Results 61 to 70 of about 24,842 (217)

Mechanochemical Strategies Applied to the Late‐Stage Modifications of Pharmaceutically Active Compounds

Angewandte Chemie International Edition, Accepted Article.
This review explores the potential of mechanochemistry in the late‐stage modification of active pharmaceutical ingredients (APIs), offering a comprehensive analysis of methods designed to transform structurally complex molecular scaffolds. By examining the scope, efficiency, and mechanistic aspects of these approaches, the review highlights protocols ...
Johanna Templ, Lars Borchardt
wiley   +1 more source

Metal-catalyzed 1,3-dipolar cycloaddition reactions of nitrile oxides.

Organic and biomolecular chemistry, 2018
In the present review advances in the metal-catalyzed 1,3-dipolar cycloaddition reactions of nitrile oxides, mainly in the last decade, will be presented and discussed. An overview on the structure, preparation, dimerization and related reactions as well
Silvia Roscales, J. Plumet
semanticscholar   +1 more source

1,3-Dipolar cycloaddition of diazomethane with a chiral azlactone

Tetrahedron Letters, 1994
AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
Cativiela, Carlos, Díaz de Villegas, María D., Jiménez, Ana I., Lahoz, Fernando J.   +3 more
openaire   +4 more sources

Microwave-Assisted Synthesis of Fluorescent Pyrido[2,3-b]indolizines from Alkylpyridinium Salts and Enaminones

Molecules, 2020
Pyridinium ylides are well recognized as dipoles for cycloaddition reactions. In its turn, the microwave-assisted interaction of N-(cyanomethyl)-2-alkylpyridinium salts with enaminones unexpectedly proceeds as a domino sequence of cycloisomerization and ...
Ekaterina A. Sokolova, Alexey A. Festa, Karthikeyan Subramani, Victor B. Rybakov, Alexey V. Varlamov, Leonid G. Voskressensky, Erik V. Van der Eycken   +6 more
doaj   +1 more source

Reactivity of Pnictaalumenes Towards 1,3‐Dipole Molecules

Angewandte Chemie International Edition, EarlyView.
Pnictaalumenes with a Pn═Al multiple bonds undergo azide or diazoalkene insertions rather than [3+2] cycloadditions. This results in AlN2P heterocycles, which show a great structural variety depending on the sterics of the azide. With TMS‐diazoalkane, thermal rearrangements afford rare cyanidoaluminates. Abstract Alkynes undergo 1,3‐dipolar cyclization
Tim Wellnitz, Edgar Zander, Leonie Wüst, Jakob Boardman, Max Neubauer, Samuel Nees, Holger Braunschweig, Christian Hering‐Junghans   +7 more
wiley   +1 more source

Intermolecular 1,3-dipolar cycloadditions of azomethine imines [PDF]

Arkivoc, 2006
Dipolar cycloadditions of azomethine imines, formed in situ from aldehydes and N1-alkyl-N2-acylhydrazines, with electron-deficient dipolarophiles produce pyrazolidines: mono-substituted dipolarophiles afford principally 4-substituted pyrazolidines.
Jones, Raymond C.F., Hollis, Stephen J., Iley, James N.   +2 more
openaire   +4 more sources

Decarboxylation-Driven Double Annulations: Innovative Multi-Component Reaction Pathways

Molecules
A concerted five-component reaction strategy has been developed, featuring double [3+2] cycloadditions utilizing aspartic acid. This approach provides valuable insights into mechanistic pathways, allowing for the distinction between concerted and ...
Desheng Zhan, Gang Yang, Tieli Zhou, Sashirekha Nallapati, Xiaofeng Zhang   +4 more
doaj   +1 more source

A porphyrin-centred fullerene tetramer containing an N@C60 substituent [PDF]

Royal Society Open Science, 2018
An N@C60-containing C60 tetramer was synthesized by quadruple 1,3-dipolar cycloaddition (Prato) reaction. This molecule demonstrates the N@C60 qubit's ability to form covalently linked arrays.
Harry Macpherson, Stuart Cornes, Shen Zhou, Kyriakos Porfyrakis   +3 more
doaj   +1 more source

Tunable Endo/Exo Selectivity in Direct Catalytic Asymmetric 1,3‐Dipolar Cycloadditions with Polyfunctional Lewis Acid / Azolium‐Aryloxide Catalysts

Angewandte Chemie International Edition, Accepted Article.
Catalytic asymmetric 1,3‐dipolar cycloadditions (1,3‐DCA) using iminoesters as ylide precursors offer a powerful approach to accessing stereochemically complex, biologically relevant pyrrolidines. While previous studies have already achieved impressive stereoselectivities, catalytic productivity remains a challenge, with turnover numbers (TON ...
Adrian Bürstner, Patrick Becker, Alexander Allgaier, Lucca Pfitzer, Daniel Wanner, Johanna Dollinger, Felix Willig, Justin Herrmann, Vukoslava Miskov-Pajic, Andreas Hans, Wolfgang Frey, Joris van Slageren, Johannes Kästner, René Peters   +13 more
wiley   +1 more source

The hexameric resorcinarene capsule as an artificial enzyme: ruling the regio and stereochemistry of a 1,3-dipolar cycloaddition between nitrones and unsaturated aldehydes

, 2018
When a 1,3-dipolar cycloaddition between nitrones and α,β-unsaturated aldehydes catalyzed by L-proline derivatives takes place inside the hexameric resorcin[4]arene capsule the products are obtained in higher yields and selectivity, with respect to the ...
Pellegrino La Manna, M. D. Rosa, Carmen Talotta, C. Gaeta, A. Soriente, Giuseppe Floresta, A. Rescifina, P. Neri   +7 more
semanticscholar   +1 more source