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A review on potential heterocycles for the treatment of glioblastoma targeting receptor tyrosine kinases
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作者 NILAM BHUSARE MAUSHMI KUMAR 《Oncology Research》 SCIE 2024年第5期849-875,共27页
Glioblastoma,the most aggressive form of brain tumor,poses significant challenges in terms of treatment success and patient survival.Current treatment modalities for glioblastoma include radiation therapy,surgical int... Glioblastoma,the most aggressive form of brain tumor,poses significant challenges in terms of treatment success and patient survival.Current treatment modalities for glioblastoma include radiation therapy,surgical intervention,and chemotherapy.Unfortunately,the median survival rate remains dishearteningly low at 12–15 months.One of the major obstacles in treating glioblastoma is the recurrence of tumors,making chemotherapy the primary approach for secondary glioma patients.However,the efficacy of drugs is hampered by the presence of the blood-brain barrier and multidrug resistance mechanisms.Consequently,considerable research efforts have been directed toward understanding the underlying signaling pathways involved in glioma and developing targeted drugs.To tackle glioma,numerous studies have examined kinase-downstream signaling pathways such as RAS-RAF-MEKERK-MPAK.By targeting specific signaling pathways,heterocyclic compounds have demonstrated efficacy in glioma therapeutics.Additionally,key kinases including phosphatidylinositol 3-kinase(PI3K),serine/threonine kinase,cytoplasmic tyrosine kinase(CTK),receptor tyrosine kinase(RTK)and lipid kinase(LK)have been considered for investigation.These pathways play crucial roles in drug effectiveness in glioma treatment.Heterocyclic compounds,encompassing pyrimidine,thiazole,quinazoline,imidazole,indole,acridone,triazine,and other derivatives,have shown promising results in targeting these pathways.As part of this review,we propose exploring novel structures with low toxicity and high potency for glioma treatment.The development of these compounds should strive to overcome multidrug resistance mechanisms and efficiently penetrate the blood-brain barrier.By optimizing the chemical properties and designing compounds with enhanced drug-like characteristics,we can maximize their therapeutic value and minimize adverse effects.Considering the complex nature of glioblastoma,these novel structures should be rigorously tested and evaluated for their efficacy and safety profiles. 展开更多
关键词 GLIOBLASTOMA Kinase pathway PYRIMIDINE QUINAZOLINE heterocycles
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Assessment of electrostatic discharge sensitivity of nitrogen-rich heterocyclic energetic compounds and their salts as high energy-density dangerous compounds:A study of structural variables
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作者 Mohammad Hossein Keshavarz Sedigheh Heydari Bani +1 位作者 Reza Bakhtiari Seyyed Hesamodin Hosseini 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第9期15-22,共8页
Nitrogen-rich heterocyclic energetic compounds(NRHECs)and their salts have witnessed widespread synthesis in recent years.The substantial energy-density content within these compounds can lead to potentially dangerous... Nitrogen-rich heterocyclic energetic compounds(NRHECs)and their salts have witnessed widespread synthesis in recent years.The substantial energy-density content within these compounds can lead to potentially dangerous explosive reactions when subjected to external stimuli such as electrical discharge.Therefore,developing a reliable model for predicting their electrostatic discharge sensitivity(ESD)becomes imperative.This study proposes a novel and straightforward model based on the presence of specific groups(-NH_(2) or-NH-,-N=N^(+)-O^(-)and-NNO_(2),-ONO_(2) or-NO_(2))under certain conditions to assess the ESD of NRHECs and their salts,employing interpretable structural parameters.Utilizing a comprehensive dataset comprising 54 ESD measurements of NRHECs and their salts,divided into 49/5 training/test sets,the model achieves promising results.The Root Mean Square Error(RMSE),Mean Absolute Error(MAE),and Maximum Error for the training set are reported as 0.16 J,0.12 J,and 0.5 J,respectively.Notably,the ratios RMSE(training)/RMSE(test),MAE(training)/MAE(test),and Max Error(training)/Max Error(test)are all greater than 1.0,indicating the robust predictive capabilities of the model.The presented model demonstrates its efficacy in providing a reliable assessment of ESD for the targeted NRHECs and their salts,without the need for intricate computer codes or expert involvement. 展开更多
