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New graphene-nickel gallate nanocomplex (G-M-Ni) was designed, synthesized and characterized to deal with the requirement of functional combustion catalyst based on investigations of combustion mechanisms of propellant, structural analysis of catalyst and simulation results of quantum mechanics. The positive effect of G-M-Ni is not only reflected in the significantly increased burning rate, but also reflected in the reduction of friction sensitivity of composite modified double base (CMDB) propellant. The G-M-Ni nanocomplex exhibited significantly enhanced catalytic performances, and the burning rate of propellant at 20 MPa enhanced from 23.15 to 29.07 mm·s−1. Besides, the friction sensitivity of propellant reduced from 64 % to 36 % after addition of 0.5% G-M-Ni. The positive effect of G-M-Ni on CMDB propellant combustion is mainly attributed to its promotion impact on nitroglycerin (NG) pyrolysis, which significantly increased the differential charge density and decreased the decomposition activation energy (from 1.89 eV to 1.38 eV). The gas products produced by the rapid pyrolysis of NG are conducive to the heat feedback between the gas phase and the combustion surface, which makes the propellant have higher burning rate, bright flame, thin dark zone and flocculated quenching surface morphology. The findings in this study confirm the potential of G-M-Ni as a functional combustion catalyst for CMDB propellants, which has guiding significance and inspiration for the development of new combustion catalysts from the view of molecular-level insights. Recently, graphene based functional combustion catalysts have attracted much attention in the field of solid propellants due to their excellent catalytic combustion performance, reduced sensitivity, and improved mechanical properties. Herein, novel graphene-nickel gallate nanocomplex (G-M-Ni) were designed, synthesized and characterized to deal with the to deal with the requirement of functional combustion catalyst based on investigations of combustion mechanisms of CMDB propellant, structural analysis of new material and simulation results of quantum mechanics. By taking graphene as the benchmark, the G-M-Ni nanocomplex exhibited significantly enhanced catalytic performances, and excellent effect on the reduction of friction sensitivity. The relationship between molecular structure of G-M-Ni and combustion characteristics of CMDB propellant were disclosed. The theory-driven design mode of this work may provide new pathways to tune combustion behaviors of CMDB propellants from the view of molecular-level insights. The relationship between molecular structure of G-M-Ni and combustion characteristics of CMDB propellant were disclosed from the view of molecular-level insights. [Display omitted] • Graphene-nickel gallate nanocomplex (G-M-Ni) was first investigated in CMDB propellant. • G-M-Ni is conducive to the combustion and safety performance of CMDB propellant. • Explored the structure-activity relationship of G-M-Ni at the molecular level. • The key catalytic step of catalyst for CMDB propellant combustion was suggested. [ABSTRACT FROM AUTHOR]

Copyright of Food & Fermentation Industries is the property of Food & Fermentation Industries and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

New graphene Schiff base iron nanocomplexes (S-792-Fe, S-550-Fe, and S-590-Fe) were designed and fabricated based on investigations of reactions mechanisms of AP pyrolysis, structural analysis of new materials and simulation results of quantum mechanics to deal with the long-standing contradiction between safety and performance for composite propellent combustion catalyst. By taking traditional catalyst Catocene as the benchmark, the S-550-Fe nanocomplexes exhibited competitive catalytic performances, much better anti-migration properties and significantly reduced impact and electrostatic sensitivities. After adding S-550-Fe, the burning rate of propellant enhanced from 13.87 to 19.77 mm s−1 at 15 MPa, and the impact and electrostatic sensitivities are improved to 50.2 cm and 172.12 mJ, respectively. The excellent catalytic performance of S-550-Fe is closely related to its molecular structure, which is manifested by an increase in charge density and a decrease in NH 3 oxidation energy barriers. The promotion effects of S-550-Fe on desorption and oxidation of NH 3 from the surface of AP is conducive to the rapid and complete pyrolysis of AP, which is reflected in the improvement of combustion rate and temperature gradient. The theory-driven design mode of this work may provide new pathways to tune combustion behaviors of composite propellants from the view of molecular-level insights. Effects and mechanisms of S-550-Fe on combustion and safety of AP-HTPB propellant were disclosed. [Display omitted] • Graphen Schiff base Fe nanocomplexes were first investigated in AP-HTPB propellant. • S-550-Fe is conducive to the combustion and safety performance of AP-HTPB propellant. • The structure-activity relationship of S-550-Fe at the molecular level was explored. • The influence of catalysts on NH 3 oxidation process was revealed. [ABSTRACT FROM AUTHOR]

Solid-state near-infrared (NIR) luminescence fluorophores have attracted much attention due to their potential in bio applications and advanced optical devices. Therefore, it is essential to design and synthesize novel NIR AIE fluorophores and investigate their structure–activity relationships for applications. Here, we synthesized two NIR AIE o-carborane fluorophores with donor–acceptor–donor (D–A–D) structures. These fluorophores have emissions extending into the NIR region and are named CPO and CPS with phenoxazine (PXZ) and phenothiazine (PTZ) derivatives as the electron donors, respectively. Despite the very similar chemical structures of PXZ and PTZ, CPO and CPS exhibited rather different photophysical properties. The o-carborane fluorophores CPO and CPS show large Stokes shifts (>14 000 cm−1), near-infrared AIE characteristics, and self-recovering mechanochromic luminescence. The reorganization of the molecular structures in the excited state leads to the planarization of their conjugated backbones and enhances the Stokes shifts. This work not only demonstrates an efficient strategy for constructing organic NIR AIE o-carborane-containing fluorophores, but also indicates their promising potential as advanced optoelectronic materials. [ABSTRACT FROM AUTHOR]

AbstractTopological indices are well-known molecular descriptors that may be applied to any graph and to model specific molecular structures, utilized for property correlation in quantitative structure activity and property relationship (QSAR and QSPR) analyses. Strong methods for machine learning information and thermodynamic simulations of massive networks and nanomaterials can be facilitated by using topological indices. Kekulenes are a novel type of cycloarenes, arranged in doughnut-shaped cyclic benzene rings with riveting superaromaticity and other significant properties. The main aim of this paper is to ascertain the notable degree and the neighborhood degree sum-based indices through M-polynomials and neighborhood M-polynomials of certain types of tessellations of kekulenes. Then, a graphical comparison of the resulting indices is also performed. [ABSTRACT FROM AUTHOR]

The exploration of chemical space is a fundamental aspect of chemoinformatics, particularly when one explores a large compound data set to relate chemical structures with molecular properties. In this study, we extend our previous work on chemical space visualization at the pharmacophoric level. Instead of using conventional binary classification of affinity (active vs inactive), we introduce a refined approach that categorizes compounds into four distinct classes based on their activity levels: super active, very active, active, and inactive. This classification enriches the color scheme applied to pharmacophore space, where the color representation of a pharmacophore hypothesis is driven by the associated compounds. Using the BCR‐ABL tyrosine kinase as a case study, we identified intriguing regions corresponding to pharmacophore activity discontinuities, providing valuable insights for structure‐activity relationships analysis. [ABSTRACT FROM AUTHOR]

