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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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Annulation Cascades of Cyclosulfonium Salts and Alkenes towards Sulfur-Containing N-Heterocycles by Visible Light/Copper Catalysis
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作者 Jie Ma Xufeng Li +4 位作者 Yuqing Chen Yongjia Shi Xiuyan Song Jian Lv Daoshan Yang 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2024年第14期1637-1643,共7页
Although,great achievements have been made in the synthesis of heterocycles using radical addition/cyclization strategy,developing versatile alkyl radical precursors,especially the non-stabilized long chain alkyl radi... Although,great achievements have been made in the synthesis of heterocycles using radical addition/cyclization strategy,developing versatile alkyl radical precursors,especially the non-stabilized long chain alkyl radicals for this strategy still remains a huge challenge.Herein,we report an efficient annulation cascade reaction between cyclosulfonium salts and alkenes for the synthesis of sulfur-containing N-heterocycles by visible light/copper catalysis under mild conditions.The C—S bond cleavage/radical cascade reaction delivers a variety of corresponding N-heterocycles containing aryl alkyl thioether motifs with good functional group tolerance.Significantly,the current system could be used for the late-stage functionalization of complex bioactive molecules. 展开更多
关键词 Visible light Radical reactions C-C coupling Sulfur heterocycles Photoredox catalysis
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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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Sulfur phase and sulfur removal in high sulfur-containing bauxite 被引量:15
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作者 胡小莲 陈文汨 谢巧玲 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第7期1641-1647,共7页
The sulfur phase in high sulfur-containing bauxite was studied by an X-ray diffraction analysis and a chemistry quantitative analysis.The methods for the removal of different shaped sulfur were also discussed.The resu... The sulfur phase in high sulfur-containing bauxite was studied by an X-ray diffraction analysis and a chemistry quantitative analysis.The methods for the removal of different shaped sulfur were also discussed.The results show that sulfur phases in high sulfur-containing bauxites exist in the main form of sulfide sulfur (pyrite) or sulfate sulfur,and the main sulfur forms of bauxites from different regions are not the same.Through a combination of an X-ray diffraction analysis and a chemistry quantitative analysis,the sulfur phases of high sulfur-containing bauxite could be accurately investigated.Deciding the main sulfur form of high sulfur-containing bauxite could provide theoretical instruction for choosing methods for the removal of sulfur from bauxite,and an oxidizing-roasting process is an effective way to remove sulfide sulfur from high sulfur-containing bauxite,the content of S^2-in crude ore in the digestion liquor is above 1.7 g/L,but in the roasted ore digestion liquor,it is below 0.18 g/L.Using the sodium carbonate solution washing technology to wash bauxite can effectively remove sulfate sulfur,the content of the total sulfur in ore is lowered to below 0.2% and can meet the production requirements for the sulfur content. 展开更多
关键词 high sulfur-containing bauxite sulfur phase oxidizing-roasting sodium carbonate solution washing technology
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Highly Efficient and Selective Removal of Pb(II) ions by Sulfur-Containing Calcium Phosphate Nanoparticles 被引量:1
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作者 龚成云 耿志刚 +3 位作者 董安乐 叶新新 汪国忠 张云霞 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2016年第5期607-616,I0002,共11页
A facile one-step co-precipitation method was demonstrated to fabricate amorphous sulfurcontaining calcium phosphate (SCP) nanoparticles, in which the sulfur group was in-situ introduced into calcium phosphate. The ... A facile one-step co-precipitation method was demonstrated to fabricate amorphous sulfurcontaining calcium phosphate (SCP) nanoparticles, in which the sulfur group was in-situ introduced into calcium phosphate. The resulting SCP exhibited a noticeable enhanced performance for Pb(II) removal in comparison with hydroxyapatite (HAP), being capable of easily reducing 20 ppm of Pb(II) to below the acceptable standard for drinking water within less than 10 min. Remarkably, the saturated removal capacities of Pb(II) on SCP were as high as 1720.57 mg/g calculated by the Langmuir isotherm model, exceeding largely that of the previously reported absorbents. Significantly, SCP displayed highly selective removal ability toward Pb(II) ions in the presence of the competing metal ions (Ni(II), Co(II), Zn(II), and Cd(II)). Further investigations indicated that such ultra-high removal efficiency and preferable affinity of Pb(II) ions on SCP may be reasonably ascribed to the formation of rodlike hydroxypyromorphite crystals on the surface of SCP via dissolution-precipitation and ion exchange reactions, accompanied by the presence of lead sulfide precipitates. High removal efficiency, fast removal kinetics and excellent selectivity toward Pb(II) made the obtained SCP material an ideal candidate for Pb(II) ions decontamination in practical application. 展开更多
