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Nitrogenous compounds have been extensively utilized as hydrogen atom transfer (HAT) catalysts in photoredox reactions, with nitrogenous radical cations being the actual hydrogen atom abstractors. Building upon our previous work, 120 thermodynamic graphs of nitrogenous radical cations abstracting hydrogen atoms, which encompass seven vital thermodynamic parameters, are designed and established to elucidate their redox characteristics. Furthermore, the applications of thermodynamic graphs to select appropriate photocatalysts, assess the feasibility of the HAT process, and diagnose the possible activation mechanism were discussed, which would enable the utilities of nitrogenous compounds as HAT catalysts or nitrogenous radical cations as hydrogen atom abstractors in photoredox reactions. [ABSTRACT FROM AUTHOR]

Dipines are a type of important antihypertensive drug as L-calcium channel blockers, whose core skeleton is the 1,4-dihydropyridine structure. Since the dihydropyridine ring is a key structural factor for biological activity, the thermodynamics of the aromatization dihydropyridine ring is a significant feature parameter for understanding the mechanism and pathways of dipine metabolism in vivo. Herein, 4-substituted-phenyl-2,6-dimethyl-3,5-diethyl-formate-1,4-dihydropyridines are refined as the structurally closest dipine models to investigate the thermodynamic potential of dipine oxidative metabolism. In this work, the thermodynamic cards of dipine models' aromatization on 21 potential elementary steps in acetonitrile have been established. Based on the thermodynamic cards, the thermodynamic properties of dipine models and related intermediates acting as electrons, hydrides, hydrogen atoms, protons, and two hydrogen ions (atoms) donors are discussed. Moreover, the thermodynamic cards are applied to evaluate the redox properties, and judge or reveal the possible oxidative mechanism of dipine models. [ABSTRACT FROM AUTHOR]

The intrinsic resistance energy ΔG≠XH/X of H‐donor XH in hydrogen atom transfer (HAT) reaction is usually used to evaluate the kinetic H‐donating ability. In this article, a new method for determining ΔG≠XH/X of H‐donor in HAT reaction was proposed by the definition of thermo‐kinetic parameter ΔG≠o (XH) = 1/2[ΔG≠XH/X + ΔGo (XH)]. ΔG≠o (XH) is the characteristic physical parameter of XH to describe the H‐donating ability in a chemical reaction during a certain reaction time, ΔGo (XH) is the bond dissociation free energy. The kinetic studies of HATs between 20 alcohols, ethers, alkanes and amines (XH) with cumyloxyl radical [PhC (CH3)2O•, CumO•] were researched, and ΔGo (XH), ΔG≠XH/X, and ΔG≠o (XH) were used to investigate the H‐donating abilities of the studied substrates in thermodynamics, kinetics, and HAT reaction. The effect of structures of XH on these three parameters, the structure–activity relationship, such as the influence of electronic, steric, polar and stereoelectronic effects of substituents, heteroatoms insertion in cycloalkanes, and cis–trans configurational isomerism on the H‐donating abilities were discussed in detail. This study not only provides a new method for determining ΔG≠XH/X but also systematically studies the factors affecting the H‐donating ability, laying a foundation for the selection, design, and synthesis of more efficient antioxidants. [ABSTRACT FROM AUTHOR]

As the mechanisms of the hydride transfer reaction between 7,8‐dihydro‐9‐methylcaffeine (CAFH) with N‐methylacridinium (AcrH+ClO4‐) and hydrogen atom transfer (HAT) reaction between 2,3‐dihydrobenzo‐imidazoles (BIH) with 2,2‐diphenyl‐1‐picrylhydrazyl radical (DPPH•) were researched to both be induced by electron transfer, the reaction mechanisms of 2,3‐dihydrobenzo‐thiazoles (BTH) with these two substrates were studied. The thermodynamic analysis platforms were used to judge the mechanisms, and the mechanisms of these two reactions were not the same with CAFH and BIH as the Eox (BTH) value was more positive than CAFH and BIH. A new method for inferring the reaction mechanism was proposed using the kinetic equation ΔG≠XH/Y = ΔG≠o (XH) + ΔG≠o(Y) and thermo‐kinetic parameter ΔG≠o. The HAT reaction mechanisms between BTH with DPPH• and tBu3PhO• were researched by ΔG≠oHD. As the ΔG≠o (BTH) values in these two reactions were similar; hence, the rate determining steps of them were both HATs as the ΔG≠oHD(Y) values of DPPH• and tBu3PhO• used for determining ΔG≠o (BTH) were both in HAT reactions. The HAT reaction mechanisms between BIH with tBu3PhO• were also researched by thermodynamic analysis platform and kinetic isotope effect (KIE = 3.99), which confirmed that the rate determining step of BIH/tBu3PhO• was indeed HAT. The H‐donating ability of BIH and BTH was compared by ΔG≠oHD. From BIH to BTH, the substitution of N by S not only greatly reduces the thermodynamic electron donating and H‐donating capacity of the compound but also increases the H‐donating ability in kinetics and HAT reaction. [ABSTRACT FROM AUTHOR]