In recent years, the global perspective of small molecule activation has directed the focus towards biomimetic oxidations. Phenoxazinone synthase and catechol oxidase, two vital metalloenzymes, have drawn the attention of the scientific community towards their catalytic performances. Different transition metal-based complexes have been investigated to mimic their activities, yet many factors related to their mechanistic aspects and structure–activity relationship still lack detailed investigation. To get better insights into these factors, two penta-coordinated cis-dichloro and dibromo Cu(II) complexes [Cu(L)Cl2] 1 and [Cu(L)Br2] 2 (where L = N,N-dimethyl-4,6-di(pyridin-2-yl)-1,3,5-triazin-2-amine) were synthesized and comprehensively characterized through various spectroscopic and analytical tools such as UV-vis, FT-IR, NMR, EPR and ESI-MS. The redox behaviour of ligands as well as both the copper complexes were analysed. The molecular structure of 1 and 2 was elucidated via single-crystal X-ray diffraction analysis and a distorted square pyramidal geometry was determined. The halogen atoms (Cl for 1 and Br for 2) are found to be coordinated in a cis fashion for better substrate attachment. Catalytic performances towards the oxidation of o-aminophenol (OAPH) and 3,5-di-tert-butylcatechol (3,5-DTBC) were investigated using UV-vis spectrophotometry. Significant kinetic parameters towards the catalytic activities for 1 and 2 were determined. In terms of OAPH oxidation ability, both complexes were found to be quite comparable, with 2 having greater catalytic performance (Kcat = 156.7 h−1) than 1 (Kcat = 124.5 h−1). However, 2 shows remarkably superior activity for 3,5-DTBC oxidation (Kcat = 367.8 h−1, ∼4.5 times) than 1 (Kcat = 82.2 h−1). The mass spectrometric investigation provides information about the probable mechanistic path towards the oxidation of both the substrates. Iodometric titration experiments were performed to identify H2O2 formation, which proves the involvement of molecular O2 during the catalytic oxidation. Overall, this study offers a detailed investigation on the significance of structural lability and their profound catalytic activities for biomimetic applications, which may open a new direction toward future advancements. [ABSTRACT FROM AUTHOR]

A novel method for the synthesis of nine Schiff Bases from Formyl Coumarin at room temperature has been achieved. Novel p-tolylimino-2H-chromen-2-one derivatives are synthesized using a five-component reaction involving 4-methyl-7-substituted coumarin, dioxane, 4-formyl-7-substituted coumarin, and p-toluidine, and effective medium at 25 °C. Their molecular structure was confirmed through some spectroscopic techniques such as C, H-NMR, FT-IR, and mass spectrometry. A close look at the structure-activity relationship clearly shows the intrinsic antimicrobial activity associated with the structure of these compounds, which in some cases is reinforced by some substitutions and decreases. This study presents an efficient multicomponent protocol, which provides several advantages such as short reaction times, high yields, and easy working up this work. [ABSTRACT FROM AUTHOR]

In order to study the effect of substituents on the terpyridine molecular system, a series of substituted 2,2:6′,2″-terpyridines have been synthesized and fully characterized. The substitutions range from EWGs like –F to EDGs like –OMe, -NMe2, triphenylamine (TPA), heterocycles like furan and fused rings like anthracene. The –F, -OMe, and -NMe2 are connected to the terpyridine core via phenyl ring as spacer group whereas the TPA is attached via thienyl moiety. The furan and anthracene are directly appended to the terpyridine core. The synthesized terpyridines were structurally characterized with NMR and mass spectrometry. The terpyridines were then subjected to UV–Vis absorption, luminescence, and potentiometric analysis. An extension of the light harvesting window was observed for terpyridines with electron-donating groups (EDGs) as substituent. Density functional theory (DFT) based methods (B3LYP model with 6–311 G basis sets) were applied to optimize the molecular structures. The experimental absorption studies were simulated with TD-DFT based theoretical calculations (B3LYP with 6–311 G (d,p) basis set in DCM solvent using IEFPCM model) to ascertain the underlying electronic transitions. The findings were then used to define the structure-activity relationship. [ABSTRACT FROM AUTHOR]

Schiffs base 2-acetonyl-2-methyl benzothiazoline (AMBT) is prepared by the condensation of acetyl acetone with 2-aminothiophenol. The compound has been characterised by IR, 1H NMR spectra. HyperChem 7.5 software is used to study the structural features of AMBT and theoretical data so obtained is compared with experimental spectral data. Quantum mechanical calculations were done by HyperChem 7.5 software. Ab Initio method is used for geometry optimization. Quantum calculation of molecular electronic structure and variables for Quantitative structure-activity relationships (QSAR) of AMBT were determined by applying Austin Model 1, or AM1 a semi-empirical method. Computation of HOMO and LUMO frontier orbital energies is also performed. The relationship between the structure and energy gap is studied. pH-metry studies confirm that in AMBT Molecule there exists only one proton which is dissociable. [ABSTRACT FROM AUTHOR]

The molecular structures of six neutral copper(II) complexes with propylenediamine bridges and different terminal groups have been reported and evaluated. Different antioxidant tests were performed on these complexes. Additionally, the antibacterial and antifungal activities of the investigated compounds were assessed. The study was complemented with data on their interaction with human serum albumin (HSA) and evaluated using spectroscopic fluorescence techniques. The copper(II) complexes were found to bind to HSA at multiple sites (n = 0.82–1.72), displaying relatively high binding constants on the order of Ka = (4.8–8.8) × 104 M−1. Furthermore, binding constants calculated from microscale thermophoresis (MST) data were within the range of 1.27 × 104–1.13 × 105 M−1; these results correlated well with the above Ka values obtained by fluorimetry. Molecular docking simulations were employed to study the ability of the complexes to bind to target macromolecules, such as HSA and DNA. As a significant addition to understanding their biological behavior, an MTT assay was performed to investigate the cytotoxicity of the complexes. The antiproliferative activity of the investigated copper(II) complexes with propylenediamine ligands, along with cisplatin as a reference compound, was evaluated in two human cancer cell lines (LS-174 and MCF-7) and one normal cell line (MRC-5). The obtained results are discussed, providing the structure–activity relationship of the copper(II) complexes with Schiff base tetradentate ligands. [ABSTRACT FROM AUTHOR]

Background: A heterocyclic hydrocarbon with distinct fundamental structural features in its molecular structure is imidazole. In Generalized seizure, patient brain has abnormal electrical activity on both sides of the brain but in partial seizures, it happens when electrical activity surges in one part of brain. In the present work, molecular docking analysis was conducted on proposed protein derivatives from the protein data bank using the Auto Dock for Docking programme. Study on protein binding affinity using N-(2-chlorophenyl)-2-(2-methyl-5-nitro-1H-imidazol-1-yl) acetamide derivatives and the GABA receptor. Even if a number of innovative anticonvulsants have been created in India, some types of seizures are still not adequately controlled by smaller side effects even after the use of modern and revolutionary treatments. The World Health Organisation (WHO) estimates that 65 million people worldwide suffer from epilepsy. Nevertheless, epilepsy is an uncontrollable, neurological seizure. Materials and Methods: 2-cholro aniline, 2-nitro aniline, 3-nitro aniline, formic acid, acetamide, benzamide and ethanamide have been employed in this study. Results: Our research led us to the conclusion that a variety of compounds have strong anticonvulsant properties. 2-(2-methyl-5-nitro-1H-imidazol-1-yl)-N-{2-[(3-nitrophenyl)amino]phenyl} acetamide OL4;2-{[(2-methyl-5-nitro-1H-imidazol-1-yl) acetyl]amino}phenyl acetate OL5; 2-{[(2-methyl-5-nitro-1H-imidazol-1-yl)acetyl]amino}phenyl propanoate OL6; N-(2-{[(2-methyl-5-nitro-1H-imidazol-1-yl)acetyl]amino}phenyl)propanamide OL7 gives strong anti-convulsant effects against phenytoin drug. Conclusion: The title compounds and its derivatives were examined for their ability to treat convulsions. Studies of the relationship between structure and activity revealed that compounds containing imidazole derivatives that have an electron-withdrawing group have higher activity than those that have an electron-donating group. [ABSTRACT FROM AUTHOR]