关键词 Electrostatic discharge sensitivity heterocyclic energetic compounds containing azole compound Interpretable structural parameter Safety
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Alkylene-functionality in bridged and fused nitrogen-rich poly-cyclic energetic materials:Synthesis,structural diversity and energetic properties
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作者 Man Xu Nanxi Xiang +2 位作者 Ping Yin Qi Lai Siping Pang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第5期18-46,共29页
From the standpoint of chemical structures,the organic backbones of energetic materials can be classified into aromatic rings,nonaromatic rings,and open chains.Although the category of aromatic energetic compounds exh... From the standpoint of chemical structures,the organic backbones of energetic materials can be classified into aromatic rings,nonaromatic rings,and open chains.Although the category of aromatic energetic compounds exhibits several advantages in the regulation of energetic properties,the nonaromatic heterocycles,assembling nitramino explosophores with simple alkyl bridges,still have prevailed in benchmark materials.The methylene bridge plays a pivotal role in the constructions of the classic nonaromatic heterocycle-based energetic compounds,e.g.,hexahydro-1,3,5-trinitro-1,3,5-triazine(RDX)and octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine(HMX),whereas ethylene bridge is the core moiety of state-of-the-art explosive 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane(CL-20).In this context,it is of great interest to employ simple and practical bridges to assemble aromatic and nonaromatic nitrogen-rich heterocycles,thereby expanding the structural diversity of energetic materials,e.g.,bridged and fused nitrogen-rich poly-heterocycles.Furthermore,alkyl-bridged poly-heterocycles highlight the potential for the open chain type of energetic materials.In this review,the development of alkyl bridges in linking nitrogen-rich heterocycles is presented,and the perspective of the newly constructed energetic backbones is summarized for the future design of advanced energetic materials. 展开更多
关键词 Energetic materials Alkyl bridge strategy nitrogen-rich azoles Fused heterocycles AZOLES
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Split Addition of Nitrogen-Rich Substrate at Thermophilic and Mesophilic Stages of Composting: Effect on Green House Gases Emission and Quality of Compost
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作者 Boakye Acheampong Kodwo Miezah +2 位作者 Enoch Bessah Benedicta Essel Ayamba Francis Kemausour 《Open Journal of Soil Science》 2024年第2期133-158,共26页
Composting as a solution to the increasing generation of municipal solid waste (MSW), also contribute to GHGs emission when not controlled and could lack some basic nutrients, especially nitrogen. This study assessed ... Composting as a solution to the increasing generation of municipal solid waste (MSW), also contribute to GHGs emission when not controlled and could lack some basic nutrients, especially nitrogen. This study assessed the split-additions of nitrogen-rich substrate to composting materials and their effect on GHGs emissions as well as the quality of the composts. Nitrogen-rich substrates formulated from pig and goat manure were co-composted with MSW for a 12-weeks period by split adding at mesophilic (˚C) and thermophilic (>50˚C) stages in five different treatments. Representative samples from the compost were taken from each treatment for physicochemical, heavy metals and bacteriological analysis. In-situ CH<sub>4</sub>, CO<sub>2</sub>, N<sub>2</sub>O gas emissions were also analyzed weekly during composting. It was observed that all the treatments showed significant