关键词 sulfur-containing calcium phosphate Pb(II) ions Selective removal
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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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A review of gold extraction using noncyanide lixiviants: Fundamentals, advancements, and challenges toward alkaline sulfur-containing leaching agents 被引量:11
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作者 Chun-bao Sun Xiao-liang Zhang +1 位作者 Jue Kou Yi Xing 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2020年第4期417-431,共15页
Alkaline sulfur-containing lixiviants,including thiosulfate,polysulfides,and alkaline sulfide solutions,stand out as a promising class of alternatives to cyanide because of their low toxicity,high efficiency,and stron... Alkaline sulfur-containing lixiviants,including thiosulfate,polysulfides,and alkaline sulfide solutions,stand out as a promising class of alternatives to cyanide because of their low toxicity,high efficiency,and strong adaptability.In this paper,we summarized the research progress and remaining challenges in gold extraction using these noncyanide reagents.After a brief introduction to the preparation method,the transformation process of various sulfur-containing species in alkaline solutions was discussed.Thereafter,some insights into the mechanism of gold leaching in alkaline sulfur-containing solutions were presented from different aspects,including thermodynamics analysis,electrochemical dissolution,and leaching kinetics.Moreover,recent progress in in-situ generation of sulfur-containing anions from gold-bearing sulfide minerals was outlined as well.Gold passivation caused by sulfur species was discussed in particular because it is considered the greatest challenge facing sulfur-containing leaching systems.Alkaline sulfur-containing lixiviants are expected to serve as alternatives in industrial applications of gold extraction,particularly for refractory gold ores containing copper and carbonaceous matter. 展开更多
关键词 GOLD extraction sulfur-containing lixiviants degradation in-situ generation PASSIVATION
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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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Synthesis and cytotoxic activity of heterocycle-substituted phthalimide derivatives 被引量:1
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作者 Ya Jun Yang Ya Nan Yang +4 位作者 Jian Shuang Jiang Zi Ming Feng Hong Yan Liu Xian Dao Pan Pei Cheng Zhang 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第8期902-904,共3页
A series of heterocycle-substituted phthalimide derivatives were synthesized.Structurally diverse derivatives with heterocyclic rings,including furan,imidazo[1,2-a]pyridine,1,3,4-thiadiazine,imidazo[2,1-b][1,3,4]thiad... A series of heterocycle-substituted phthalimide derivatives were synthesized.Structurally diverse derivatives with heterocyclic rings,including furan,imidazo[1,2-a]pyridine,1,3,4-thiadiazine,imidazo[2,1-b][1,3,4]thiadiazine,pyrazole,1,2,4-triazolo[3,4- b][1,3,4]thiadiazine,thiazole and thiazoline,were obtained by the reactions ofα-bromoketone intermediate with various nucleophiles containing oxygen,nitrogen and sulfur atom.Their cytotoxic activity was also evaluated against five human cancer cell lines in vitro. 展开更多
关键词 PHTHALIMIDE heterocycle α-Bromoketone Cytotoxic activity
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pH variation mechanism of high sulfur-containing bauxite 被引量:2
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作者 陈兴华 胡岳华 +2 位作者 李旺兴 陈湘清 曹学锋 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第8期2909-2913,共5页