The organic anion transporter 3 (OAT3), an important renal uptake transporter, is associated with drug-induced acute kidney injury (AKI). Screening and identifying potent OAT3 inhibitors with little toxicity in natural products, especially flavonoids, in reducing OAT3-mediated AKI is of great value. The five strongest OAT3 inhibitors from the 97 flavonoids markedly decreased aristolochic acid I-induced cytotoxicity and alleviated methotrexate-induced nephrotoxicity. The pharmacophore model clarified hydrogen bond acceptors and hydrophobic groups are the critical pharmacophores. These findings would provide valuable information in predicting the potential risks of flavonoid-containing food/herb-drug interactions and optimizing flavonoid structure to alleviate OAT3-related AKI. [ABSTRACT FROM AUTHOR]

With the deterioration of underground coal quality, hundreds of millions of tons of coal slime in China need to be treated using flotation methods every year. However, the design and selection of coal slurry flotation collectors lack theoretical guidance. In this paper, the quantitative structure–activity relationship (QSAR) model between the molecular structure descriptors of collectors and the flotation recovery and selectivity index is established by using pure kaolinite/clean coal flotation experiments and molecular simulation techniques. Flotation results showed that the flotation recovery rate of kaolinite by collectors with larger head group size, such as DDMAC, DDP, and DTAC, is higher than that of the other collectors with smaller head group size. DDA, DDP, and DD have similar flotation capabilities for clean coal, and their selectivity was slightly better than others. The QSAR model between the molecular structure descriptor and the selectivity index was successfully constructed by combining flotation experiments and molecular simulation results. The reliability of this model has been proven through theoretical analysis and flotation experiments. The molecular simulation results indicate that all eight collectors can advertise on 001 (−) surface of kaolinite, but the final advertisement configuration is different. DDA has less coverage on the surface of kaolinite. When the collector is DDA, the concentration of water molecules near the 001 (−) surface of kaolinite is the highest, indicating that the collector DDA has the weakest effect on improving the hydrophobicity of the 001 (−) surface of kaolinite. DDMAC and DDBAC have the best facilitation to the surface hydrophobicity of kaolinite 001 (−). The research results have theoretical guidance significance for the selection and design of mineral flotation collectors. [ABSTRACT FROM AUTHOR]

Coumarin (2H-1-benzopyran-2-one) presents the fundamental structure of an enormous class of biologically active compounds of natural, semi-synthetic, and synthetic origin. Extensive efforts are continually being put into the research and development of coumarin derivatives with medicinal properties by the broad scientific community. Transition metal coordination compounds with potential biological activity are a "hot topic" in the modern search for novel drugs. Complexation with transition metals can enhance the physiological effect of a molecule, modify its safety profile, and even imbue it with novel attributes of interest in the fields of medicine and pharmacy. The present review aims to inform the reader of the latest developments in the search for coumarin transition metal complexes with biological activity, their potential applications, and structure-activity relationships, where such can be elucidated. Each section of the present review addresses a certain kind of biological activity (antiproliferative, antioxidant, antimicrobial, etc.), explores the most recent discoveries in the field, and, at the same time, tries to offer useful perspectives for potential future investigations. [ABSTRACT FROM AUTHOR]

In this investigation, we undertook a comprehensive quantitative structure-activity relationship (QSAR) analysis using both modern artificial neural network (ANN) methods and classical multiple linear regression methods (MLR). Our primary focus was on revealing the intricate connection between antidiabetic activity and the molecular structure of thirty-nine imidazolidine-2,4-dione derivatives. The B3LYP hybrid functional and 6-31G (d) basis set computed electronic properties at the quantum level. Rigorous benchmarking against experimental data validated the reliability of our quantum theory approach. Our statistical model effectively predicted activities closely aligned with experimental antidiabetic activities, quantified by the IC50 values. They also revealed a significant superiority of the ANN architecture (6-4-1) over the MLR method. This study stands as a meaningful contribution to the field, providing valuable insights for designing new antidiabetic drugs, particularly as potential inhibitors of tyrosine phosphate 1B (PTP1B). The explicit articulation of our primary aim and emphasis on the study's significance underscore its potential impact on advancing drug development within the realm of antidiabetic therapeutics. [ABSTRACT FROM AUTHOR]

Diabetes, a metabolic disease characterized by hyperglycemia, seriously endangers the health and the lives of people. α-Amylase inhibitors have become effective substances to control blood glucose, and attracted extensive attention. In this study, a database of α-amylase inhibitors derived from naturally active small molecules in food was created and a quantitative structure-activity relationship model was developed by combining three machine learning methods (SVM, RF, and LDA) with four descriptors (MOE, ChemoPy, Mordred, and Rdkit). Hydrogen bond and hydrophobic interaction in the inhibition of α-amylase activity was confirmed by molecular docking. Enzyme inhibition experiments showed that the predicted compound had α-amylase inhibitory activity. Nevadensin was identified as a promising candidate of α-amylase inhibitors. The stability of α-amylase binding reaction was verified by molecular dynamics simulation. Optimal process conditions for the extraction of nevadensin from L. pauciflorus maxim were derived from single-factor experiments and response surface modeling. A promising method for digging natural α-amylase inhibitors was developed and the mode between inhibitors and α-amylase was explained in this research. [Display omitted] • A strategy for the development of a novel food-derived hypoglycemic compound. • QSAR utilizes molecular structure for high-throughput screening α-amylase inhibitor. • Bioinformatics facilitates the discovery of new food-derived hypoglycemic compounds. • Molecular dynamics simulations of selected compounds. • The nevadensin extraction process was optimized through the response surface model. [ABSTRACT FROM AUTHOR]

In this paper, two calculation methods, quantum mechanics and molecular dynamics, are used to simulate the polyimides with 12 different molecular structure models. First, a variety of structural parameters that may be related to the dielectric constant are screened out, including free volume fraction, solubility parameters, the most negative atomic net charge, etc. Then, a stepwise regression analysis model is constructed using the parameters and dielectric constant, preliminary identification of property parameters with significant correlation with dielectric constant, and in-depth analysis of the rationality, structure–activity relationship, correlation, and other aspects of the multiple linear regression model. The results indicate that the p-value is less than p = 0.000 < 0.05, and the design of the model has important practical value; There is an inherent relationship between the five structural parameters and the dielectric constant—solubility parameters are positively correlated with end distance/free volume and dielectric constant, while the net charge of the most negative atom, free volume fraction, length of side groups are negatively correlated with dielectric constant. In addition, increasing the free volume of polyimide is more effective than changing the polarity to reduce the dielectric constant of polyimide. [ABSTRACT FROM AUTHOR]

