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Chinese Chemical Letters 2021年第1期32卷 393-396页

作者： Yuan Zhang Han Luo Qixing Lu Qiaoyu An You Li Shanshan Li Zongyuan Tang Baosheng Li School of Chemistry and Chemical Engineering Chongqing UniversityChongqing 400030China

We studied the cascade nucleophilic addition reactions of 1,2,3-triazines with activated acetonitriles or ketones,which were used to construct highly substituted pyridines that are not easily accessed by conventional *** strategy addressed some structural diversity issues currently facing medicinal chemistry,and the resulting pyridines could be used as convenient precursors for the synthesis of related *** particular,our method was applied to the syntheses of the marketed drug etoricoxib and several biologically important molecules in a few steps.

关键词： 1,2,3-Triazines pyridines Nucleophilic addition Divergent synthesis Pharmaceuticals synthesis

Direct benzylic functionalization of pyridines:Palladium-catalyzed mono-α-arylation of α-(2-pyridinyl)acetates with heteroaryl halides

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Chinese Chemical Letters 2020年第1期31卷 91-94页

作者： Chaochao Jin Kun Xu Xiao Fan Changyao Liu Jiajing Tan Department of Organic Chemistry College of ChemistryBeijing Advanced Innovation Center for Soft Matter Science and EngineeringBeijing University of Chemical TechnologyBeijing 100029China College of Chemistry and Pharmaceutical Engineering Nanyang Normal UniversityNanyang 473061China School of Food and Chemical Engineering Beijing Technology and Business UniversityBeijing 100048China

Herein,we report a Pd-catalyzed mono-a-arylation reaction for pyridine benzylic *** approach serves as an efficient alternative to synthesize di-heteroaryl acetates in good yields and ***,the method is applicable to heteroa ryl substrate combinations,and exhibits great functional group tolerance.A streamlined protocol also enables the rapid synthesis of diheteroaryl *** synthetic value was also demonstrated by scale-up experiments.

关键词： α-Arylation Palladium Heterocycles pyridines Cross-coupling

Iodomethane as an organocatalyst for the aerobic ortho-selective trifluoromethylation of pyridines

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Science China Chemistry 2023年第1期66卷 133-138页

作者： Jianjin Yu Renqin Zhan Chao-Jun Li Huiying Zeng State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical EngineeringLanzhou University.Lanzhou 730000China Department of Chemistry FQRNT Centre for Green Chemistry and CatalysisMcGll UniversityMontrealOuebec H3A OB8Canada

Iodomethane is usually used as an electrophilic methylation ***,we report its use as a C1 organocatalyst for the aerobic ortho-selective trifluoromethylation of pyridines in the absence of a transition *** acid(TFA)was employed as an inexpensive,readily available trifluoromethyl *** reaction efficiently produced a variety of trifluoromethylation products,with good functional group ***-containing drug molecules could also be selectively trifluoromethylated for late-stage *** studies showed that iodomethane selectively reacted with the pyridine starting material,rather than the pyridine product,to generate the corresponding N-methylpyridinium *** decarboxylation of trifluoroacetic acid produced a trifluoromethyl anion,which added to the methylpyridinium iodide,and the subsequent aerobic rearomatization led to the generation of the ortho-trifluoromethylated product.

关键词： iodomethane-catalysis trifluoromethylation pyridines transition-metal-free trifluoroacetic acid

One-Pot Synthesis of Hantzsch pyridines via NH4I Promoted Condensation of 1,3-Dicarbonyl Compounds with DMSO and NH4OAc

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Chinese Journal of Chemistry 2016年第9期34卷 887-894页

作者： Liming Chang Junyi Lai Gaoqing Yuan School of Chemistry and Chemical Engineering South China University of Technology Guangzhou Guangdong 510640 China

A one-pot synthesis of Hantzsch pyridines was achieved through NH4I-promoted condensation of 1,3-dicarbonyl compounds with DMSO and NH4OAc, in which the C4 of the pyridine rings was derived from DMSO and the nitrogen ... 详细信息

关键词： pyridines 1,3-dicarbonyl compounds dimethyl sulfoxide ammonium iodide

<i>β</i>-Oxoanilides in Heterocyclic Synthesis: Synthesis and Antimicrobial Activity of pyridines, Pyrans, Pyrimidines and Azolo, Azinopyrimidines Incorporating Antipyrine Moiety

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International Journal of Organic Chemistry 2012年第4期2卷 341-351页

作者： Abdel Haleem M. Hussein Mohamed A. M. Gad-Elkareem Abu-Bakr A. A. M. El-Adasy Ahmed A. Khames Ismail M. M. Othman Department of Chemistry Faculty of Science Al-Azhar University Assiut Egypt