organic matter decomposition, reaching thermophilic temperatures in the first week of composting. The absence affects the suitable agronomic properties. All nitrogen-rich substrate applied at thermophilic stage (Treatment two) recorded the highest N, P and K concentrations of 1.34%, 0.97% and 2.45%, respectively with highest nitrogen retention. In terms of GHG emissions, CO<sub>2</sub> was highest at the thermophilic stage when N-rich substrate was added in all treatment, while CH<sub>4</sub> was highest in the mesophilic stage with N-rich substrate addition. N<sub>2</sub>O showed no specific trend in the treatments. Split addition of the N-rich substrate for co-composting of MSW produced compost which is stable, has less nutrient loss and low GHG emissions. Split addition of a nitrogen-rich substrate could be an option for increasing the fertilizer value of MSW compost. 展开更多
关键词 COMPOST nitrogen-rich Substrate THERMOPHILIC MESOPHILIC Greenhouse Gas Emissions
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Binding interaction of phosphorus heterocycles with bovine serum albumin:A biochemical study 被引量:4
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作者 Swarup Roy Raj Kumar Nandi +2 位作者 Sintu Ganai K.C. Majumdar Tapan K. Das 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2017年第1期19-26,共8页
Interaction between bovine serum albumin(BSA) and phosphorus heterocycles(PHs) was studied using multispectroscopic techniques. The results indicated the high binding affinity of PHs to BSA as it quenches the intrinsi... Interaction between bovine serum albumin(BSA) and phosphorus heterocycles(PHs) was studied using multispectroscopic techniques. The results indicated the high binding affinity of PHs to BSA as it quenches the intrinsic fluorescence of BSA. The experimental data suggested the fluorescence quenching mechanism between PHs and BSA as a dynamic quenching. From the UV–vis studies, the apparent association constant(K_(app)) was found to be 9.25×10~2, 1.27×10~4and 9.01×10~2L/mol for the interaction of BSA with PH-1, PH-2 and PH-3,respectively. According to the F?rster's non-radiation energy transfer(FRET) theory, the binding distances between BSA and PHs were calculated. The binding distances(r) of PH-1, PH-2 and PH-3 were found to be2.86, 3.03, and 5.12 nm, respectively, indicating energy transfer occurs between BSA and PHs. The binding constants of the PHs obtained from the fluorescence quenching data were found to be decreased with increase of temperature. The negative values of the thermodynamic parameters ΔH, ΔS and ΔG at different temperatures revealed that the binding process is spontaneous; hydrogen bonds and van der Waals interaction were the main force to stabilize the complex. The microenvironment of the protein-binding site was studied by synchronous fluorescence and circular dichroism(CD) techniques and data indicated that the conformation of BSA changed in the presence of PHs. Finally, we studied the BSA-PHs docking using Auto Dock and results suggest that PHs is located in the cleft between the domains of BSA. 展开更多
关键词 BSA Spectroscopy Phosphorus heterocycles BSA-PHs DOCKING
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CuI/Proline-catalyzed N-Arylation of Nitrogen Heterocycles 被引量:2
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作者 Wei DENG Ye Feng WANG Chen ZHANG Lei LIU Qing Xiang GUO 《Chinese Chemical Letters》 SCIE CAS CSCD 2006年第3期313-316,共4页
Ma's CuI/proline procedure for the catalytic cross coupling between nitrogen heterocycles and aryl halides was markedly improved. The key finding was that K3PO4 was a much better base than K2CO3 for the reaction. Wit... Ma's CuI/proline procedure for the catalytic cross coupling between nitrogen heterocycles and aryl halides was markedly improved. The key finding was that K3PO4 was a much better base than K2CO3 for the reaction. With this new reaction condition the cross coupling with aryl iodides could be accomplished in 1,4-dioxane instead of DMSO. This reactin also could be carried out in DMF. Furthermore, the coupling yields under the new conditions are usually higher than in Ma's original methods. 展开更多
关键词 Cross coupling reaction CUI N-ARYLATION nitrogen heterocycle proline.