The article titled "Synthesis of 6-Alkylamino-2-alkylthio(alkoxy) Purine Derivatives: Antiplatelet Aggregation Activity Evaluation and 3D-QSAR Analysis" explores the relationship between the structure of purine derivatives and their ability to prevent platelet aggregation. The researchers synthesized 46 purine derivatives and tested their antiplatelet aggregation activity. They found that modifying the substituents on the purine ring could lead to more effective antiplatelet drugs. The study also includes a 3D-QSAR analysis to analyze the structural factors contributing to the activity. The findings provide valuable insights into the potential of these compounds as antiplatelet agents. [Extracted from the article]

BACKGROUND: Diabetes mellitus poses a substantial threat to public health due to rising morbidity and mortality. α‐Glucosidase is one of the key enzymes affecting diabetes. Herein, (−)‐epigallocatechin‐3‐gallate (EGCG) and (−)‐epigallocatechin (EGC) were applied to clarify the role of the galloyl moiety of tea polyphenols in the inhibition of glycation and α‐glucosidase activity. The structure–activity relationship of the galloyl moiety in EGCG on α‐glucosidase was investigated in terms of inhibition kinetics, spectroscopy, atomic force microscopy and molecular docking. A bovine serum protein–fructose model was employed to determine the effect of the galloyl moiety on glycation. RESULTS: The results indicated that the introduction of a galloyl moiety enhanced the capacity of EGCG to inhibit glycation and α‐glucosidase activity. The IC50 value of EGC is approximately 2400 times higher than that of EGCG. Furthermore, the galloyl moiety in EGCG altered the microenvironment and secondary structure of α‐glucosidase, resulting in a high binding affinity of EGCG to α‐glucosidase. The binding constant of EGCG to α‐glucosidase at 298 K is approximately 28 times higher than that of EGC. CONCLUSION: Overall, the galloyl moiety of EGCG plays a crucial role in inhibiting glycation and α‐glucosidase activity, which helps to enhance the molecular understanding of the structure and function of the polyphenol galloyl moiety in the science of food and agriculture. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Copyright of Petroleum Geology & Oilfield Development in Daqing is the property of Editorial Department of Petroleum Geology & Oilfield Development in Daqing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Enaminonitrile pyridine derivative was used as a precursor for preparation of fourteen heterocyclic compounds using both conventional thermal and microwave techniques. Diverse organic reagents, such as chloroacetyl chloride, acetic anhydride, chloroacetic acid, carbon disulfide, p-toluene sulfonyl chloride, maleic anhydride, phthalic anhydride, were used. The chemical formulae and structures of isolated derivatives were obtained using different analytical and spectroscopic techniques such as IR, 1H-, 13C-NMR as well as mass spectrometry. The spectroscopic analyses revealed diverse structure arrangements for the products. Molecular structure optimization of certain compounds were performed by the density functional theory (DFT/B3LYP) method and the basis set 6–31 G with double zeta plus polarization (d,p). The antimicrobial inhibition and the antioxidant activity of the reported compounds were screened. Compounds 5, 6, 11 and 13 exhibited the highest antibacterial inhibition, while compound 8 gave the highest scavenging activity (IC50 43.39 µg/ml) against the DPPH radical. Structure–activity relationship of the reported compounds were correlated with the data of antibacterial and the antioxidant activity. The global reactivity descriptors were also correlated with the biological properties of compounds. The molecular docking studies of reported compounds were investigated, and the analysis showed that the docked compounds have highly negative values for the functional binding scores. The binding interaction was found to be correlated with the substituent fragments of the compounds. [ABSTRACT FROM AUTHOR]

Carbon hydrocarbon compounds, especially low-carbon hydrocarbons (C1–C3), are vital raw materials in the petrochemical industry, but their efficient separation has great challenges due to their similar molecular structures and properties. In contrast to traditional low-temperature distillation and absorption separation technologies, selective adsorption employing porous materials as adsorbent has the advantages of low energy consumption, high efficiency, and high selectivity, indicating broad application possibilities in the field of low-carbon hydrocarbon separation. In this paper, the recent progress in the separation and purification of hydrocarbon mixtures by means of the two kinds of porous materials (metal–organic frameworks and molecular sieves) that have been widely used in recent years is reviewed, including purification of methane and separation of ethylene/ethane, propylene/propane, and some high-carbon hydrocarbon isomers. The structure–activity relationships between their chemical composition, structural characteristics, and separation performance are discussed to understand the separation mechanism. In conclusion, the issues encountered in the application of metal–organic frameworks and molecular sieves in the separation of low-carbon hydrocarbons are discussed in light of the current context of "carbon neutrality". [ABSTRACT FROM AUTHOR]

Catechols have important applications in the pharmaceutical, food, cosmetic, and functional material industries. 4-hydroxyphenylacetate-3-hydroxylase (4HPA3H), a two-component enzyme system comprising HpaB (monooxygenase) and HpaC (FAD oxidoreductase), demonstrates significant potential for catechol production because it can be easily expressed, is highly active, and exhibits ortho-hydroxylation activity toward a broad spectrum of phenol substrates. HpaB determines the ortho-hydroxylation efficiency and substrate spectrum of the enzyme; therefore, studying its structure–activity relationship, improving its properties, and developing a robust HpaB-conducting system are of significance and value; indeed, considerable efforts have been made in these areas in recent decades. Here, we review the classification, molecular structure, catalytic mechanism, primary efforts in protein engineering, and industrial applications of HpaB in catechol synthesis. Current trends in the further investigation of HpaB are also discussed. [ABSTRACT FROM AUTHOR]

Among the numerous heterocyclic families, pyrazoles and pyrazolones are among the most interesting, in part due to their demonstrated biological activities.[[1], [3]] Pyrazolones are well-known as analgesics,[4] anti-oxidants,[5] protein kinase inhibitors,[6] antihyperlipidemics,[7] anticonvulsants,[8] antidepressants,[9] antifungals,[10],[11] antivirals,[12] antidiabetics,[13] anti-inflammatories,[14] antibacterials,[15] anticancer drugs,[16],[17] and antitubercular medications.[18] Some currently-marketed pyrazolones, such as propyphenazone, ampyrone and metamizole, are antipyretics and analgesics.[19] For their part, the more structurally-complex arylidenepyrazolones also have analgesic,[20] anti-inflammatory,[20],[21] antimicrobial,[21] anti-oxidant,[22] and antitubercular activities.[23] Some representative arylidenepyrazolones are shown in Figure 1. 4-(4-Hydroxybenzylidene)-3-methyl-1-phenyl-1H-pyrazol-5(4H)-one (3d) SP 1 sp H NMR (250 MHz, DMSO-d SB 6 sb ): 10.91 (s, 1H, OH), 8.66 (d, J = 8.7 Hz, 2H, Ar-H), 7.92 (d, J = 8.6 Hz, 2H, Ar-H), 7.68 (s, 1H, H-Csp SP 2 sp ), 7.46-7.40 (m, 2H, Ar-H), 7.12-7.21 (m, 1H, Ar-H), 6.97 (d, J = 8.7 Hz, 2H, Ar-H), 2.31 (s, 3H, CH SB 3 sb ). 4-(2,4-Dimethylbenzylidene)-3-methyl-1-phenyl-1H-pyrazol-5(4H)-one (3a) SP 1 sp H NMR (250 MHz, DMSO-d SB 6 sb ): 8.69-8.63 (m, 1H, Ar-H), 7.95-7.80 (m, 2H, Ar-H), 7.30 (s, 1H, H-Csp SP 2 sp ), 7.41 (t, J = 8 Hz, 2H, Ar-H), 7.12-7.21 (m, 1H, Ar-H), 6.85 (d, J = 8.0 Hz, 2H, Ar-H), 3.14 (s, 6H, 2CH SB 3 sb ), 2.28 (s, 3H, CH SB 3 sb ). 4-(4-Methoxybenzylidene)-3-methyl-1-phenyl-1H-pyrazol-5(4H)-one) (3c) SP 1 sp H NMR (250 MHz, DMSO-d SB 6 sb ): 8.54 (d, J = 8.9 Hz, 2H, Ar-H), 7.89 (d, J = 8.2 Hz, 2H, Ar-H), 7.34 (s, 1H, H-Csp SP 2 sp ), 7.32 (d, J = 8.1 Hz, 2H, Ar- H), 7.10 (t, J = 14.8 Hz, 1H, Ar-H), 6.94 (d, J = 8.8 Hz, 2H, Ar-H), 3.84 (s, 3H, OCH SB 3 sb ), 2.24 (s, 3H, CH SB 3 sb ). [Extracted from the article]