Condensation of β-Oxoanilide 1 with active methylene derivatives 2a,bafforded the pyridine derivative 5, and with crotononitrile afforded the pyridine 8. Compounds 9 and 11a-c were obtained by reaction of 1 with malononitrile dimer and arylidinemalononitrile 10a-10c. In contrast, when compound 1 reacted with ethoxymethylen malononitrile afforded the pyridine derivative 13. On the other hand, treatment of 1 with anthranilic acid gave the quinoline derivative 14. Also, reactions of 1 with isothiocyanate derivatives afforded compounds 16-18. The reaction of 1 with chalcone derivative afforded the pyridine derivative 22. Treatment of compound 1 with thiourea produced pyrimidine derivative 23. Furthermore, compound 1 converted into pyrimidinethione 24a and pyrimidinone 24b on treatment with a mixture of aromatic aldehydes and thiourea or urea respectively. Reaction of 24a with hydrazonyl halide, thiosemicarbazide and arylidinecyanothioacetamide afforded compounds 26, 28 and 29. Compound 29 was treated with chloroacetonitrile to afford compound 30. Six compounds from the newly synthesized were screened for antibacterial and antifungal activity against bacteria staphylococcus aureus, bacillus cereus and klebsiella pneumonia and fungi aspergillus flavus and aspergillus ochraceous, respectively. Some of the tested compounds showed significant antimicrobial activity. IR, 1H NMR, mass spectral data, and elemental analysis elucidated the structures of all the newly synthesized compounds.

关键词： β-Oxoanilides pyridines Pyrans Pyrimidines Azolo Azinopyrimidines

Palladium-Catalyzed Heck-Type Reaction of Oximes with Allylic Alcohols: Synthesis of pyridines

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Palladium-Catalyzed Heck-Type Reaction of Oximes with Allyli...

Direct photolysis of N-methoxypyridiniums for the pyridylation of carbon/heteroatom-hydrogen bonds

中国化学会全国第十二届有机合成化学学术研讨会

作者： Zheng,Mei-Fang Jiang,Huan-Feng School of Chemistry and Chemical Engineering South China Univertsity of Technology

pyridines are ubiquitous in many bioactive natural products,organic conducting materials,and pharmaceutical compounds. Although there are many synthetic methods for the construction of pyridines,most of them suffer from several *** development of efficient and practical procedures that maximize step economy with easily accessible starting materials to construct these valuable skeletons remains highly ***,we describe a palladium-catalyzed Heck-type reaction of oximes and allylic alcohols to afford different substituted pyridines with efficient *** mild reaction conditions,simple reaction system and readily functionalized products make the present protocol very attractive,which can be directly used to functionalized material synthesis.

关键词： pyridines Heck palladium allylic alcohols

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Science China Chemistry 2022年第12期65卷 2494-2499页

作者： He Sheng Bei-Bei Zhang Qiang Liu Zhu-Sheng Yang Zhi-Xiang Wang Xiang-Yu Chen School of Materials and Architectural Engineering Guizhou Normal UniversityGuiyang550025China School of Chemical Sciences University of the Chinese Academy of SciencesBeijing100049China

Current synthetic methods for the functionalization of pyridinium salts usually rely on transition metals,oxidants and/or *** date,no direct photolysis method exists under photocatalyst-,transition metal-and oxidant-free *** herein demonstrate the first direct photolysis of N-methoxypyridinium salts for the selective assembly of various pyridines by using a series of common feedstocks,including amine-boranes,unactivated alkanes,phosphine oxides,amides,silanes and aldehydes.

关键词： photolysis N-methoxypyridiniums hydrogen atom transfer pyridines

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Facile and Rapid Access to Poly Functionalized Pyridine Derivatives

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Chinese Journal of Chemistry 2011年第5期29卷 1049-1054页

作者： Shinde Pravin V. Shingate Bapurao B. Shingare Murlidhar S. Department of Chemistry Dr. Babasaheb Ambedkar Marathwada University Aurangabad-431004 India

An efficient and greener protocol for the synthesis of poly functionalized pyridines using tetra-n-butyl ammonium fluoride （TBAF） in water is established. Remarkable advantages of the present synthetic strategy over the others are shorter reaction times, higher isolated yields, reuse of catalytic system, simple work-up procedure and more especially its applicability to heteryl and aliphatic aldehydes.