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Ligand Exchange Reaction of Ferrocene with Heterocycles 被引量:1
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作者 Yutaka Okada Hiroshi Huruya Yasuhiro Imori 《International Journal of Organic Chemistry》 2015年第4期282-290,共9页
The ligand exchange reaction with heterocycles containing nitrogen, oxygen or sulfur atoms was carried out. For the reaction with heterocycles, the order of the reactivity was S-heterocycles > N-heterocycles > O... The ligand exchange reaction with heterocycles containing nitrogen, oxygen or sulfur atoms was carried out. For the reaction with heterocycles, the order of the reactivity was S-heterocycles > N-heterocycles > O-heterocycles. Furthermore, when the results for the heterocycles were compared to those for the corresponding hydrocarbons, the hydrocarbons had a higher reactivity. These results mean that the reactivity would be mainly governed by the electron density of these arenes. 展开更多
关键词 FERROCENE LIGAND EXCHANGE REACTION heterocyclE
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Studies on Thiosemicarbazides and Related Heterocycles(ⅩⅩⅥ)──Synthesis of 3-[5'-amino-1'-(4"-chlorophenyl)-1',2',3'-triazol-4'-yl]-4-aryl-1,2,4-triazoline-5-thiones
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作者 ZHANG Zi yi, DONG Heng shan and GUAN Zuo wu (National Laboratory of Applied Organic Chemistry, Department of Chemistry, Lanzhou University, Lanzhou, 730000) YANG Shi yan (State Key Laboratory for Oxo Synthesis and Selective Oxidization, 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 1997年第1期29-35,共7页
The treatment of 5 amino 1 (4 chlorophenyl) 1,2,3 triazol 4 carbohydrazide with equimolecular aryl isothiocyanate gave new derivatives 1 a—l . Twelve title compounds were obtained in 42% to 87% yields whe... The treatment of 5 amino 1 (4 chlorophenyl) 1,2,3 triazol 4 carbohydrazide with equimolecular aryl isothiocyanate gave new derivatives 1 a—l . Twelve title compounds were obtained in 42% to 87% yields when compounds 1 a—l were respectively treated with sodium hydroxide aqueous solution(2 mol/L). The products of Dimroth rearrangement were not observed in the experiment. The structures of all the compounds were confirmed by means of IR, 1H NMR, MS and elementary analysis. 展开更多
关键词 Triazole 1 2 4 Triazoline 5 thione heterocyclE SYNTHESIS
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Theoretical Design of High-spin Organic Molecules with Heterocycles as Ferromagnetic Coupling Units
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作者 WANG Li-min ZHANG Jing-ping WANG Rong-shun 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2003年第4期508-511,共4页
Novel stable high spin molecules possessing three different arranged fashions are designed with - · N-N< as a spin-containing(SC) fragment, phenylene as an end group and various aromatic molecules, such as ben... Novel stable high spin molecules possessing three different arranged fashions are designed with - · N-N< as a spin-containing(SC) fragment, phenylene as an end group and various aromatic molecules, such as benzene(1), 2,6-pyridine(2), 3,5-pyridine(3), pyridazine(4), 4,6-pyrimidine(5), 2,6-pyrimidine(6), pyrazine(7) and triazine(8), as a ferromagnetic coupling(FC) unit. The effects of the different coupling units on the spin multiplicities of the ground states and their stabilities were investigated by means of AM1-CI approach. It has been found that the spin densities on the two atoms of the SC fragment are different from delocalization results in the specific stability of - · N-N<. In these molecules, the stabilities of the triplet states decrease when the distance between the atoms of central SC(-N-) increases. It is shown that the heterocycles as the coupling units have influence on the stabilities of the high-spin ground states. That the heteroatom lying in m -phenyl can improve ferromagnetic coupling, while the heteroatom lying in o -phenyl or p -phenyl is not in favor of the ferromagnetic coupling. 展开更多