A simple, mild and efficient method was proposed to construct fused tricyclic skeletons based on Mannich reaction. This work not only develops a new method to construct the tricyclic skeletons effectively, but also provides a new insight into the fused tricyclic skeletons containing flexible ring, which will greatly contribute to the research and development of the tricyclic energetic compounds. The relationship of structure-activity was studied by weak interactions calculation, single crystal structures analysis, electrostatic potentials calculation. The experimental and theoretical investigations suggest that the fused tricyclic skeleton containing flexible ring possesses better thermal stability and can be derivatized more easily compared with the similar aromatic fused tricyclic skeleton. Besides, the energetic derivates based on the fused tricyclic skeleton containing flexible ring possess good comprehensive properties: 2 (D = 7726 m s-1, p = 22.7 GPa) and 4 (D = 8151 m s-1, p = 26.3 GPa). All these results suggest that the fused tricyclic skeleton containing flexible ring is an ideal candidate to construct energetic compounds. [ABSTRACT FROM AUTHOR]

Chemists have been pursuing general mathematical laws to explain and predict molecular properties for a long time. However, most of the traditional quantitative structure‐activity relationship (QSAR) models have limited application domains; for example, they tend to have poor generalization performance when applied to molecules with parent structures different from those of the trained molecules. This paper attempts to develop a new QSAR method that is theoretically possible to predict various properties of molecules with diverse structures. The proposed deep electron cloud‐activity relationships (DECAR) and deep field‐activity relationships (DFAR) methods consist of three essentials: (1) a large number of molecule entities with activity data as training objects and responses; (2) three‐dimensional electron cloud density (ECD) or related field data by the accurate density functional theory methods as input descriptors; and (3) a deep learning model that is sufficiently flexible and powerful to learn the large data described above. DECAR and DFAR are used to distinguish 977 sweet and 1965 non‐sweet molecules (with 6‐fold data augmentation), and the classification performance is demonstrated to be significantly better than the traditional least squares support vector machine (LS‐SVM) models using traditional descriptors. DECAR and DFAR would provide a possible way to establish a widely applicable, cumulative, and shareable artificial intelligence‐driven QSAR system. They are likely to promote the development of an interactive platform to collect and share the accurate ECD and field data of millions of molecules with annotated activities. With enough input data, we envision the appearance of several deep networks trained for various molecular activities. Finally, we could anticipate a single DECAR or DFAR network to learn and infer various properties of interest for chemical molecules, which will become an open and shared learning and inference tool for chemists. Deep electron cloud‐activity relationships (DECAR) and deep field‐activity relationships (DFAR) methods are quantitative structure‐activity relationship (QSAR) models that involve deep learning of thousands (or hundreds of thousands) of molecule entities using augmented and high‐quality 3D electron cloud or related field data as molecular structure descriptors. [ABSTRACT FROM AUTHOR]

Context: SF6 is widely used in electrical equipment due to its chemical stability and insulation strength, but it is a strong greenhouse gas and its use has been restricted internationally. In order to reduce the SF6 usage, it is needed to find a replacement gas for SF6. Electrical breakdown test is always adopted to select potential substitutes, but it is resource and time intensive. Thus, a structure-activity relationship model is needed to effectively predict the gas insulation strength. In this work, we calculated the isosurface electrostatic potential of 68 gas molecules in case of electron probability density, Laplacian of electron density, electron localization function, and localized orbital function. The distribution characteristics of these four real space functions were analyzed. Furthermore, correlation between the electrostatic potential parameters and insulation strength was presented. Finally, a prediction model for insulation strength of gaseous medium was established. Using the electrostatic potential parameter on the localized orbital locator function with a threshold of 0.05 a.u., the prediction model achieved the best performance with a coefficient of determination of 0.860 and a mean squared error of 0.0663. Methods: The quantization calculation tool used in this work is the GAUSSIAN 16 software. The M06-2X method with the 6-311G++(d, p) basis set is used to optimize the molecular structure and output stable wavefunction files. Then the wavefunction analysis software Multiwfn is used to plot the contour map of the gas molecules and calculate the radial distribution patterns. [ABSTRACT FROM AUTHOR]

Electrochemical oxidation is an efficient method for the destruction of dyes in wastewater streams. The experimental conditions during electrochemical oxidation (EO) and molecular structure of a dye greatly influence the extent of degradation. The extent of degradation for a variety of dyes by EO can be predicted conveniently by the use of Quantitative structure–activity Relationship (QSAR) models. An abundant amount of published data on dye degradation by EO using highly variable experimental conditions lies unutilized to prepare QSAR models. In this study, an effort is made to use published experimental data on EO of aqueous dyes after applying an easy method of normalization, to prepare QSAR models for percent color and COD removal. Normalized color and COD removal were obtained by multiplying the reported removal by volume of reactor and concentration of dye; and divided by total current passed and the time of electrolysis. More than 15 molecular descriptors were computed using Schrodinger-suit 2018-3. The multiple linear regression (MLR) approach was used to develop normalized color and COD removal models. The quantum chemical descriptors: highest occupied molecular orbital energy (HOMO) and lowest unoccupied molecular orbital energy (LUMO), polar surface area (PSA), hydrogen bond donor count (HBD), and number of atoms were found significant. The statistical indices: goodness-of-fit, R2 > 0.75, and internal and external validations, Q2LOOCV and Q2ext, > 0.5, satisfied the criteria for predictive models and indicated that the method of normalization used in this study is adequate. Developed QSAR models are quite simple, interpretable, and transparent. [ABSTRACT FROM AUTHOR]

Leishmaniasis, a parasitic disease that represents a threat to the life of millions of people around the globe, is currently lacking effective treatments. We have previously reported on the antileishmanial activity of a series of synthetic 2-phenyl-2,3-dihydrobenzofurans and some qualitative structure–activity relationships within this set of neolignan analogues. Therefore, in the present study, various quantitative structure–activity relationship (QSAR) models were created to explain and predict the antileishmanial activity of these compounds. Comparing the performance of QSAR models based on molecular descriptors and multiple linear regression, random forest, and support vector regression with models based on 3D molecular structures and their interaction fields (MIFs) with partial least squares regression, it turned out that the latter (i.e., 3D-QSAR models) were clearly superior to the former. MIF analysis for the best-performing and statistically most robust 3D-QSAR model revealed the most important structural features required for antileishmanial activity. Thus, this model can guide decision-making during further development by predicting the activity of potentially new leishmanicidal dihydrobenzofurans before synthesis. [ABSTRACT FROM AUTHOR]

