Dielectric profile at the Pt(111)/water interface.

The dielectric constant, although a simplified concept when considering atomic scales, enters many mean-field, electrochemical interface models and constant potential models as an important parameter. Here, we use ab initio and machine-learned molecular dynamics to scrutinize the behavior of the electronic contribution to ɛr(z) as a function of distance z from a Pt(111) surface. We show that the resulting dielectric profile can largely be explained as a sum of the metallic response and the density-scaled water response at the interface.

Open-boundary molecular dynamics of ultrasound using supramolecular water models.

Ultrasound can be used to manipulate protein function and activity, as well as for targeted drug delivery, making it a powerful diagnostic and therapeutic modality with wide applications in sonochemistry, nanotechnology, and engineering. However, a general particle-based approach to ultrasound modeling remains challenging due to the significant disparity between characteristic time scales governing ultrasound propagation. In this study, we use open-boundary molecular dynamics to simulate ultrasound waves in liquid water under ambient conditions by employing supramolecular water models, i.

Combining Photochemical Oxyfunctionalization and Enzymatic Catalysis for the Synthesis of Chiral Pyrrolidines and Azepanes.

Chiral heterocyclic alcohols and amines are frequently used building blocks in the synthesis of fine chemicals and pharmaceuticals. Herein, we report a one-pot photoenzymatic synthesis route for -Boc-3-amino/hydroxy-pyrrolidine and -Boc-4-amino/hydroxy-azepane with up to 90% conversions and >99% enantiomeric excess. The transformation combines a photochemical oxyfunctionalization favored for distal C-H positions with a stereoselective enzymatic transamination or carbonyl reduction step.

Origins of the Superiority of Oscillating Electric Fields for Disrupting Senile Plaques: Insights from the 7-Residue Fragment and the Full-length Aβ-42 Peptide.

Our recent molecular dynamics simulations of decomposing Alzheimer's disease plaques, under oscillating- and static external electric fields (Os-EEFs and St-EEFs), revealed the superiority of Os-EEF for decomposing plaques consisting of the 7-residue peptide segment. This conclusion is now reinforced by studying the dimers of the short peptides and trimers of the full-length Aβ-42 peptide. Thus, the dispersed peptides obtained following St-EEF applications reformed the plaques once the St-EEF subsided.

Structure-Stability Relationships in Pt-Alloy Nanoparticles Using Identical-Location Four-Dimensional Scanning Transmission Electron Microscopy and Unsupervised Machine Learning.

Nanoparticulate electrocatalysts for the oxygen reduction reaction are structurally diverse materials. Scanning transmission electron microscopy (STEM) has long been the go-to tool to obtain high-quality information about their nanoscale structure. More recently, its four-dimensional modality has emerged as a tool for a comprehensive crystal structure analysis using large data sets of diffraction patterns.

Interpretable Machine Learning Models Delivering a New Perspective for the Reaction Mechanism between Organic Pollutants and Oxidative Radicals.

Machine learning (ML) is expected to bring new insights into the impact of organic structures on the reaction mechanisms in reactive oxygen species oxidation. However, understanding the underlying chemical mechanisms still faces challenges due to the limited interpretability of the ML models. In this study, interpretable ML models were established to predict the second-order rate constants between hydroxyl radicals (OH) and organics ().

Discovery of Potent Dengue Virus NS2B-NS3 Protease Inhibitors Among Glycyrrhizic Acid Conjugates with Amino Acids and Dipeptides Esters.

This study investigated a library of known and novel glycyrrhizic acid (GL) conjugates with amino acids and dipeptide esters, as inhibitors of the DENV NS2B-NS3 protease. We utilized docking algorithms to evaluate the interactions of these GL derivatives with key residues (His51, Asp75, Ser135, and Gly153) within 10 Å of the DENV-2 NS2B-NS3 protease binding pocket (PDB ID: 2FOM). It was found that compounds and exhibited unique binding patterns, forming hydrogen bonds with Asp75, Tyr150, and Gly153.

A New Heteroleptic Zn(II) Complex with Schiff Bases Sensitizes Triple-Negative Breast Cancer Cells to Doxorubicin and Paclitaxel.

: Triple-negative breast cancer (TNBC) is the most challenging molecular subtype of breast cancer (BC) in clinical practice, associated with a worse prognosis due to limited treatment strategies and its insensitivity to conventional drugs. Zinc is an important trace element for homeostasis, and its Schiff base metal complexes have shown promise in treating advanced tumors. In this study, four new heteroleptic Zn(II) complexes (-) with Schiff bases were synthesized, characterized, and evaluated for their activity in BC cells.

