), activity and gene expression of proteases as major virulence factors. H. sabdariffa extract inhibited parasite PGR (IC50 = 1.57 mg mL−1), and caused significant changes in the activity of antioxidant enzymes (LOEC = 0.22 mg mL−1), especially GPx, TG, and CAT. The activity of proteases was also severely inhibited (IC50 = 0.76 mg mL−1), and gene expression of catepsin 90 and leishmanolysin proteases was downregulated. Organic acids and phenolic phytochemicals in hibiscus extract are potentially responsible for the antiprotozoal bioactivity herein determined. Therefore, H. sabdariffa extract can be a promising disease-control alternative against the ciliate proliferation, cellular defense mechanisms and pathogenicity. Still, its applicability in aquaculture settings, and potential effects on farmed fish, should be further elucidated. [ABSTRACT FROM AUTHOR]

Five undescribed pentaketide derivatives, (R)-6,8-dihydroxy-4,5-dimethyl-3-methylidene-3,4-dihydro-1H-2-benzopyran-1-one (1), [(3S,4R)-3,8-dihydroxy-6-methoxy-4,5-dimethyl-1-oxo-3,4-dihydro-1H-isochromen-3-yl]methyl acetate (2), (R)-5, 7-dimethoxy-3-((S)-(1-hydroxyethyl)-3,4-dimethylisobenzofuran-1(3H)-one (4b), (S)-7-hydroxy-3-((S)-1-hydroxyethyl)-5-methoxy-3,4-dimethylisobenzofuran 1(3H)-one (5), and a p-hydroxyphenyl-2-pyridone derivative, avellaneanone (6), were isolated together with the previously reported (R)-3-acetyl-7-hydroxy-5-methoxy-3,4-dimethylisobenzofuran-1(3H)-one (3), (R)-7-hydroxy-3-((S)-1-hydroxyethyl)-5-methoxy-3,4-dimethylisobenzofuran-1(3H)-one (4a) and isosclerone (7), from the ethyl acetate extract of a culture of a marine sponge-derived fungus, Hamigera avellanea KUFA0732. The structures of the undescribed compounds were elucidated using 1D and 2D NMR, as well as high-resolution mass spectral analyses. The absolute configurations of the stereogenic carbons in 1, 4b, 5, and 6 were established by X-ray crystallographic analysis. The absolute configurations of C-3 and C-4 in 2 were determined by ROESY correlations and on the basis of their common biosynthetic origin with 1. The crude fungal extract and the isolated compounds 1, 3, 4b, 5, 6, and 7 were assayed for their growth inhibitory activity against various plant pathogenic fungi viz. Alternaria brassicicola, Bipolaris oryzae, Colletotrichum capsici, C. gloeosporiodes, Curvularia oryzae, Fusarium semitectum, Lasiodiplodia theobromae, Phytophthora palmivora, Pyricularia oryzae, Rhizoctonia oryzae and Sclerotium rolfsii. [ABSTRACT FROM AUTHOR]

2-Styrylchromones (2-SCs) are interesting compounds for their biological properties as well as versatility as starting materials for further transformations. Herein, we disclose a new 2-SC derivative—2,2'-[(1E,1'E)-{[hexa-2,4-diyne-1,6-diylbis(oxy)]bis(2,1-phenylene)}bis(ethene-2,1-diyl)]bis(4H-chromen-4-one)—which is a dimeric compound formed by two units of 2-SC linked through a 1,3-diyne moiety. It was obtained in excellent yield (96%) through the copper-catalyzed homocoupling of two molecules of O-propargyl-2-SC. Its structure was unveiled by 1D (1H and 13C) and 2D (HSQC and HMBC) NMR techniques together with HRMS. [ABSTRACT FROM AUTHOR]

Risk factors for disease recurrence following curative resection for locally advanced colon cancer (LACC) remain unclear as conflicting results have been reported in the literature. The aim of this study was to examine these factors in the setting of developing country's health care system affected by limited accessibility to the multimodal cancer treatment. Patients who had undergone curative colon resection for LACC between 2004 and 2018 were included. Data were obtained from a prospectively maintained database. Factors associated with disease recurrence, types of recurrence and recurrence-free survival were studied. A total of 118 patients with LACC were operated within the study period. Median follow-up was 36 (2-147) months. Adjuvant therapy was used in 41 (34.7%) patients and 62 (52.5%) were diagnosed with recurrence. In the multivariable analysis, disease recurrence was associated with tumor and nodal stages, as well as with the lymph node yield. Local recurrence, distant metastases, and peritoneal carcinomatosis were observed in 8 (6.8%), 30 (25.4%), and 24 (20.3%) patients, respectively. Early recurrence was diagnosed in 27 (22.9%) cases with peritoneal carcinomatosis being its most common type. Preoperative serum CA 19–9 levels, tumor, and nodal stages were linked to recurrence-free survival in the univariable analysis. Only tumor stage remained such in the multivariable model. Our findings suggest that lymph node yield, tumor, and nodal stages are associated with recurrence following curative resection for LACC. [ABSTRACT FROM AUTHOR]