Hydrogen atom‐donating ability of alkane is a research hotspot and has been extensively studied. In this article, the second‐order rate constants of 20 hydrogen atom transfer (HAT) reactions between aliphatic, benzylic, and allylic alkanes and alkane derivatives with CumO• in acetonitrile at 298 K were studied. The thermo‐kinetic parameter ΔG≠o(XH), bond dissociation free energy ΔGo(XH), and kinetic intrinsic resistance energy ΔG≠XH/X were determined and used to evaluate the H‐donating abilities of these substrates in thermodynamics, kinetics, and HAT reactions. Structure–activity relationships including the factors (electronic, stereoelectronic, and steric effects), introduction of CH3, Ph, or Cl in alkanes, and introduction of N atom in cycloalkane were discussed carefully. The results show that the order of H‐donating abilities is allylic alkanes > cycloalkanes > chain alkanes ≈ benzylic alkanes > haloalkanes. The introduction of CH3, Ph, or Cl in alkanes and the introduction of N atom to the carbon ring reduce ΔGo(XH) but increase ΔG≠XH/X, and ΔG≠o(XH) is the synthesis result of these two parameters. The reliability of ΔG≠o(XH) was verified, and the accuracy and reliability of the parameters were proved. Through the study of this paper, not only the ΔGo(XH), ΔG≠XH/X, and ΔG≠o(XH) of these alkanes and derivatives in HAT reaction can be quantitatively evaluated but also the structure–activity relationship of alkane is clearly researched. [ABSTRACT FROM AUTHOR]

The study was to investigate in vitro and in vivo antibacterial effect andantibacterial mechanism of selenide Glycyrrhiza polysaccharide (SeGUP) and Glycyrrhiza polysaccharide (GUP) combined with antibiotics against Proteus mirabilis (PM). In vitro and in vivo bacteriostatic effect of SeGUP and GUP were analyzed by drug susceptibility test, minimum inhibitory concentration (MIC), growth curve, in vitro synergy, and effect of SeGUP and GUP on mortality of PM-infected mice. Bacteriostasis mechanism was analyzed by studying changes of PM cell wall, cell membrane, biofilm and antioxidant enzyme activities. The results showed that compared with GUP, SeGUP at same concentration had a larger inhibitory circle and a smaller MIC, which inhibited the growth of PM more strongly. SeGUP combined with CI showed a synergistic effect, while GUP combined with CI showed a additive effect. SeGUP extremely reduced mortality of PMinfected mice (P<0.01). Compared with control group, SeGUP, GUP, CI could extremely increase the activity of alkaline phosphatase (AKP), β -galactosidase (β -gal) and protein content in culture medium (P<0.01), extremely reduced intracellular DNA concentration, inhibited biofilm formation, reduced activity of catalase (CAT) and superoxide dismutase (SOD) (P<0.01). The study indicates that in vitro and in vivo antibacterial effect of SeGUP and its antibacterial mechanism are better than that of GUP. [ABSTRACT FROM AUTHOR]

Corn-soybean meal diet is one of the common types of livestock and poultry diets in China. In recent years, the stock of corn has declined year by year, leading to the high price of corn and the rising breeding cost. Therefore, it is of great significance to adopt non corn-soybean meal diets for the development of Chinese feed industry. Sorghum has relatively high energy value and protein content, which can replace part of corn and soybean meal in livestock and poultry diets, reduce the use of corn and soybean meal, and alleviate the pressure of insufficient supply of feed materials. The paper analyzes the nutritional value and anti-nutritional factors of sorghum, and expounds the application progress of sorghum in pig production at home and abroad in recent years, to provide reference for the application of sorghum in pig feed production. [ABSTRACT FROM AUTHOR]

