Results 61 to 70 of about 40,209 (198)

Investigating the preparation of oxime derivatives of azacrown ethers containing piperidine-4-one heterocycles under microwave irradiation

Vietnam Journal of Science, Technology and Engineering
The use of multi-component reactions to simultaneously synthesise crown ethers and nitrogen-containing heterocycles is a synthetic approach that has attracted significant interest. With nitrogen heterocycles embedded in their structures, azacrown ethers
Tung H. To, Hieu D. Nguyen
doaj   +1 more source

Predicting Solid-State Heats of Formation of Newly Synthesized Polynitrogen Materials by Using Quantum Mechanical Calculations [PDF]

, 2008
We present density functional theory level predictions and analysis of the basic properties of newly synthesized high-nitrogen compounds together with 3,6-bis(2H-tetrazol-5-yl)-1,2,4,5-tetrazine (BTT) and 3,3′-azobis(6-amino-1,2,4,5-tetrazine) (DAAT ...
Abou-Rachid, H., Dudiy, S., Goddard, W. A., III, Hu, A., Song, Y., Zybin, S. V.   +5 more
core   +1 more source

Formal pyridine meta-azidation and its application for the synthesis of diazepines, ring-fused δ-carbolines and 1,2,3-triazolylpyridines

Nature Communications
The nitrogen atom serves as an important structural element in pharmacologic studies, highlighting the critical role of nitrogen-containing heterocycles in drug discovery.
Shu-Min Guo, Pengwei Xu, Constantin G. Daniliuc, Armido Studer   +3 more
doaj   +1 more source

Metal-free intermolecular formal cycloadditions enable an orthogonal access to nitrogen heterocycles

Nature Communications, 2016
Nitrogen containing heterocycles play key roles as both bioactive compounds and synthetic building blocks in organic chemistry. Here, the authors report the synthesis of a range of heterocyclic structures via metal free cycloadditions and provide ...
Lan-Gui Xie, Supaporn Niyomchon, Antonio J. Mota, Leticia González, Nuno Maulide   +4 more
doaj   +1 more source

Thioether-catalysed tandem synthesis of furans and cyclic ethers or lactones [PDF]

, 2017
Acyclic conjugated ynenediones tethered to an alcohol or carboxylic acid are converted into furanyl-substituted cyclic ethers or lactones in a single step by treatment with the tetrahydrothiophene.
Clark, J. Stephen, Klaus, Verena
core   +1 more source

Analysis and Evaluation of Volatile Chemical Components of Wild Ophiocordyceps sinensis and Its Mycelia in Xizang, China

Journal of Pharmacy and Bioallied Sciences
Background: As a rare traditional Chinese medicinal material, Ophiocordyceps sinensis is subject to counterfeiting in the market due to its limited distribution and insufficient supply and demand. Therefore, conducting research on its volatile components
Pei Qun, Zheng-Rong Lu, Jia-Yi Yang, Yan Liu, Zhan-Min Liu, Xuan-Wei Zhou   +5 more
doaj   +1 more source

Tuneable access to indole, indolone, and cinnoline derivatives from a common 1,4-diketone Michael acceptor

Beilstein Journal of Organic Chemistry, 2020
A convergent strategy is reported for the construction of nitrogen-containing heterocycles from common substrates: 1,4-diketones and primary amines.
Dalel El-Marrouki, Sabrina Touchet, Abderrahmen Abdelli, Hédi M’Rabet, Mohamed Lotfi Efrit, Philippe C. Gros   +5 more
doaj   +1 more source

Toward Charge-neutral ‘soft scorpionates’: Coordination Chemistry and Lewis Acid Promoted Isomerization of tris(1-organo-imidazol-2-ylthio)methanes [PDF]

, 2009
Two tris(1-organo-imidazol-2-ylthio)methanes, HC(S-timR)3 (R = organo = methyl, tert-butyl), have been prepared by a triphasic reaction between chloroform, the appropriate heterocycle, and saturated aqueous solutions of Na2CO3, in the presence of a phase
Gardinier, James R., Gwengo, Chengeto, Lindeman, Sergey V., Silva, Rosalice M., Smith, Mark D.   +4 more
core   +1 more source

Revisiting the structure and chemistry of 3(5)-Substituted Pyrazoles [PDF]

, 2019
Pyrazoles are known as versatile scaffolds in organic synthesis and medicinal chemistry, often used as starting materials for the preparation of more complex heterocyclic systems with relevance in the pharmaceutical field.
Alam, Alina Secrieru, Alkorta, Andes, Anwar, Behr, Brown, Castillo, Catalan, Chauhan, Clark, Elguero, Elnagdi, Favre, Fichez, Hall, Horta, Katritzky, Katritzky, Kost, Kumar, Larina, Maria Lurdes Santos Cristiano, Mert, Minkin, Minkin, Mohamed, Nagy, Nimbalkar, Paul Michael O’Neill, Schofield, Simons, Szajda, Taylor, Zerbi   +34 more
core   +2 more sources

Intramolecular Schmidt Reaction: Applications in Natural Product Synthesis

CHIMIA, 2006
The intramolecular Schmidt reaction was first described at the beginning of the 1990s and rapidly proved to be a powerful tool for the fast assembly of complex nitrogen-containing heterocycles.
Erich Nyfeler, Philippe Renaud
doaj   +1 more source