Effects of Different Weak Small Organic Acids on Clofazimine Solubility in Aqueous Media.

Background/objectives: Clofazimine (CFZ) is a Biopharmaceutics Classification System (BCS) II drug introduced in the US market in 1986 for the treatment of leprosy. However, CFZ was later withdrawn from the market due to its extremely low aqueous solubility and low absorption. In the literature, the intrinsic solubility of CFZ has been estimated to be <0.

Organic Moiety on Sn(IV) Does Matter for In Vitro Mode of Action: BuSn(IV) Compounds with Carboxylato -Functionalized 2-Quinolones Induce Anoikis-like Cell Death in A375 Cells.

New tributyltin(IV) complexes containing the carboxylate ligands 3-(4-methyl-2-oxoquinolin-1(2H)-yl)propanoic acid () and 2-(4-methyl-2-oxoquinolin-1(2H)-yl)acetic acid () have been synthesized. Their structures have been determined by elemental microanalysis, FT-IR and multinuclear NMR (H, C and Sn) spectroscopy and X-ray diffraction study. A solution state NMR analysis reveals a four-coordinated tributyltin(IV) complex in non-polar solvents, while an X-Ray crystallographic analysis confirms a five-coordinated trigonal-bipyramidal geometry around the tin atom due to the formation of 1D chains.

A Novel Polytetrahydrofuran-Based Shape Memory Polyurethane Enhanced by Polyglycolide-Block-Polytetrahydrofuran-Block-Polyglycolide Copolymer.

A series of polyurethanes (PU-GT) were prepared using polyglycolide-block-polytetrahydrofuran-block-polyglycolide (PGA-PTHF-PGA), polytetrahydrofuran homopolymer (PTHF), glycerol, and hexamethylene diisocyanate (HDI) by a one-pot synthesis method. The non-isothermal crystallization and subsequent heating curves showed that the PTHF component in these polyurethanes could crystallize in a temperature range of -11.5~2.

Magnetic Composite Carbon from Microcrystalline Cellulose to Tackle Paracetamol Contamination: Kinetics, Mass Transfer, Equilibrium, and Thermodynamic Studies.

This study reported a one-spot preparation of magnetic composite carbon (MCC@Fe) from microcrystalline cellulose (MC). The pure cellulose was impregnated in iron (III) chloride solution and carbonized at 650 °C. The MCC@Fe composite adsorbent underwent various characterization techniques.

Closing Editorial: Research Progress on Chitosan Applications.

Chitosan has attracted significant attention due to its versatile properties, which make it an ideal candidate for varied biomedical and industrial applications [...

Anionic Oligo(ethylene glycol)-Based Molecular Brushes: Thermo- and pH-Responsive Properties.

Anionic thermo- and pH-responsive copolymers were synthesized by photoiniferter reversible addition-fragmentation chain transfer polymerization (PI-RAFT). The thermo-responsive properties were provided by oligo(ethylene glycol)-based macromonomer units containing hydrophilic and hydrophobic moieties. The pH-responsive properties were enabled by the addition of 5-20 mol% of strong (2-acrylamido-2-methylpropanesulfonic) and weak (methacrylic) acids.

Effect of Herbicide-Resistant Oil-Degrading Bacteria on Plants in Soil Contaminated with Oil and Herbicides.

Biological remediation of agricultural soils contaminated with oil is complicated by the presence of residual amounts of chemical plant protection products, in particular, herbicides, which, like oil, negatively affect the soil microbiome and plants. In this work, we studied five strains of bacteria of the genera and , which exhibited a high degree of oil biodegradation (72-96%). All strains showed resistance to herbicides based on 2,4-D, imazethapyr and tribenuron-methyl, the ability to fix nitrogen, phosphate mobilization, and production of indole-3-acetic acid.

Status of Inappropriate Complementary Feeding and Its Associated Factors Among Infants of 9-23 Months.

Inappropriate complementary feeding during the first two years of life significantly impacts children's health, increasing risks of malnutrition and illness. : This study investigates factors influencing early feeding patterns among 600 mothers of children aged 9-23 months in selected hospitals in Punjab, Pakistan. Using a structured questionnaire, data were collected and analyzed, with associations measured by odds ratios (ORs) and 95% confidence intervals (CIs).

Endophytic Fungi Co-Culture: An Alternative Source of Antimicrobial Substances.

Antimicrobial resistance is becoming a critical issue due to the widespread and indiscriminate use of antibiotics and antifungals to treat common infections, leading to a growing shortage of effective drugs. Moreover, the increase in antimicrobial resistance is enhancing the pathogenicity and virulence of various pathogens. Microorganisms are key sources of chemically diverse specialized metabolites, which are produced in the final stages of their growth cycle.