The molecular topology and the chemical structures which are not regular perform a dominant character in designing the compound in connection with their physical and chemical properties. The study of topological descriptors of molecular structures is widely used in the field of cheminformatics, information technology, biomedical science, and many more. Numerous topological indices have been evolved in the theory of chemistry. Graphs which are not regular can be specified using irregular measures. In this article, we find some irregularity indices, which are useful in Quantitative structure activity relationship for benzenoid structures. Based on the exact analytic expressions, the numerical and graphical comparison for benzenoid structures is also provided. [ABSTRACT FROM AUTHOR]

The colony‐stimulating factor 1 receptor (CSF1R) is a protein kinase emerging as an attractive target with clinical relevance in cancer, CNS and inflammatory diseases. Molecular docking experiments followed by synthesis and structure–activity relationship have been used to identify low molecular weight structures as promising hits for lead optimization. These molecules are synthesized from a 4‐chloro‐6‐iodo‐pyrrolo[2,3‐d]pyrimidine building block using Negishi and Suzuki–Miyaura cross‐coupling reactions in high yields. Several inhibitors possessed excellent enzymatic potency, and the parent compound preferably binds to the autoinhibited form of CSF1R. Cellular and in vivo profiling indicate that further tuning of drug structure is needed prior to efficacy studies. [ABSTRACT FROM AUTHOR]

Quantitative structure activity relationships (QSAR) studies, as one of the most important areas in chemometrics, play a fundamental role in predicting the biological activity of new compounds and identifying ligand-receptor interactions. Quantitative relationships between molecular structure and methionine aminopeptidase-2 inhibitory activity of a series of anthranilic acid sulfonamides derivatives were discovered by different chemometrics tools including factor analysis based multiple linear regressions (FA-MLR), principale component regression analysis (PCRA) and genetic algorithm-partial least squares GA-PLS. The FA-MLR describes the effect of geometrical and quantum indices on enzyme inhibition activity of the studied molecules. The quality of PCRA equation is better than those derived from FA-MLR. GA-PLS analysis indicated that the topological (IC4 and MPC06), constitutional (nf) and geometrical (G (N..S)) parameters were the most significant parameters on methionine aminopeptidase-2 inhibitory activity. A comparison between the different statistical methods employed revealed that GA-PLS represented superior results and it could explain and predict 85% and 77% of variances in the pIC50 data, respectively. [ABSTRACT FROM AUTHOR]

A series of ferrocene‐hydrazone based Ru(II)‐p‐cymene complexes were investigated for their catalytic activity towards acceptorless dehydrogenative coupling (ADC) reactions. Ru(II)‐p‐cymene isonicotinic Fc‐hyrazone complex performed better in the solvent‐free synthesis of 1,2‐disubstituted benzimidazoles (up to 88%) and quinazolinones (up to 95%). The catalysis was extended to a wide range of benzylic alcohols. The synthesis of 1,2‐disubstituted benzimidazoles was accomplished with electron‐donating/‐withdrawing o‐phenylenediamines as well. A catalytic structure‐activity relationship was established by varying the steric and electronic parameters on the substrates. All the catalytic experiments exhibited good to moderate yields, with hydrogen and water as the only by‐products. The prepared complexes were well characterized using analytical and spectroscopic techniques. The molecular structures of the ligands and complex were resolved using single crystal X‐ray crystallographic studies. [ABSTRACT FROM AUTHOR]

Human immunodeficiency virus type 1 (HIV-1) capsid protein (CA) plays essential roles in both early and late stages of HIV-1 replication and it is an important target for developing new therapeutic drugs. In the present study, quantitative structure–activity relationships (QSARs) models were developed for a series of 46 derivatives of PF74 CA inhibitors binding to the HIV1 capsid. The Partial least square (PLS) method was applied to obtain QSAR models based on simplex representation of molecular structure (SiRMS). Molecular docking studies were performed to find the optimal conformation of molecules within the binding site, and to compute 3D SiRMS descriptors. The study produced several statistically significant and acceptable QSAR models (R2 = 0.98, Q2 = 0.76–0.78, R2 predict = 0.84). A consensus model developed from the five excellent PLS QSAR models which was statistically validated for its predictive power using cross-validation, Y-randomization, and applicability domain evaluation procedures. The obtained results have satisfactory statistical parameters within acceptable range. The model interpreted by a reverse analysis identified the molecular fragments that promote and interfere with antiviral activity and the degree to which they influence activity. The influence of the physical–chemical properties of the molecules on antiviral activity was determined. It has been observed that antiviral activity is mainly governed by electrostatic characteristics of molecular structure and hydrophobic factors. The results obtained may further assist in the design of new CA inhibitor compounds and prediction of their activity. [ABSTRACT FROM AUTHOR]

Regulatory measures and public concerns regarding bisphenol A (BPA) have led to its replacement by structural analogues, such as BPAF, BPAP, BPB, BPF, BPP, BPS, and BPZ. However, these alternatives are under surveillance for potential endocrine disruption, particularly during the critical period of fetal development. Despite their structural analogies, these BPs differ greatly in their placental transport efficiency. For predicting the fetal exposure of this important class of emerging contaminants, quantitative structure-activity relationship (QSAR) studies were developed to model and predict the placental clearance indices (CI). The most usual input parameters were molecular descriptors obtained by modelling, but for bisphenols (BPs) with structural similarities or heteroatoms such as sulfur, these descriptors do not contrast greatly. This study evaluated and compared the capacity of QSAR models based either on molecular or chromatographic descriptors or a combination of both to predict the placental passage of BPs. These chromatographic descriptors include both the retention mechanism and the peak shape on columns that reflect specific molecular interactions between solute and stationary and mobile phases and are characteristic of the molecular structure of BPs. The chromatographic peak shape such as the asymmetry and tailing factors had more influence on predicting the placental passage than the usual retention parameters. Furthermore, the QSAR model, having the best prediction capacity, was obtained with the chromatographic descriptors alone and met the criteria of internal and cross validation. These QSAR models are crucial for predicting the fetal exposure of this important class of emerging contaminants. [ABSTRACT FROM AUTHOR]

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In 2022, the U.S. Food and Drug Administration approved a total of 16 marketing applications for small molecule drugs, which not only provided dominant scaffolds but also introduced novel mechanisms of action and clinical indications. The successful cases provide valuable information for optimizing efficacy and enhancing pharmacokinetic properties through strategies like macrocyclization, bioequivalent group utilization, prodrug synthesis, and conformation restriction. Therefore, gaining an in-depth understanding of the design principles and strategies underlying these drugs will greatly facilitate the development of new therapeutic agents. This review focuses on the research and development process of these newly approved small molecule drugs including drug design, structural modification, and improvement of pharmacokinetic properties to inspire future research in this field. [Display omitted] • The clinical applications and mechanisms of action of newly approved drugs were summarized. • The development processes and design concepts of new drugs were reviewed. • The X-ray crystal structures and molecular binding models of new drugs were exhibited. • The practical structure-activity relationship of each new drugs was summarized. [ABSTRACT FROM AUTHOR]

