نتایج جستجو برای: heterocycles

تعداد نتایج: 2986  

Journal: :Molecules 2011
Yahia Nasser Mabkhot Abdullah Mohammed Al-Majid Assem Barakat Saeed Alshahrani Yamin Siddiqui

A series of new bis(heterocycles) featuring thieno[2,3-b]thiophene rings was synthesized in a combinatorial manner. Intramolecular cyclization of enaminone derivatives with appropriate N-nucleophiles afforded the target compounds. All compounds were characterized by ¹H-, ¹³C-NMR, GCMS, IR, and UV-Vis spectrometry. These compounds represent a new class of sulfur- and nitrogen-containing heterocy...

Journal: :Molecules 2017
Bruno Commare Etienne Schmitt Fallia Aribi Armen Panossian Jean-Pierre Vors Sergiy Pazenok Frédéric R Leroux

Fluorinated heterocycles are important building blocks in pharmaceutical, agrochemical and material sciences. Therefore, organofluorine chemistry has witnessed high interest in the development of efficient methods for the introduction of emergent fluorinated substituents (EFS) onto heterocycles. In this context, fluoroalkyl amino reagents (FARs)-a class of chemicals that was slightly forgotten ...

2017
Jacob Davies Nadeem S Sheikh Daniele Leonori

Shown herein is that polyfunctionalized nitrogen heterocycles can be easily prepared by a visible-light-mediated radical cascade process. This divergent strategy features the oxidative generation of iminyl radicals and subsequent cyclization/radical trapping, which allows the effective construction of highly functionalized heterocycles. The reactions proceed efficiently at room temperature, uti...

2011
Douglas C. Behenna Yiyang Liu Taiga Yurino Jimin Kim David E. White Scott C. Virgil Brian M. Stoltz

The enantioselective synthesis of nitrogen-containing heterocycles (N-heterocycles) represents a substantial chemical research effort and resonates across numerous disciplines, including the total synthesis of natural products and medicinal chemistry. In this Article, we describe the highly enantioselective palladium-catalysed decarboxylative allylic alkylation of readily available lactams to f...

2015
Chao Wu Peng Cao

The asymmetric unit of the polymeric title compound, [Ni(C8H4O4)(C10H14N4)(H2O)] n , contains one Ni(2+) cation, one coordinating water mol-ecule, one 3,3',5,5'-tetra-methyl-4,4'-bi-pyrazole ligand and half each of two benzene-1,4-di-carboxyl-ate anions, the other halves being generated by inversion symmetry. The Ni(2+) cation exhibits an octa-hedral N2O4 coordination sphere defined by the O at...

Journal: :Chemical Reviews 2004

Journal: :Heterocycles 2023

Journal: :Molecules 2007
Dinesh Ramesh Garud Mamoru Koketsu Hideharu Ishihara

Selenium-containing heterocyclic compounds have been well recognized, not only because of their remarkable reactivities and chemical properties, but also because of their diverse pharmaceutical applications. In this context, isoselenocyanates have been emerged as a powerful tool for the synthesis of selenium-containing heterocycles, since they are easy to prepare and store and are safe to handl...

2017
Layal Hariss Kamal Bou Hadir Mirvat El-Masri Thierry Roisnel René Grée Ali Hachem

Using an aerobic oxidative coupling, different new imidazo[1,2-a]-N-heterocycles with gem-difluroroalkyl side chains have been prepared in fair yields by the reaction of gem-difluoroenones with aminopyridines, -pyrimidines and -pyridazines. Condensed heterocycles of this type play an important role as key core structures of various bioactive compounds. Further, starting with a chloroimidazopyri...

2017
Marko Kljajic Johannes G Puschnig Hansjörg Weber Rolf Breinbauer

An additive-free Pd-catalyzed α-allylation of different imino-group-ontaining heterocycles is reported. The activation of α-CH pronucleophiles (pKa (DMSO) > 25) occurs without the addition of strong bases or Lewis acids using only the Pd/Xantphos catalyst system. The reaction scope has been studied for various 5- and 6-membered nitrogen-containing heterocycles (yields up to 96%). Mechanistic in...

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