关键词： green chemistry pyridines tetra-n-butyl ammonium fluoride (TBAF) water chemistry

Stress kinase inhibition modulates acute experimental pancreatitis

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World Journal of Gastroenterology 2001年第2期7卷 259-265页

作者： F.Fleischer R.Dabew B.Goke ACC Wagner Department of Gastroenterology InselspitalUniversity of BernSwitzerland

AIM: To examine the role of p38 during acute experimental cerulein pancreatitis. METHODS: Rats were treated with cerulein with or without a specific JNK inhibitor (CEP1347) and/or a specific p38 inhibitor (SB203580) and pancreatic stress kinase activity was determined. Parameters to assess pancreatitis included trypsin, amylase, lipase, pancreatic weight and histology. RESULTS: JNK inhibition with CEP1347 ameliorated pancreatitis, reducing pancreatic edema. In contrast, p38 inhibition with SB203580 aggravated pancreatitis with higher trypsin levels and, with induction of acinar necrosis not normally found after cerulein hyperstimulation. Simultaneous treatment with both CEP1347 and SB203580 mutually abolished the effects of either compound on cerulein pancreatitis. CONCLUSION: Stress kinases modulate pancreatitis differentially. JNK seems to promote pancreatitis development, possibly by supporting inflammatory reactions such as edema formation while its inhibition ameliorates pancreatitis. In contrast, p38 may help reduce organ destruction while inhibition of p38 during induction of cerulein pancreatitis leads to the occurrence of acinar necrosis.

关键词： Acute Disease Animals Caerulein Carbazoles Enzyme Inhibitors Imidazoles Indoles Mitogen-Activated Protein Kinases inhibitors Models, Animal Necrosis Pancreatitis pyridines Rats Trypsin p38 Mitogen-Activated Protein Kinases

Interleukin-1 beta up-regulates tissue inhibitor of matrix metalloproteinase-1 mRNA and phosphorylation of c-jun N-terminal kinase and p38 in hepatic stellate cells

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World Journal of Gastroenterology 2006年第9期12卷 1392-1396页

作者： Ya-Ping Zhang Xi-Xian Yao Xia Zhao Department of Gastroenterology the Second Hospital of Hebei Medical University Shijiazhuang 050000 Hebei Province China

AIM： To study the relationship between interleukin-lbeta （IL-1β） up-regulating tissue inhibitor of matrix metalloproteinase-1 （TIMMP-1） mRNA expression and phosphorylation of both c-jun N-terminal kinase （INK） and p38 in rat heffatic stellate cells （HSC）. METHODS： RT-PCR was performed to measure the expression of TIMMP-1 mRNA in rat HSC. Western blot was performed to measure IL-1β-induced JNK and p38 activities in rat HSC. RESULTS： TIMMP-1 mRNA expression （1.191± 0.079） was much higher after treatment with IL-1β （10 ng/mL） for 24 h than in control group （0.545±0.091）（P〈0.01）. IL-1β activated INK and p38 in a time-dependent manner. After stimulation with IL-1β for 0, 5, 15, 30, 60 and 120 min, the INK activity was 0.982±0.299, 1.501±0.720, 2.133±0.882, 3.360±0.452, 2.181±0.789, and 1.385 ± 0.368, respectively. There was a significant difference in JNK activity at 15 min （P〈 0.01）, 30 min （P〈 0.01） and 60 min （P〈0.01） in comparison to that at 0 min. The p38 activity was 1.061±0.310, 2.050±0.863, 2.380±0.573, 2.973±0.953, 2.421±0.793, and 1.755 ± 0.433 at the 6 time points （0, 5, 15, 30, 60 and 120 min） respectively. There was a significant difference in p38 activity at 5 min （P〈0.05）, 15 min （P〈0.01）, 30 min （P〈0.01） and 60 min （P〈0.01） compared to that at 0 min. TIMMP-1 mRNA expression trended to decrease in 3 groups pretreated with different concentrations of SP600125 （10 μmol/L, 1.022±0.113; 20 μmol/L, 0.869±0.070; 40 μmol/L, 0.666±0.123）. Their decreases were all significant （P〈0.05, P〈0.01, P〈0.01） in comparison to control group （without SP600125 treatment, 1.163±0.107）. In the other 3 groups pretreated with different concentrations of SB203580 （10 μmol/L, 1.507±0.099; 20 μmol/L, 1.698±0.107; 40 μmol/L, 1.857±0.054）, the expression of TIMMP-1 mRNA increased. Their levels were higher than those in the control group （without SB203580 treatment, 1.027 ± 0.061） with a significant statistical significance （P〈 0.01）. CONCLUSION： IL-1β has a direct action on hepati

关键词： Up-Regulation Animals Anthracenes Blotting, Western Cell Line Enzyme Inhibitors Imidazoles Interleukin-1 JNK Mitogen-Activated Protein Kinases Liver Liver Cirrhosis Phosphorylation pyridines RNA, Messenger Rats Reverse Transcriptase Polymerase Chain Reaction Signal Transduction Time Factors Tissue Inhibitor of Metalloproteinase-1 p38 Mitogen-Activated Protein Kinases