[Display omitted] • Three nitrogen-rich sulfur-containing adsorbents were firstly prepared. • The three adsorbents have excellent adsorption uptake, selectivity and recycling. • Increasing the N content could increase the adsorption performance. • The spatial structure also has a significant impact on the adsorption performance. • The adsorption mechanism involves electrostatic effect, coordination, and redox. Recovering precious metals from secondary resources has elicited considerable attention, and exploring an efficient adsorbent is a challenge. In this work, we have specifically tailored three highly effective adsorbents (THDA@PEI, DCTA@PEI and DCTD@PEI) by crosslinking PEI with sulfur-containing heterocyclic cross-linking agents (2,5-thiophenedicarboxaldehyde, 2,4-dichlorothiazole and 3,4-dichloro-1,2,5-thiadiazole) for recovery of Au(III), Pd(II), and Pt(IV). These agents are distinguished by a range of nitrogen atom counts that extend from zero to two, offering a foundation for exploring the correlation between their molecular structure and adsorption performance. THDA@PEI, DCTA@PEI, and DCTD@PEI exhibit remarkable adsorption capacities for Au(III), Pd(II), and Pt(IV), with values reaching up to 2169, 2240, and 2536 mg/g for Au(III), 771, 886, and 846 mg/g for Pd(II), and 832, 1021, and 887 mg/g for Pt(IV), respectively. Among the three materials, DCTD@PEI stands out with a broader pH applicability range for both gold (pH 2 to 9) and platinum (pH 1 to 11) adsorption and exhibits a more rapid adsorption rate for Au and Pd. The adsorption processes of the three adsorbents on precious metals are spontaneous and entropy-increasing processes. Increasing the adsorption temperature could improve the adsorption performance of the three adsorbents, except for Pd adsorption by DCTD@PEI. All of the three adsorbents exhibit good selectivity and reusability for Au, Pd, and Pt, with DCTA@PEI being the most outstanding. It is observed that an increase in nitrogen content in the adsorbents correlates positively with the improvement of key performance indicators, including a wider pH range, higher adsorption capacity, faster kinetics, better selectivity, and enhanced reusability, while the substituent positions of crosslinking agents also have a strong impact on the adsorption performance, especially for Pd and Pt. [ABSTRACT FROM AUTHOR]

New-energy industry produce large amount of emerging high-speed battery jarosite slag, containing Mn and Ni, which is large in quantity and harmful. Harmless treatment is in urgent need. We research on the curing mechanism of heavy metals migration and transformation during phase via iron clusters transformation in glass-ceramics. Based on first-principles and density functional theory, regulating electronic structure of Mn2+ and Ni2+ by Cr3+. After clarifying the interaction among curing compatibility, capacity and stability, the structure-activity relationship among electronic & molecular structure and leaching concentration of heavy metals was established. The results show that CaNiSi 2 O 6 is difficult to cure Ni2+, the formation of iron clusters promotes the conversion of multiphase to Fe-Spinel A; Mn2+, Ni2+ went into the octahedron in Fe-Spinel A cannot be stabilized; Cr3+ promotes migration of Mn2+, Ni2+ into the tetrahedral, turning Fe-Spinel A into Fe-Spinel B, improves curing compatibility of Mn2+, Ni2+; Cr3+ also adjust the bond structure, which enhances solid solution attraction to Mn2+ and Ni2+, and capacity of Mn2+ and Ni2+ increases from 19%, 30%–147%, 195%; improving compatibility and capacity of Fe-Spinel reduces leaching concentration of Mn2+ and Ni2+ from 1.32, 0.51 mg/L to 0.48, 0.03 mg/L. This work realizes the harmless disposal of recycling Mn- and Ni-rich battery slag. The solidified body can also be reused as eco-friendly resource. [Display omitted] • Transforming multiphase into Fe-Spinel via iron clusters, solve problems of heavy metals actively entering unstable phases. • Improving compatibility of Fe-Spinel curing Mn and Ni by adjusting the electronic structure. • Increasing curing capacity of Mn and Ni via changing bond structure. • Establishing the structure-activity relationship between electronic structure, molecular structure and curing stability. [ABSTRACT FROM AUTHOR]

Cockroaches are urban pests that are very difficult to control. Using repellents is a green, safe and effective strategy for their control. In order to find novel cockroach repellents, the repellent activity of 45 bridged-ring terpenoid derivatives synthesized from β-pinene against Blattella germanica was tested. The relationship between the molecular structure of these bridged-ring terpenoid derivatives and their repellent activity against Blattella germanica was also analysed. The results show that some of the bridged-ring terpenoid derivatives exhibit good repellent activity against Blattella germanica, and six compounds (RR = 60.44–87.32%) show higher repellent activity against Blattella germanica than DEET (RR = 54.77%), making them promising for development as new cockroach repellents. Quantitative structure–activity relationship (QSAR) analysis revealed that the HOMO-1 energy, Kier and Hall index (order 2), Balaban index, and relative positive charged surface area of bridged-ring terpenoid derivatives have effects on repellent activity against Blattella germanica. The present study may provide a theoretical basis for the high-value use of β-pinene and can be helpful to the development of novel repellents against Blattella germanica. [ABSTRACT FROM AUTHOR]

The fascinating molecular structure and versatile bioactivity of imidazo[1,2‐a]pyridine scaffold attracts the scientific community to develop new imidazo[1,2‐a]pyridine based antibacterial agent in current situation. This systematic review provides a deep insight into the recent advances of imidazo[1,2‐a]pyridine derivatives and its antibacterial activities from 2010 to 2021. Moreover, the structure–activity relationship and synthetic approaches are also cautiously summarized throughout the review which affords a clear vision for the medicinal chemists to design new antibacterial agents. [ABSTRACT FROM AUTHOR]

The electrocatalytic performance of nanomaterials can be enhanced by fine‐tuning the coordination environment and number of low‐coordination atoms. Confinement engineering is the most effective strategy for the precise chemical synthesis of electrocatalysts through the modulation of electron transfer properties, atomic arrangement, and molecular structure in a confined region. It not only alters the coordination environments to adjust the formation mechanism of active centers, but also regulates the physicochemical properties of electrocatalysts. Consequently, the nucleation, transportation, and stabilization of intermediate species in electrocatalysis are optimized, and then improve the performance covering activity, stability, and selectivity. In this review, confinement engineering is introduced in terms of confined definition, classification, construction, and basic principles. Then, the latest advances in the confinement engineering of electrocatalysts for the oxygen reduction reaction, hydrogen evolution reaction, oxygen evolution reaction, nitrogen reduction reaction, and carbon dioxide reduction reaction are systematically evaluated. Furthermore, using representative experimental results and theoretical calculations, the structure‐activity relationships between confinement engineering and electrocatalytic performance are illustrated. Finally, potential challenges and future development prospects of confined electrocatalysts are highlighted, with a focus on controlling the construction of confined environments, investigating uncommon catalytic properties in confined regions, and practical applications. [ABSTRACT FROM AUTHOR]