In order to fundamentally solve the acidification problem of high sulfur-containing bauxite during storage, by simulating the environment of minerals storage in laboratory, the acidification mechanism and influencing ... In order to fundamentally solve the acidification problem of high sulfur-containing bauxite during storage, by simulating the environment of minerals storage in laboratory, the acidification mechanism and influencing factors of high sulfur-containing bauxite were studied and confirmed using the single variable method to control the atmosphere, water and other variables. The results show that the acidification is mostly caused by the oxidation of sulfur-containing bauxite, which is mainly the natural oxidation of Pyrite(Fe S2), then the alkaline minerals dissolute in the presence of water, leading to the acidification phenomenon, which is influenced by moisture and air flow. Finally, more acid-producing substances are formed, resulting in the acidification of high sulfur-containing bauxite. The acidification of high sulfur-containing bauxite results from the combined effect of the oxygen in the air and water, which can be significantly alleviated by controlling the diffusion of the oxygen in air. 展开更多
关键词 high sulfur-containing bauxite PYRITE acidification mechanism
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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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Synthesis and Characterization of New Schiff Bases Formed by Condensation of 2,9-Phenathroline-1,10-dialdehyde with Sulfur-Containing Amines 被引量:2
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作者 Md. Arifuzzaman Mohammad R. Karim +2 位作者 Tasneem A. Siddiquee Aminul H. Mirza Mohamad A. Ali 《International Journal of Organic Chemistry》 2013年第1期81-86,共6页
Four new Schiff bases of 1,10-phenanthroline-2,9-dicarboxaldehyde with sulfur-containing amines such as 2-mercaptoaniline, S-alkyl/aryl dithiocarbazates and thiosemicarbazide have been synthesized and characterized by... Four new Schiff bases of 1,10-phenanthroline-2,9-dicarboxaldehyde with sulfur-containing amines such as 2-mercaptoaniline, S-alkyl/aryl dithiocarbazates and thiosemicarbazide have been synthesized and characterized by spectroscopic and X-ray crystallographic techniques. A comparative study of the methods of synthesis has been made using both traditional and microwave techniques. A significant reduction in reaction time has been observed when the microwave method was used. In some of the reactions, the yields also increased significantly. 展开更多
关键词 PHENANTHROLINE SCHIFF Base Dithiocarbazide sulfur-containing Antibaterial
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QSPR Study on the Boiling Points of Some Oxygenand Sulfur-containing Organic Compounds 被引量:1
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作者 陈建挺 刘红玲 +2 位作者 王甫洋 于红霞 李定龙 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2009年第12期1561-1568,共8页
Structural and thermodynamic parameters of 56 oxygen-containing and 56 sulfur- containing organic compounds were computed at the B3LPY/6-311G** level using density functional theory (DFT) method. Furthermore,the d... Structural and thermodynamic parameters of 56 oxygen-containing and 56 sulfur- containing organic compounds were computed at the B3LPY/6-311G** level using density functional theory (DFT) method. Furthermore,the dependent equations between the experimental data of boiling points (Tb) and theoretical parameters were proposed with SPSS12.0 for windows software,whose correlation coefficients R2 are 0.933 and 0.945. These dependent equations were validated by cross-validation method (q2 are 0.923 and 0.929,respectively). VIF (variance inflation factors) and t-value methods were also used to verify the significance and self-correlationship of each variable. Results indicate that our dependent equation exhibits good prediction ability,and molecular polarizability (α) is the main factor affecting the Tb of oxygen- and sulfur-containing organic compounds. To our interest,obvious dependence could also be found among the oxygen- and sulfur-containing organic compounds' experimental data of boiling points (Tb) with R^2 of 0.857. 展开更多
关键词 boiling points oxygen-containing organic compounds sulfur-containing organic compounds quantitative structure-property relationship (QSPR) DFT
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Cis-and Trans-Coordination Assembly of Nitrogen Heterocycle with Copper(Ⅱ) and Silver(Ⅰ)
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作者 TAN Di TAN Gui-ping +3 位作者 HUANG Xiao-chun TONG Shan-ling YANG Ke-er YAN Yan 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2008年第6期661-667,共7页
After the preparation of 1,4-bis(4,5-dihydro-lH-imidazol-2-yl)benzene(bdib), a nitrogen heterocycle with potential coordination manners of both cis- and trans-configuration forms, three complexes, including cis-[... After the preparation of 1,4-bis(4,5-dihydro-lH-imidazol-2-yl)benzene(bdib), a nitrogen heterocycle with potential coordination manners of both cis- and trans-configuration forms, three complexes, including cis-[Cuz(bdib )2(/L-OCH3)2]Cl2·2MeOH(1), trans-[Cu(bdib)(AcO)2]n(2), and cis-[Ag2(bdib)2](NO3)2.2H20(3), were successfully self-assembled. Complexes 1 and 2 crystallized in the monoclinic system with P21/n space group and complex 3 in the triclinic system with P1 space group. 展开更多