关键词 heterocyclE Coupling unit BIRADICAL HIGH-SPIN AM1-CI B3LYP
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Cyclocondensation Reactions of Hydrazonoyl Chlorides with Some Azines: Synthesis of New Fused Heterocycles of Expected Microbiological Activity
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作者 Mosselhi A. M. Mohamed Liala M. B. Abu-Alola +1 位作者 Ohoud N. A. Al-Zaidi Hosam A. H. Saad 《International Journal of Organic Chemistry》 2017年第1期12-24,共13页
New functionalized fused heterocycles, such as, 1,3,6,9,11-pentasubstituted-pyrido[3,2-f:6,5-f']bis([1,2,4]triazolo[4,3-a]-pyrimidin-5(1H)-ones (6) and 1,3-disubstituted-7-[(E)-2-(thiophen-2-yl)ethenyl]-1,4,9,9a-t... New functionalized fused heterocycles, such as, 1,3,6,9,11-pentasubstituted-pyrido[3,2-f:6,5-f']bis([1,2,4]triazolo[4,3-a]-pyrimidin-5(1H)-ones (6) and 1,3-disubstituted-7-[(E)-2-(thiophen-2-yl)ethenyl]-1,4,9,9a-tetrahydro-6H-[1,2,4]triazino[4,3-b][1,2,4,5]-tetrazin-6-ones (16) were synthesized via reaction of the hydrazonoyl chlorides (1) with 1,3,6-triphenyl-9-thioxo-9,10-dihydro-pyrimido [4,5-b]pyrido[4,5-d][1,2,4]triazolo[4,3-a]pyrimidin-5,7(1H,8H)-di-one (5) and 4-amino-6-[(2-thiophen-2-yl)ethenyl]-3-thioxo-3,4-dihydro-[1,2,4]triazin-5(2H)-one (11), respectively. The mechanism and the regioselectivity of the studied reactions have been discussed. The biological activity of the products has been evaluated against some fungi and bacteria species. The tested compounds exhibited moderate activity against the bacteria species. 展开更多
关键词 Hydrazonoyl Chlorides AZINES FUSED heterocycles BIOLOGICAL ACTIVITY
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Microwave Irradiation Effect on the Ligand Exchange Reaction between Ferrocene and Heterocycles
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作者 Yutaka Okada Atsushi Niou Shinya Nakano 《Green and Sustainable Chemistry》 2017年第2期95-100,共6页
The ligand exchange reaction is a typical reaction of ferrocenes. This reaction proceeds via the abstraction of a cyclopentadienyl ring by a Lewis acid followed by coordination of an aromatic compound to the resulting... The ligand exchange reaction is a typical reaction of ferrocenes. This reaction proceeds via the abstraction of a cyclopentadienyl ring by a Lewis acid followed by coordination of an aromatic compound to the resulting species. This reaction with conventional heating requires a long reaction time. Furthermore, the reactions with heterocycles are lower than those with the corresponding hydrocarbons, and do not produce any products in some cases. In this paper, the ligand exchange reaction of ferrocene and a heterocyclic aromatic compound during microwave irradiation and its effect are discussed. As a result, for some heterocycles, the decrease in the reaction time was confirmed. Furthermore, under the microwave irradiation conditions, the tendency in which the difference in their reactivities became low was confirmed. 展开更多
关键词 MICROWAVE IRRADIATION Effect FERROCENE LIGAND Exchange heterocyclE
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The integration of dinitropyrazole and 1,3,4-oxadiazole:A novel hybrid heterocyclic skeleton for balancing energy and stability 被引量:1
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作者 Xiao-xiao Zheng Ting-ou Yan +2 位作者 Lei Qian Hong-wei Yang Guang-bin Cheng 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2023年第6期122-128,共7页
In this study,a new energetic hybrid skeleton was constructed through the integration of nitropyrazole and 1,3,4-oxadiazole skeletons in a molecule.Furthermore,the energetic precursor(2),the azo-bridged compound(3),th... In this study,a new energetic hybrid skeleton was constructed through the integration of nitropyrazole and 1,3,4-oxadiazole skeletons in a molecule.Furthermore,the energetic precursor(2),the azo-bridged compound(3),the neutral nitramine(4)and the corresponding energetic salts(5-7)were synthesized.Their physicochemical and energetic properties we re experimentally and theo retically evaluated.Among the developed compounds,the azo-bridged compound(3)and dihydroxylammoinium(6)display high detonation performances(3,D_(v)=8904 m/s,P=34.47 GPa;6,D_(v)=9025 m/s,P=34.66 GPa),moderate sensitivities(3,IS=16 J,FS=120 N;6,IS=20 J,FS=312 N)and good densities(3,1.87 g/cm^(3);6,1.81 g/cm^(3)),which indicates that they have the potential to replace the traditional high-energy explosive RDX.The results show that the integration of different energetic skeletons can achieve a good balance between energy and sensitivity. 展开更多