Mononuclear nonheme high-valent (FeO) 2+ complexes participate in many enzymatic oxidation-reduction cycles in a living body and play a key role in organic synthesis. The concept of molecular ID (molecular identities) was proposed and applied in our previous work; it covers all thermodynamic data for compounds containing an active carbon-hydrogen bond: oxidation potential, hydride anion affinity, proton affinity, and hydrogen atom affinity. To facilitate quantitative analysis of the physical organic chemistry and molecular biology properties of (FeO) 2+ complexes, the molecular identities and reaction thermodynamic platform of representative complexes were established based on the thermodynamic data, such as (N4Py)(FeO) 2+ and (Bn-TPEN)(FeO) 2+ , and their kinetic characteristics. Finally, the findings of this study are as follows: first, the reaction between (N4Py)(FeO) 2+ and hydride donors 1 / 2 (Scheme 1) followed a one-step hydride anion transfer mechanism. The reactions between (N4Py)(FeO) 2+ and hydride donors 3 (Scheme 1) and between (Bn-TPEN)(FeO) 2+ and hydride donors 1 followed the hydrogen atom-electron transfer mechanism. Second, by comparison of high-valent (RuO) 2+ complexes and organic hydride acceptors, the essential laws in selecting the reaction mechanism were obtained to determine the reaction mechanism of this study. Third, the reaction between (N4Py)(FeO) 2+ and 1 followed the electron-proton-electron transfer mechanism under acidic conditions., Competing Interests: The authors declare no competing financial interest., (© 2025 The Authors. Published by American Chemical Society.)

The generic diagnostic characters of Paracercopis (Hemiptera: Cercopoidea: Cercopidae) are redefined and the autapomorphies are proposed to support the monophyly of the genus. Scanning electron micrographs of antennal sensilla and sensilla on rostral apex of P. seminigra (Melichar, 1902) are provided for the first time. A checklist together with new distribution records and key to the species of the genus are provided. Host plant associations of Paracercopis species are reported for the first time. Paracercopis unicolor Liang, Zhang & Xiao, sp. nov., representing the seventh and largest species of the genus is described from Hubei Province in south central China.

Nitrogen-containing heterocycles are an important class of antioxidants, and their reactivity and selectivity in hydrogen atom reactions have attracted significant interest from chemists. In this work, the kinetics of hydrogen atom transfer reactions from C(sp 3 )-H bonds of 28 nitrogen-containing heterocycles, oxygen-containing heterocycles, alicyclic amines and cycloalkanes, which were denoted as XH, to the CumO˙ radical, were investigated. The characteristic physical parameter of the substrate, i.e. , the thermo-kinetic parameter Δ G ≠o (XH), was determined using the kinetic equation [Δ G ≠ XH/Y = Δ G ≠o (XH) + Δ G ≠o (Y)] to quantitatively evaluate the H-donating ability of XH. The effects of the substrate structure, substituent attached to the nitrogen atom, and ring size on the H-donating ability were discussed carefully. By comparing the H-donating abilities of cycloalkanes, alicyclic amines and nitrogen/oxygen-containing heterocycles, the influence of the introduction of N, O, or carbonyl groups in the carbon ring on the H-donating ability of C(sp 3 )-H bond was determined. The electronic, steric and stereo-electronic effects of the groups were also discussed. Herein, we not only quantitatively determined the H-donating ability of the substrate, but also provided ideas for the synthesis of new antioxidants., Competing Interests: The authors declare no competing financial interests., (This journal is © The Royal Society of Chemistry.)

Ultra-high-performance liquid chromatography-Q exactive orbitrap tandem mass spectrometry(UHPLC-QEOrbitrap-MS/MS) was used to explore the inhibitory effect and mechanism of ginkgo flavone aglycone(GA) combined with doxorubicin(DOX) on H22 cells. The effects of different concentrations of GA and DOX on the viability of H22 cells were investigated, and combination index(CI) was used to evaluate the effects. In the experiments, control(CON) group, DOX group, GA group, and combined GA and DOX(GDOX) group were constructed. Then the metabolomics strategy was employed to explore the metabolic markers that were significantly changed after combination therapy on the basis of single medication treatment, and by analyzing their biological significance, the effect and mechanism of the anti-tumor effect of GA combined with DOX were explained. The results revealed that when 30 μg·mL~(-1) GA and 0.5 μmol·L~(-1) DOX was determined as the co-administration concentration, the CI value was 0.808, indicating that the combination of GA and DOX had a synergistic anti-tumor effect. Metabolomics analysis identified 23 metabolic markers, including L-arginine, L-tyrosine and L-valine, mostly amino acids. Compared with the CON group, 22 and 17 metabolic markers were significantly down-regulated after DOX treatment and GA treatment, respectively. Compared with the DOX and GA groups, the treatment of GA combined with DOX further down-regulated the levels of these metabolic markers in liver cancer, which might contribute to the synergistic effect of the two. Five key metabolic pathways were found in pathway enrichment analysis, including glutathione metabolism, phenylalanine metabolism, arginine and proline metabolism, β-alanine metabolism, and valine, leucine and isoleucine degradation. These findings demonstrated that the combination of GA and DOX remarkably inhibited the viability of H22 cells and exerted a synergistic anti-tumor effect. The mechanism might be related to the influence of the energy supply of tumor cells by interfering with the metabolism of various amino acids.