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Science China Chemistry 2023年第11期66卷 3148-3153页

作者： Jin-Huang Peng Yu-Qing Zheng Li-Gang Bai Wen-Bo Liu Hubei Key Lab on Organic and Polymeric Opto-Electronic Materials Engineering Research Center of Organosilicon Compounds&Materials(Ministry of Education)College of Chemistry and Molecular SciencesWuhan UniversityWuhan 430072China Wuhan University Shenzhen Research Institute Shenzhen 518000China

Construction of axially chiral 1-azafluorenes via nickel-catalyzed[2+2+2]cycloaddition of alkynes and(o-alkynyl)benzyl nitriles is described.This strategy enables enantioselective discrimination of two sterically similar ortho substituents,such as H and F,during the construction of tri-ortho-substituted biaryl atropisomers.Mechanistic studies including the stereochemistry model and the stability of the atropenantiomers toward racemization are provided.The unique steric hindrance provided by 1-azafluorene skeleton and the fine chiral cavity of the nickel catalyst are key to achieving high enantioselectivity.

关键词： asymmetric catalysis [2+2+2]cycloaddition nickel catalysis atropisomer heterocycle

Catalyst-Free Regio-and Diastereoselective Synthesis of Heterocyclic Nucleosides in the Eco-friendly Solvent 2-Methyltetrahydrofurant

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Chinese Journal of Chemistry 2023年第2期41卷 167-172页

作者： Xiaodong Gu Qingwei Du Weijian Song Jun(Joelle)Wang Department of Chemistry Hong Kong Baptist UniversityKowloonHong KongChina Department of Chemistry Southern University of Science and TechnologyShenzhenGuangdong 518055China

An efficient and practical synthesis of heterocyclic nucleosides is developed by a catalyst-free highly regioselective and diastereose-lective[3+2]annulation of a-purine-substituted acrylates with nitrones.The reaction operates with excellent functional group toler-ance,very mild reaction conditions,and with the green,sustainable,and eco-friendly 2-methyltetrahydrofuran(2-MeTHF)as sol-vent.Compared with other reactions of electron-deficient olefin dipolarophiles with nitrones,different regioselective cycloaddition products were observed in this work.This 1,3-dipolar cycloaddition reaction gives a series of isoxazolidinyl nucleosides in good to excellent yields with promising applications in biochemistry and medicinal chemistry.

关键词： heterocycle Nucleoside Catalyst-free Annulation Regioselectivity Synthetic methods Cycloaddition

The integration of dinitropyrazole and 1,3,4-oxadiazole:A novel hybrid heterocyclic skeleton for balancing energy and stability

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Defence Technology（防务技术） 2023年第6期24卷 122-128页

作者： Xiao-xiao Zheng Ting-ou Yan Lei Qian Hong-wei Yang Guang-bin Cheng School of Chemistry and Chemical Engineering Nanjing University of Science and TechnologyNanjing210094China

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.

关键词： heterocycle Azo-bridged Hybrid skeletons Energetic materials

Theoretical Design of High-spin Organic Molecules with —~* N—S— as a Spin-containing Fragment and heterocycle as End Groups

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Chemical Research in Chinese Universities 2006年第5期22卷 631-634页

作者： WANG Li-min CHU De-qing ZHANG Jing-ping WANG Rong-shun Faculty of Material and Chemical Engineering Tianfin Polytechnic University Tianjin 300160 P. R. China Faculty of Chemistry Northeast Normal University Changchun 130024 P. R. China

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.

关键词： heterocycle End group Biradical High-spin AM1-CI

Benzisoxazole core and benzoxazolopyrrolidine via HDDA-derived benzyne with PTIO/DMPO

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Chinese Chemical Letters 2023年第4期34卷 318-321页

作者： Yu Lei Wenjing Zhu Yajuan Zhang Qiong Hu Jie Dong Yimin Hu Key Laboratory of Functional Molecular Solids Ministry of EducationAnhui Laboratory of Molecule-Based MaterialsState Laboratory Cultivation BaseCollege of Chemistry and Materials ScienceAnhui Normal UniversityWuhu 241002China

A novel method for HDDA-derived benzyne trapped by nitrone was developed. This research described a simple and efficient pathway for the synthesis of benzisoxazoles from arynes and PTIO(2-phenyl-4,4,5,5-tetramethylimidazoline-3-oxide-1-oxyl), C-C and C-O bonds were formed in a single step without catalyst under mild conditions. The unexpected cleavage of C-N bond contributed to the formation of isoxazole ring, as indicated by DFT studies. Furthermore, we obtained the structure of benzoxazolopyrrolidine when the trapping agent is DMPO(5,5-dimethyl-1-pyrroline N-oxide).

关键词： Benzisoxazole HDDA reaction Benzyne Nitrone heterocycle

Clinical Use of COX-2 Inhibitors Containing Quinoline heterocycle as a Selective Therapeutic Agents for Complementary Medicine

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Clinical Complementary Medicine and Pharmacology 2023年第3期3卷 60-77页

作者： Megha P.Ambatkar Nilesh R.Rarokar Pramod B.Khedekar Department of Pharmaceutical Sciences Rashtrasant Tukadoji Maharaj Nagpur UniversityNagpurMaharashtra 440033India