关键词 heterocyclE Azo-bridged Hybrid skeletons Energetic materials
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Synthesis and Photophysical Properties of Novel Highly Stable Zero/Bis-Zero Methine Cyanine Dyes Based on N-Bridgehead Heterocycles
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作者 Ahmed I. Koraiem Islam M. Abdellah Ahmed M. El-Shafei 《International Journal of Organic Chemistry》 2018年第3期282-297,共16页
Cyanine dyes of zero/bis-zero methine incorporating imid-azo(1,2-a)Pyridine (quinoline) or pyrazino(1,2-a)pyridine (quinoline) with stable C-N bond were synthesized using keto-oxime methylene C-link heterocyclic quate... Cyanine dyes of zero/bis-zero methine incorporating imid-azo(1,2-a)Pyridine (quinoline) or pyrazino(1,2-a)pyridine (quinoline) with stable C-N bond were synthesized using keto-oxime methylene C-link heterocyclic quaternary salts [1-phenyl-3-methyl-pyrazolino-4-keto-oxime-α-methylene-bis-pyridin-(quinoin)-1(4)-di-ium-iodide(ethiodide) salts and 1-phenyl-3-methyl-pyrazolino- 4-ketooxime-α-methylene-N-2-methyl-bis pyridin (quinoin)-1(4)-di-ium-iodide(ethiodide) salts]. Such heterocyclic precursors and related dyes were identified by elemental and spectral analyses. The absorption spectra properties of such dyes were investigated in 95% Ethanol to attempt and throw some light on the influence of such new heterocyclic nuclei and to compare or evaluate spectral behaviors. The absorption spectra of dyes in different pure solvents were examined in the visible region showing solvatochromism and the colour changes of dyes with solvents having different polarities. This permits a selection of the optimal solvent (fractional solvent) when such dyes are applied as photosensitizers. The spectral behavior of some selected newly synthesized cyanine dyes is observed in mixed solvents of different polarities and progressively increasing quantities of one solvent over the other were studied and showed an increase in the absorbance of CT band with increasing proportion of that solvent. Evidence for hydrogen bond formation between the solute molecules and solvent molecules allows measurement of certain energies such as hydrogen bonding, orientation, and free energies. 展开更多
关键词 N-Bridgehead heterocycles Cyanine Dyes Zero/Bis-Zero Methine SOLVATOCHROMIC Behaviours
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Radical denitrogenative transformations of polynitrogen heterocycles:Building C–N bonds and beyond
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作者 Wen-Chao Yang Cai-Yun Chen +1 位作者 Jun-Feng Li Zu-Li Wang 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2021年第11期1865-1875,共11页
Polynitrogen heterocycles are readily available and have recently arisen as versatile synthons for the formation of various C-C and C-X bonds,and medicinally active nitrogen-containing heterocycles.Several cascade rea... Polynitrogen heterocycles are readily available and have recently arisen as versatile synthons for the formation of various C-C and C-X bonds,and medicinally active nitrogen-containing heterocycles.Several cascade reactions,including annulation,radical cascade,and borylation reactions,have been reported in which polynitrogen heterocycles are applied as arylation reagents.The success of these exceptional reactions illustrates the great synthetic potential of polynitrogen heterocycles,which provides a direct and useful approach to arylation reactions and the synthesis of nitrogen-containing heterocycles.The