关键词 Nitrogen heterocycle Cis- and trans-coordination COPPER SILVER
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Theoretical Design of High-spin Organic Molecules with —~*N—S— as a Spin-containing Fragment and Heterocycle as End Groups
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作者 WANG Li-min CHU De-qing +1 位作者 ZHANG Jing-ping WANG Rong-shun 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2006年第5期631-634,共4页
Novel stable high-spin molecules possessing three different arranging fashions were designed with —^*N—S— as a spin-containing (SC) fragment, an aromatic group, such as benzene ( 1 ), pyridine (2), pyridazi... Novel stable high-spin molecules possessing three different arranging fashions were designed with —^*N—S— as a spin-containing (SC) fragment, an aromatic group, such as benzene ( 1 ), pyridine (2), pyridazine (3) , pyrimidine (4), pyrazine (5) or triazine (6) as end groups (EG), and phenyl as a ferromagnetic coupling (FC) unit. The effects of different EG on the spin multiplicities of the ground states and their stabilities were investigated by means of the AM1-CI approach. All the investigated molecules corresponded to the FC and possessed high-spin ground states. The spin on the two atoms of the SC fragment was not in agreement with the delocalization results in the specific stability of —^*N—S—. In those molecules, the stabilities of the triplet states decreased when the distance between the atoms of central SC fragments (—N—) increased. The stabilities of the triplet states of compounds 1a-n, 1b-n and 1c-n, with heterocycles as EG were higher than those of the triplet states of those compounds with phenyl as EG. Furthermore, the stahilities of the triplet states of the compounds with pyrimidine and triazine as EG were higher than those with pyridine, pyridazine or pyrasine as EG. 展开更多
关键词 heterocycle End group BIRADICAL HIGH-SPIN AM1-CI
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Catalytic kinetics of dimethyl ether one-step synthesis over CeO_2–CaO–Pd/HZSM-5 catalyst in sulfur-containing syngas process 被引量:1
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作者 Ruizhi Chu Wenxin Hou +4 位作者 Xianliang Meng Tingting Xu Zhenyong Miao Guoguang Wu Lei Bai 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2016年第12期1735-1741,共7页
CeO_2–CaO–Pd/HZSM-5 catalyst was prepared for the dimethyl ether(DME) one-step synthesis in a continuous fixed-bed micro-reactor from the sulfur-containing syngas. The catalytic stability over hybrid catalyst of Ce... CeO_2–CaO–Pd/HZSM-5 catalyst was prepared for the dimethyl ether(DME) one-step synthesis in a continuous fixed-bed micro-reactor from the sulfur-containing syngas. The catalytic stability over hybrid catalyst of CeO_2–CaO–Pd/HZSM-5 was investigated to ensure that the kinetics experimental results were not significantly influenced by induction period and catalytic deactivation. A large number of kinetic data points(40 sets) were obtained over a range of temperature(240–300 °C), pressure(3–4 MPa), gas hourly space velocity(GHSV)(2000–3000 L·kg^(-1)·h^(-1)) and H_2/CO mole ratio(2–3). Kinetic model for the methanol synthesis reaction and the dehydration of methanol were obtained separately according to reaction mechanism and Langmuir–Hinshelwood mechanism. Regression parameters were investigated by the method combining the simplex method and Runge–Kutta method. The model calculations were in appropriate accordance with the experimental data. 展开更多
关键词 CeO_2–CaO –Pd/HZSM-5 catalyst DME One-step synthesis Catalytic kinetics sulfur-containing syngas
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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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Synthesis of 2-methoxy-6-oxo-1, 4, 2-diazaphosphorinane-2-oxide, A New Potential Antitumor Phosphorus Heterocycle Compound
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作者 Xu, L Zheng, GR +1 位作者 Xia, M Cai, JC 《Chinese Chemical Letters》 SCIE CAS CSCD 2000年第8期665-666,共2页
2-methoxy-6-oxo-1, 4, 2-diazaphosphorinane-2-oxide 8, phosphorus counterpart of 2, 6-dioxopiperazine, was synthesized as antitumor agent. The new phosphorus heterocycle compound 8 is the key intermediate in the synthe... 2-methoxy-6-oxo-1, 4, 2-diazaphosphorinane-2-oxide 8, phosphorus counterpart of 2, 6-dioxopiperazine, was synthesized as antitumor agent. The new phosphorus heterocycle compound 8 is the key intermediate in the synthesis of phosphorus counterpart of bisdioxopiperazine. 展开更多
关键词 antitumor activity phosphorus heterocycle compound 2 6-dioxopiperazine
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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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