Antinociceptive Potential of L. Bark Extract and Caffeic Acid: Insights into Pain Modulation Pathways.

This study evaluated the antinociceptive effect of the L. bark extract (HEXA) and its primary component, caffeic acid (CA), through in vivo assays. : The antinociceptive properties were assessed using abdominal writhing, hot plate, and Von Frey tests.

Modulatory Effect of Cucurbitacin D from on ZNF217 Oncogene Expression in NPM-Mutated Acute Myeloid Leukemia.

The expression of oncogene zinc-finger protein 217 (ZNF217) has been reported to play a central role in cancer development, resistance, and recurrence. Therefore, targeting ZNF217 has been proposed as a possible strategy to fight cancer, and there has been much research on compounds that can target ZNF217. The present work investigates the chemo-preventive properties of cucurbitacin D, a compound with a broad range of anticancer effects, in hematological cancer cells, specifically with regard to its ability to modulate ZNF217 expression.

Important Aspects of the Design of Experiments and Data Treatment in the Analytical Quality by Design Framework for Chromatographic Method Development.

In the analytical quality by design (AQbD) framework, the design of experiments (DOE) plays a very important role, as it provides information about how experimental input variables influence critical method attributes. Based on the information obtained from the DOE, mathematical models are generated and used to build the method operable design region (MODR), which is a robust region of operability. Data treatment steps are usually carried out in software such as Fusion QbD, Minitab, or StaEase 360, among others.

Chemical Modification of Acrylonitrile-Divinylbenzene Polymer Supports with Aminophosphonate Groups and Their Antibacterial Activity Testing.

Bacterial contamination is a major public health concern on a global scale. Treatment resistance in bacterial infections is becoming a significant problem that requires solutions. We were interested in obtaining new polymeric functionalized compounds with antibacterial properties.

α-Tocopherol and Trolox as Effective Natural Additives for Polyurethane Foams: A DFT and Experimental Study.

In this work, α-tocopherol and trolox were studied as compounds that have high biological activity. α-Tocopherol is considered a food additive because the refining process of vegetable oils causes the depletion of this vitamin, and thus, its inclusion is required to keep them from oxidizing. Computational tools have determined the antioxidant activity of these additives.

Reaction of Lactone-Containing Poly(benzofuran--arylacetic acid) with Diamines to Cross-Linked Products of Improved Thermal Conductivity.

The recently developed phenoplast-related polymer, poly(benzofuran--arylacetic acid), presents a versatile molecular structure containing lactone and carboxylic acid functionalities that offer significant flexibility in creating cured materials with tailored properties for diverse applications, wherein also the thermal conductivity is an important factor. This study analyses the possibility of forming amide moieties of poly(benzofuran--arylacetic acid) with diamines resulting in cross-linked products in order to control its thermal properties. The cross-linking process is achieved by utilizing three distinct diamines, 1,6-diaminohexane, -xylylenediamine, and 4,7,10-trioxa-1,13-tridecanediamine, each possessing different degrees of polarity, flexibility, and reactivity.

Regioselective Nucleophilic Aromatic Substitution: Theoretical and Experimental Insights into 4-Aminoquinazoline Synthesis as a Privileged Structure in Medicinal Chemistry.

The 4-aminoquinazoline scaffold is a privileged structure in medicinal chemistry. Regioselective nucleophilic aromatic substitution (SAr) for replacing the chlorine atom at the 4-position of 2,4-dichloroquinazoline precursors is well documented in the scientific literature and has proven useful in synthesizing 2-chloro-4-aminoquinazolines and/or 2,4-diaminoquinazolines for various therapeutic applications. While numerous reports describe reaction conditions involving different nucleophiles, solvents, temperatures, and reaction times, discussions on the regioselectivity of the SAr step remain scarce.

Novel Copper(II) Coordination Compounds Containing Pyridine Derivatives of -Methoxyphenyl-Thiosemicarbazones with Selective Anticancer Activity.

Ten coordination compounds, [Cu(L)Cl] (), [Cu(L)NO] (), [Cu(L)Cl] (C3), [Cu(L)NO] (), [Cu(L)Cl] (), [Cu(L)NO] (), [Cu(L)NO] (), [Cu(L)Cl] (), [Cu(L)Cl] (), and [Cu(L)NO] (), containing pyridine derivatives of -methoxyphenyl-thiosemicarbazones were synthesized and characterized. The molecular structure of four compounds was investigated using single crystal X-ray diffraction. Spectral analysis techniques such as FT-IR, H NMR, C NMR, elemental analysis, and molar conductivity were used for all the synthesized compounds.