Results 81 to 90 of about 24,842 (217)

Synthesis of 1,4-naphthoquinone derivatives using 1,3-dipolar cycloaddition and Sonogashira reactions

Orbital: The Electronic Journal of Chemistry, 2010
Naphthoquinones are known according to their important bio-activities, such as their antitumoral and topoisomerase inhibition properties. From 2-azido (3) or 2,3-diacetylene-1,4-naphthoquinone (4) it was possible to obtain triazole derivatives ...
Wilson Silva do Nascimento, Mauro Gomes da Silva, Ronaldo Nascimento de Oliveira, Celso Amorim Câmara   +3 more
doaj  

New Quinazolin-4(3H)-One Derivatives Incorporating Isoxazole Moiety as Antioxidant Agents: Synthesis, Structural Characterization, and Theoretical DFT Mechanistic Study

Pharmaceuticals
Background: This research centers on the development and spectroscopic characterization of new quinazolin-4(3H)-one-isoxazole derivatives (5a–e). The aim was to investigate the regioselectivity of the 1,3-dipolar cycloaddition involving arylnitriloxides ...
Yassine Rhazi, Riham Sghyar, Noemi Deak, Bouchra Es-Sounni, Bouchra Rossafi, Albert Soran, Mustapha Laghmari, Azize Arzine, Asmae Nakkabi, Khalil Hammani, Samir Chtita, Mohammed M. Alanazi, Gabriela Nemes, Mohamed El. Yazidi   +13 more
doaj   +1 more source

The Genuine Carbene Conundrum

Chemistry – A European Journal, EarlyView.
From fleeting intermediates to well‐defined molecular structures, carbenes (neutral divalent carbon) remind us that the most reactive ideas often make a large impact. Despite their wide‐ranging applications, the direct characterization of these reactive species remains a persistent experimental challenge.
Bethany Sawyer, Jesse. L. Peltier, Rodolphe Jazzar   +2 more
wiley   +1 more source

The Role of Five‐Membered Aromatic Rings Containing N and O in Modulating Bile Acid Receptors: An Overview

ChemMedChem, Accepted Article.
Over the past decades extensive scientific research in the fields of chemistry and pharmaceutical chemistry has led to the synthesis and study of numerous chemical compounds with diverse therapeutic applications. Many of these compounds feature heterocyclic aromatic structures, including six‐, five‐, and four‐membered rings.
Claudia Finamore, Carmen Festa, Rosa Barbato, Stefano Fiorucci, Angela Zampella, Simona De Marino   +5 more
wiley   +1 more source

1,3-Dipolar cycloaddition reactivities of perfluorinated aryl azides with enamines and strained dipolarophiles.

Journal of the American Chemical Society, 2015
The reactivities of enamines and predistorted (strained) dipolarophiles toward perfluoroaryl azides (PFAAs) were explored experimentally and computationally. Kinetic analyses indicate that PFAAs undergo (3 + 2) cycloadditions with enamines up to 4 orders
Sheng Xie, Steven A. Lopez, O. Ramström, Mingdi Yan, K. Houk   +4 more
semanticscholar   +1 more source

Enantiomerically Enriched Aziridine‐2‐carboxylates via Copper‐Catalyzed Reductive Kinetic Resolution of 2H‐Azirines

Angewandte Chemie, Volume 137, Issue 26, June 24, 2025.
Kinetic resolution by copper hydride catalyzed reduction of 2H‐azirines secured optically enriched N‐H aziridine‐2‐carboxylates with excellent diastereoselectivity (>20:1) and good enantioselectivity (up to 94% ee). DFT calculations and non‐covalent interaction analysis established the reaction pathway and revealed two key non‐covalent interactions ...
Yinuo Zheng, Elvis Wang Hei Ng, Antonio Rizzo, Pauline Chiu   +3 more
wiley   +2 more sources

A Diastereoselective Synthesis of Dispiro[oxindole-cyclohexanone]pyrrolidines by 1,3-Dipolar Cycloaddition

Molecules, 2017
For the first time, arylmethylidene cyclohexanones that are non-symmetrical due to the presence of peripheral substituents were studied in 1,3-dipolar cycloaddition reactions.
Alexander Anis’kov, Irina Klochkova, Roman Tumskiy, Alevtina Yegorova   +3 more
doaj   +1 more source

Double Click for Chirality: Chiral Dibenzo‐cycloocta‐bis‐triazoles via Strain‐Promoted Alkyne‐Azide Cycloaddition

ChemPhotoChem, EarlyView.
Strain‐promoted, double alkyne‐azide 1,3‐dipolar cycloadditions make dibenzo‐cycloocta‐bis‐triazoles which display a form of chirality that to date has been overlooked. The enantiomers can be resolved, with their remarkably high configurational stability being exemplified through a chiral fluorescent example.
Sebastian Pim, Aaron D. G. Campbell, Dmitry Levshov, Wouter Herrebout, Gonzalo Durán‐Sampedro, Michael J. Hall, Roly J. Armstrong, Donal F. O'Shea   +7 more
wiley   +1 more source

Highly Efficient and Diastereoselective Synthesis of New Pyrazolylpyrrolizine and Pyrazolylpyrrolidine Derivates by a Three-Component Domino Process

Molecules, 2014
Diastereoselective reactions between 4-formylpyrazoles, N-substituted maleimides and glycine derivates led to new series of pyrazolyldipyrrolo [3,4-a:3',4'-f]pyrrolizines and pyrazolylpyrrolo[3,4-c]pyrroles in good yields.
Jairo Quiroga, Jaime Gálvez, Rodrigo Abonia, Braulio Insuasty, Alejandro Ortíz, Justo Cobo, Manuel Nogueras   +6 more
doaj   +1 more source

Novel 3H ‐1,2,3‐Dithiaphosphole and Unprecedented 1,3,2,4‐Dithiadiphosphinane Heterocycles: Unanticipated Cyclization Reactions of Lawesson's Reagent and Alkynes

European Journal of Organic Chemistry, Accepted Article.
Treatment of Lawesson's reagent with selected alkyl or aryl alkynes results in the formation of cyclization products such as 3H‐1,2,3‐dithiaphosphole‐3‐sulfide or unprecedented 1,3,2,4dithiadiphosphinane‐2,4‐disulfide derivatives. The new heterocycles are characterized spectroscopically and in two cases by crystal structure analyses. Density functional
Felix Blüm, Bernd Goldfuss, Holger Butenschön   +2 more
wiley   +1 more source