Results 31 to 40 of about 2,950 (153)
SynOpen, 2018 Biologically attractive azaspiro[4.5]trienones have been prepared via Ugi four-component reaction (Ugi-4CR) followed by bromine-mediated ipso-cyclization.
Saeed Balalaie +5 more
doaj +1 more source
The Catalytic Enantioselective Ugi Four‐Component Reactions [PDF]
Angewandte Chemie International Edition, 2018 Finally stereoselective: Enantioselective variations have been developed for many multicomponent reactions; however, it has been missing for the Ugi four-component reaction. This has now changed with the discovery of an efficient catalytic enantioselective variant for the four-component reaction of isocyanides, primary amines, aldehydes or ketones, and
Shabnam Shaabani, Alexander Dömling
openaire +2 more sources
Diastereoselective Ugi reaction for the synthesis of unnatural amino esters
Orbital: The Electronic Journal of Chemistry, 2012 Multicomponent Reactions (MCR) are useful reactions to obtain complex products by the simple mixture of 3 or more reactants. The classic Ugi reaction (4-UCR) involves a mixture of an amine, aldehyde, isocyanide and a carboxylic acid, giving peptoides as ...
Rafael Oliveira Rocha +4 more
doaj +1 more source
Substituent Effects in Ugi–Smiles Reactions
The Journal of Physical Chemistry A, 2013 In a recent communication, we described the mechanism of the well-known Ugi-type reactions with a model system (J. Org. Chem. 2012, 77, 1361-1366). Herein, focusing on the Ugi-Smiles coupling, we study the effects of each of the four reactants on the energy profile to further explain the experimental results.
Chéron, Nicolas +4 more
openaire +3 more sources
DFT Studies on the Stereoselective Three-Component Ugi Reaction
Orbital: The Electronic Journal of Chemistry, 2019 Mechanism and stereochemistry of three component Ugi reaction (3C-Ugi) were studied theoretically based on DFT calculations. Structures of reagents, products, intermediates, and transition states were optimized at M062X/6-31+g(d,p) level of theory in gas
Elaheh Sadat Sharifzadeh +1 more
doaj +3 more sources
Beilstein Journal of Organic Chemistry, 2014 An efficient Ugi three-component reaction of a preformed chiral ketimine derived from isatin with various isonitrile and acid components has been developed.
Giordano Lesma +4 more
doaj +1 more source
Advanced Science, EarlyView.Kinetic‐gated CRISPR–Cas12a activation enables single‐enzyme detection and spatiotemporal imaging of UDG ABSTRACT Uracil‐DNA glycosylase (UDG) is a key enzyme in base excision repair and an important biomarker for genomic stability and disease. In many reported sensing systems, uracil excision is coupled to signal generation through additional ...
Kejun Dong +12 more
wiley +1 more source
Beilstein Journal of Organic Chemistry, 2019 The synthesis of a novel category of pseudo-peptides via intramolecular Ugi reaction of levulinic acid (4-oxopentanoic acid), aromatic and aliphatic amines, and amino acid-based isocyanides is reported.
Maryam Khalesi +2 more
doaj +1 more source
Endoscopic features of cytomegalovirus disease of the upper gastrointestinal tract between transplant and non-transplant patients [PDF]
The Korean Journal of Internal MedicineBackground/Aims Cytomegalovirus (CMV) disease in the upper gastrointestinal (UGI) tract frequently occurs in immunocompromised patients. However, data regarding UGI CMV disease in non-transplant patients compared with those in transplant recipients are ...
Yuri Kim +10 more
doaj +1 more source
Molecules, 2022 An efficient method for the synthesis of functionalized peptidomimetics via multicomponent Ugi reaction has been developed. The application of trifluoroethanol (TFE) as a reaction medium provided desired products with good yields.
Parul Sahrawat +6 more
doaj +1 more source