Inflammation represents an initial response of immune system and is involved in a number of biochemical inci-dents.Such incidents may multiply and further develop the provocative response.Over the past 15 years,various classes of secondary metabolites that were isolated from plant and marine sources have been described as natural cyclooxygenase(COX)inhibitors.The majority of natural COX inhibitors could be used as a selective therapeutic agent for complementary medicine and clinical applications.Currently,the inflammation is commonly treated by non-steroidal anti-inflammatory drugs(NSAIDs),several medications of which,however,have been linked to renal and gastrointestinal side effects.A variety of inhibitors of COX-2 that are selective(celecoxib,rofecoxib,valdecoxib and others)have been designed as NSAIDs mostly with enhanced stomach safety profiles.This helps to improve the compliance and functions in the geriatric patients as they have so many complications and problems associated with the diseases.The use of complementary medicine in combination with clinical therapy might give better results than medicine alone.Some disease condition like cancer which shows the COX-2 expressions could also have treatment related problems in such cases the selective inhibitors used as a complementary medicine.On the other hand,elevated cardiovascular risks have brought increasing worries about the safety of using specific inhibitors of COX-2.This current review focuses on how quinoline heterocycle was used for creation of inhibitors of COX-2 since 2009 along with its clinical significance in complementary medicine.These agents included the variety of substituents on the ring or ring attached to other heterocycles.As a result,the quinoline heterocycle will be used for creating and finding anti-inflammatory COX-2 medicines.

关键词： Quinoline heterocycle Inflammation Cyclooxygenase Natural Complementary NSAID COX-2 inhibitor

Synthesis and cytotoxic activity of heterocycle-substituted phthalimide derivatives

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Chinese Chemical Letters 2010年第8期21卷 902-904页

作者： Ya Jun Yang Ya Nan Yang Jian Shuang Jiang Zi Ming Feng Hong Yan Liu Xian Dao Pan Pei Cheng Zhang Key Laboratory of Bioactive Substances and Resources Utilization of Chinese Herbal Medicine(Ministry of Education) Institute of Materia MedicaPeking Union Medical College and Chinese Academy of Medical SciencesBeijing 100050China Beijing Union Pharmaceutical Factory Beijing 102600China

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.

关键词： Phthalimide heterocycle α-Bromoketone Cytotoxic activity

RELATIONSHIPS BETWEEN STRUCTURE AND EFFECT OF IODIUM heterocycle COMPOUNDS ON TUMOR CELLS DNA, RNA AND PROTEIN SYNTHESES in vitro

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Chinese Science Bulletin 1989年第18期34卷 1559-1562页

作者：郑荣梁刘力生顾继杰葛祥斌张龙弟侯自杰 Departments of Biology and Chemistry Lanzhou University

I. INTRODUCTION The obvious relationships between the structure and the protection against ionizing radiation by the transfer of energy of iodium heterocycle compounds have been found by us. The hypotensive response a... 详细信息

关键词： iodium heterocycle compound tumor cells DNA RNA protein

Structural optimization and biological evaluation of 1,5-disubstituted pyrazole-3-carboxamines as potent inhibitors of human 5-lipoxygenase

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Acta Pharmaceutica Sinica B 2016年第1期6卷 32-45页

作者： Yu Zhou Jun Liu Mingyue Zheng Shuli Zheng Chunyi Jiang Xiaomei Zhou Dong Zhang Jihui Zhao Deju Ye Mingfang Zheng Hualiang Jiang Dongxiang Liu Jian Cheng Hong Liu CAS Key Laboratory of Receptor Research Shanghai Institute of Materia MedicaChinese Academy of Sciences China Pharmaceutical University Jiangsu Key Laboratory of Translational Research and Therapy for Neuro-Psycho-Diseases and Institute of Neuroscience Soochow University

Human 5-lipoxygenase(5-LOX)is a well-validated drug target and its inhibitors are potential drugs for treating leukotriene-related disorders.Our previous work on structural optimization of the hit compound 2 from our in-house collection identified two lead compounds,3a and 3b,exhibiting a potent inhibitory profile against 5-LOX with IC_(50) values less than 1 mmol/L in cell-based assays.Here,we further optimized these compounds to prepare a class of novel pyrazole derivatives by opening the fusedring system.Several new compounds exhibited more potent inhibitory activity than the lead compounds against 5-LOX.In particular,compound 4e not only suppressed lipopolysaccharide-induced inflammation in brain inflammatory cells and protected neurons from oxidative toxicity,but also significantly decreased infarct damage in a mouse model of cerebral ischemia.Molecular docking analysis further confirmed the consistency of our theoretical results and experimental data.In conclusion,the excellent in vitro andin vivo inhibitory activities of these compounds against 5-LOX suggested that these novel chemical structures have a promising therapeutic potential to treat leukotriene-related disorders.

关键词： 5-Lipoxygenase 5-LOX inhibitors Pyrazole derivatives Leukotrienes-related diseases In vivo Benzo-fused heterocycle Ischemic incults Brain inflammation

An Environmentally Benign Catalytic Method for Versatile Synthesis of 1,4-Dihydropyridines via Multicomponent Reactions

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中国化学:英文版 2015年第5期33卷 568-572页

作者： Shuo Cao Shanshan Zhong Changfeng Hu Jie-Ping Wan Chengping Wen Key Laboratory of Functional Small Organic Molecule Ministry of EducationCollege of Chemistry and Chemical EngineeringJiangxi Normal UniversityNanchangJiangxi 330022China College of Basic Medical Sciences Zhejiang Chinese Medical UniversityHangzhouZhejiang 310053China

The synthesis of diverse 1,4-dihydropyridines have been achieved via the multicomponent reactions of aldehydes,enaminones and amines.The reactions have been smoothly performed in water to provide all products with mod... 详细信息

关键词： lactic acid catalysis multicomponent reactions 1 4-dihydropyridines green catalysis heterocycle