use of photocatalysts to effectively transfer energy from visible light to non-absorbing compounds has gained increasing attention as this method allows for the mild and efficient generation of radicals in a controlled manner.This approach has thus led to new methods that involve unique bond formation reactions.In addition,the use of free radical intermediates stabilized by transition metal catalysts is a powerful way to construct new chemical bonds.The aim of this review is to highlight the rapidly expanding area of radical-initiated denitrogenative cascade reactions of polynitrogen heterocycles and elaborate on their mechanisms from a new perspective by using photocatalysis and metal-based catalysis. 展开更多
关键词 Denitrogenation C-N bond CYCLIZATION Polynitrogen heterocycles RADICAL
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Spectroscopic studies of the interaction between phosphorus heterocycles and cytochrome P450
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作者 Dumei Ma Libo Zhang +2 位作者 Yingwu Yin Yuxing Gao Qian Wang 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2021年第6期757-763,共7页
P450 fatty acid decarboxylase Ole T from Staphylococcus aureus(Ole TSA)is a novel cytochrome P450 enzyme that catalyzes the oxidative decarboxylation of fatty acids to yield primarily terminal alkenes and CO_(2) or mi... P450 fatty acid decarboxylase Ole T from Staphylococcus aureus(Ole TSA)is a novel cytochrome P450 enzyme that catalyzes the oxidative decarboxylation of fatty acids to yield primarily terminal alkenes and CO_(2) or minor a-andβ-hydroxylated fatty acids as side-products.In this work,the interactions between a series of cycloalkyl phosphorus heterocycles(CPHs)and Ole TSAwere investigated in detail by fluorescence titration experiment,ultraviolet-visible(UV-vis)and31 P NMR spectroscopies.Fluorescence titration experiment results clearly showed that a dynamic quenching occurred when CPH-6,a representative CPHs,interacted with Ole TSAwith a binding constant value of 15.2×104 M-1 at 293 K.The thermodynamic parameters(ΔH,ΔS andΔG)showed that the hydrogen bond and van der Waals force played major roles in the interaction between Ole TSAand CPHs.The UV-vis and31 P NMR studies indicated the penetration of CPH-6 into the interior environment of Ole TSA,which greatly affects the enzymatic activity of Ole TSA.Therefore,our study revealed an effective way to use phosphorus heterocyclic compounds to modulate the activity of cytochrome P450 enzymes. 展开更多
关键词 Phosphorus heterocycles Cytochrome P450 Ole T INTERACTION SPECTROSCOPY
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Theoretical design of high-spin biradical molecules with heterocycles as coupling unit
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作者 王立敏 储德清 +1 位作者 张景萍 王荣顺 《中国有色金属学会会刊:英文版》 CSCD 2006年第B02期715-718,共4页
Computational studies of a class of potentially stable high-spin biradicals that two-atom-three-electron spin centers SC units connected by heterocycles FC and phenyl EG were described. The geometry and character of t... Computational studies of a class of potentially stable high-spin biradicals that two-atom-three-electron spin centers SC units connected by heterocycles FC and phenyl EG were described. The geometry and character of the spin exchange interaction were obtained by means of UB3LYP/6-31G*. The results show that the molecules possessing three different arranged fashions are designed with -·N-S as SC fragment, pyridine as FC and phenyl as EG, the spin densities on the two atoms of the SC fragment are different from the delocalization results in the specific stability of-·N-S. In these molecules, the stabilities of the triplet states decrease when the distance between the atoms of central SC (-N-) increases. Molecules with -·N-S as SC fragment, pyridine, pyrazine and triazine as FC and phenyl as EG are designed, the stability of triplet states for the molecule with pyridine as FC is the highest, and that for the molecule with pyrazine as FC is the lowest. Molecules with -·N-S, -·N-O and -·N-NH as SC fragment, pyridine as FC and phenyl as EG are designed, the stability of triplet states for the molecule with -·N-S as SC is the highest, that for the molecule with -·N-NH as SC is the lowest. 展开更多