Malignant proliferation and metastasis are the hallmarks of cancer cells. Aminated [70]fullerene exhibits notable antineoplastic effects, promoting it a candidate for multi‐targeted cancer drugs. It is an urgent need to reveal the structure–activity relationship for antineoplastic aminated fullerenes. Herein, three amphiphilic derivatives of [60]fullerene with clarified molecular structures are synthesized: TAPC‐4, TAPC‐3, and TCPC‐4. TAPC‐4 inhibits the proliferation of diverse tumor cells via G0/G1 cell cycle arrest, reverses the epithelial–mesenchymal transition, and abrogates the high mobility of tumor cells. TAPC‐4 can be excreted from the organism and achieves an in vivo inhibition index of 75.5% in tumor proliferation and 87.5% in metastatic melanoma with a wide safety margin. Molecular dynamics simulations reveal that the amphiphilic molecular structure and the ending amino groups promote the targeting of TAPC‐4 to heat shock protein Hsp90‐beta, vimentin, and myosin heavy chain 9 (MYH9), probably resulting in the alteration of cyclin D1 translation, vimentin expression, and MYH9 location, respectively. This work initially emphasizes the dominant role of the amphiphilic structure and the terminal amino moieties in the antineoplastic effects of aminated fullerenes, providing fundamental support for their anti‐tumor drug development. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Researchers investigated the organic optoelectronic materials and facilitated their development in organic light‐emitting diodes (OLEDs), chemo‐ and biosensors, organic solar cells, data storage, and anticounterfeiting devices. Atoms make up molecules through chemical bonds, and molecular aggregates are formed through weak intermolecular interactions. The opto‐electronic performance of these materials depends on not only the properties of the well‐designed molecules with specific function groups, but also their aggregate states. The molecular aggregates in the form of nanoparticles can be applied in biological imaging, and films can be applied to photovoltaic and photodeformable devices, in which, the alignment of optoelectronic molecules can be either an ordered crystalline or an amorphous state. Generally, the crystalline materials could be deeply investigated by single crystal/powder X‐ray diffraction analysis, which could provide the accurate information about molecular conformations, interactions and packing characteristics. It afforded a convenient way to investigate the possible relationship between molecular aggregates and opto‐electronic properties. Among various opto‐electronic materials, organic room temperature phosphorescence (RTP) materials exhibit the extremely sensitive luminescence property to molecular aggregates, even the dynamic properties can be detected by the tiny change of molecular aggregates. Thus, we selected the organic RTP emission as the output information of molecular aggregates, and afforded typical examples to find the possible relation between RTP effect and molecular packing. Accordingly, molecular packing can be adjusted by the external force as light, mechanical force, temperature, electric field, and so on, as well as the molecular structures as the building blocks, and the systematic investigation in the dynamic and static aggregation structures is of great value to the design of various optoelectronic materials. This review discusses the relationship among molecular structures, aggregation behaviors and corresponding optoelectronic properties by a comprehensive summary of recent research in our group, and the concept of molecular uniting set identified characteristic (MUSIC) is afforded. What is the most favorite and original chemistry developed in your research group? The concept of "Suitable Isolation Group" for molecular design of organic second‐order nonlinear optical (NLO) materials. Molecular packing is highlighted as the key point to opto‐electronic materials, which are partially summarized in this mini review to present "MUSIC" in the molecular world. How do you supervise your students? Discussions. We do discussions for science, interests and other topics related to research together, through which to solve the encountered problems. What is the most important personality for scientific research? Curiosity, desire to advance, persistence, sense of urgency, and team spirit. What are your hobbies? What's your favorite book(s)?? Listening to music and reading books, and my favorite book is "Tao Te Ching (道德经)". Could you please give us some advices on improving Chinese Journal of Chemistry? There are many different approaches to improve CJC, perhaps, to attract and publish good papers is the key, especially those from Chinese authors since the chemistry in China develops rapidly. If you have anything else to tell our readers, please feel free to do so? While pursuing new published exciting papers, it is a very good habit to read related old excellent literatures and the classics. [ABSTRACT FROM AUTHOR]

Copper bromide complexes based on a series of substituted guanidine-quinolinyl and -pyridinyl ligands are reported. The ligand systems were chosen based on the large variation with regard to their flexibility in the backbone, different guanidine moieties and influence by electron density donating groups. Relationships between the molecular structures and spectroscopic and electronic properties are described. Beside the expected increase in activity by substituting the 4-position (NMe2vs. H), we showed that a higher flexibility, such as TMG vs. DMEG moiety, leads to a better stabilsiation of the copper(II) complex. Due to the correlation of the potentials and KATRP values, the catalyst based on the ligand TMGm4NMe2py is the most active copper complex for ATRP with a bidentate ligand system. The combination of the strong donating abilities of dimethylamine pyridinyl, the donor properties of the TMG substituent, and the improved flexibility due to the methylene bridging unit leads to high activity. With all NMe2-substituted systems standard ATRP experiments were conducted and with more active NMe2-substituted pyridinyl systems, ICAR ATRP experiments of styrene were conducted. Low dispersities and ideal molar masses have been achieved. [ABSTRACT FROM AUTHOR]

Human immunodeficiency virus (HIV) infection is a major problem for humanity because HIV is constantly changing and developing resistance to current drugs. This necessitates the development of new anti-HIV drugs that take new approaches to combat an ever-evolving virus. One of the promising alternatives to combination antiretroviral therapy (cART) is the molecular hybrid strategy, in which two or more pharmacophore units of bioactive scaffolds are combined into a single molecular structure. These hybrid structures have the potential to have higher efficacy and lower toxicity than their parent molecules. Given the potential advantages of the hybrid molecular approach, the development and synthesis of these compounds are of great importance in anti-HIV drug discovery. This review focuses on the recent development of hybrid compounds targeting integrase (IN), reverse transcriptase (RT), and protease (PR) proteins and provides a brief description of their chemical structures, structure–activity relationship, and binding mode. [ABSTRACT FROM AUTHOR]

Robust quantitative structure-activity relationships (QSARs) for hBACE-1 inhibitors (pIC50) for a large database (n = 1706) are established. New statistical criteria of the predictive potential of models are suggested and tested. These criteria are the index of ideality of correlation (IIC) and the correlation intensity index (CII). The system of self-consistent models is a new approach to validate the predictive potential of QSAR-models. The statistical quality of models obtained using the CORAL software () for the validation sets is characterized by the average determination coefficient R2v= 0.923, and RMSE = 0.345. Three new promising molecular structures which can become inhibitors hBACE-1 are suggested. [ABSTRACT FROM AUTHOR]

Lipid oxidation products can affect the molecular structure and digestibility of peanut protein isolates. Lipid‐oxidizing systems (LOS) is a simulation system which uses oxygen‐free radicals generated by the reaction of linoleic acid and lipoxygenase as oxidants.The simulation system was established to mediate oxidation of arachin or conarachin. Degree of oxidation (DOX) of peanut protein isolates (PPIs) was measured as quantity of LA to generate LOS. This study analyzed the effect of lipid oxidation‐derived free radicals on the molecular structure and digestive properties of arachin and conarachin and observed substantial changes in carbonyl content, total sulfhydryl content, and number of disulfide bonds as quantities of LA increased, thus indicating significant oxidation of two proteins. Further, it was found that arachin was more stable than conarachin in a LOX‐catalyzed oxidizing system. When the amount of LA was 3 and 5 ml, the maximum surface hydrophobic characteristic values of arachin and conarachin reached the maximum, which were 235 ± 10 and 349 ± 13, respectively. This study laid a theoretical foundation for the application of peanut protein in food products. Practical applications: peanut protein has generated interest because it is the best source for the wall material for the preparation of nanoparticles and microcapsule particles due to its good biocompatibility and biodegradability, The structure‐activity relationship between arachin and conarachin is of great guiding significance for the improvement of peanut protein molecular modification and functional properties.This study laid a theoretical foundation for the application of peanut protein in food products. [ABSTRACT FROM AUTHOR]