关键词 杂环化合物 铁磁耦合单元 高自旋双游离基分子 理论设计
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The role of flavonoids in mitigating food originated heterocyclic aromatic amines that concerns human wellness
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作者 Hui Teng Hongting Deng +3 位作者 Chang Zhang Hui Cao Qun Huang Lei Chen 《Food Science and Human Wellness》 SCIE CSCD 2023年第4期975-985,共11页
Meat products are an important part in our daily diet,providing valuable nutrients for the human body.However,heating processes cause the meat to become more appetizing with changes in texture,appearance,flavor,and ch... Meat products are an important part in our daily diet,providing valuable nutrients for the human body.However,heating processes cause the meat to become more appetizing with changes in texture,appearance,flavor,and chemical properties by the altering of protein structure and other ingredients.As one kind of cooking-induced contaminants,heterocyclic aromatic amines(HAAs)are widely present in protein aceous food products with strong carcinogenic and mutagenic properties.In order to promote the safety of traditional meat products,this review focused on the formation,metabolism,biological monitoring and inhibitory mechanism of HAA.An overview of the formation pathways,hazards,and control methods of HAAs during food processing in recent years was studied,aiming to provide some valuable information for exploring effective methods to inhibit the production of associated hazards during food processing.Systematic selection of different types of flavonoids to explore their effects on the formation of HAAs in an actual barbecue system can provide theoretical reference for effectively controlling the formation of HAAs and reducing their harm to human health. 展开更多
关键词 heterocyclic aromatic amines FLAVONOIDS Hazardous control Precursors
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以“芬太尼”事件为载体的杂环化学课程思政的探索与实践
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作者 刘幸海 武宏科 《大学化学》 CAS 2024年第8期359-364,共6页
以“芬太尼”事件为载体,通过发掘和利用阿片类杂环化合物的思政案例,加强知识传授、价值引领与科普相结合,完善杂环化学课程体系建设。用已知的阿片类异喹啉杂环药物作为案例,将异喹啉杂环的理化性质、制备及其应用贯穿于教学的全过程... 以“芬太尼”事件为载体,通过发掘和利用阿片类杂环化合物的思政案例,加强知识传授、价值引领与科普相结合,完善杂环化学课程体系建设。用已知的阿片类异喹啉杂环药物作为案例,将异喹啉杂环的理化性质、制备及其应用贯穿于教学的全过程。通过案例教学法对杂环化学课程教学进行改革,充分调动学生学习杂环化学的兴趣,明显改善教学效果。 展开更多
关键词 杂环化学 案例教学 阿片类杂环药物 课程思政
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伊立替康药物中间体7-乙基喜树碱合成的课程思政设计
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作者 刘志莲 王文贵 +2 位作者 杨红晓 崔玉 王守锋 《大学化学》 CAS 2024年第2期89-93,共5页
抗癌药物伊立替康中间体7-乙基喜树碱的合成是杂环芳烃的烷基化反应。本案例通过将实验过程与药物合成和“健康中国”相关联,对实验进行了创新性的思政融入设计。师生全员在案例的导入、研讨、实施、反思与考核的全过程进行全方位的课... 抗癌药物伊立替康中间体7-乙基喜树碱的合成是杂环芳烃的烷基化反应。本案例通过将实验过程与药物合成和“健康中国”相关联,对实验进行了创新性的思政融入设计。师生全员在案例的导入、研讨、实施、反思与考核的全过程进行全方位的课程思政教育,解决了实验课只注重实验内容而忽略思政教育的问题,实现了“三全育人”。在此过程中不仅激发了学生的学习兴趣,有效地进行了科学思维和创新思维的训练,培养了学生的探索精神和创新意识,而且强化了学生提高原子利用率的绿色化学意识、环保意识和可持续发展意识,提升了学生为健康中国贡献力量的责任感和使命感,坚定了学生运用所学专业知识服务国家的决心和信心。 展开更多
关键词 杂环芳烃 烷基化 绿色化学 课程思政
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功能化氮杂环卡宾聚合树脂对Cu^(2+)的吸附研究
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作者 伍婵翠 蔡怀然 +3 位作者 李学军 陈培博 黄健 梁英 《环境科学与技术》 CAS CSCD 北大核心 2024年第3期208-218,共11页
该研究制备了功能化氮杂环卡宾聚合树脂(PNO),旨在去除废水中Cu^(2+);基于静态和动态吸附实验,研究了PNO对废水中Cu^(2+)的吸附效果。结果表明:PNO对Cu^(2+)的最佳吸附条件为吸附剂投加量100 mg、吸附时间30 min、pH值4.0~5.9、温度298 ... 该研究制备了功能化氮杂环卡宾聚合树脂(PNO),旨在去除废水中Cu^(2+);基于静态和动态吸附实验,研究了PNO对废水中Cu^(2+)的吸附效果。结果表明:PNO对Cu^(2+)的最佳吸附条件为吸附剂投加量100 mg、吸附时间30 min、pH值4.0~5.9、温度298 K、转速150 r/min,最大吸附量为51.55 mg/g。PNO对Cu^(2+)的吸附过程符合Langmuir、Freundlich等温吸附模型和准二级动力学模型。动态吸附量随柱高增加、流速降低和进水Cu^(2+)浓度增加而增大。使用Thomas和Bohart-Adams模型拟合,相关系数R^(2)均大于0.92,预测值与实验值相符。经过5次静态吸附-解吸和3次动态循环再生后,PNO对Cu^(2+)的去除率仍达到第一次循环的96%以上,去除效果和再生性能良好。PNO对含铜废水高效处理具有广泛的应用前景。 展开更多
关键词 功能化氮杂环卡宾聚合树脂 Cu^(2+) 吸附性能 吸附模型
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