Results 161 to 170 of about 2,043,921 (203)
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Synthesis of thiomorpholines by an intramolecular Ugi reaction
Tetrahedron Letters, 2002AbstractFor Abstract see ChemInform Abstract in Full Text.
Maria García-Valverde +2 more
exaly +4 more sources
Insight into the Mechanisms of the Multicomponent Ugi and Ugi–Smiles Reactions by ESI‐MS(/MS)
European Journal of Organic Chemistry, 2014 AbstractThe mechanisms of the Ugi and Ugi–Smiles reactions were investigated by using finely selected reaction conditions that allowed all of the intermediates to be “fish‐out” and characterized by ESI‐MS/MS. New insight into the Ugi and Ugi–Smiles reaction mechanisms is provided without using charge‐tagged reagents.
IACOBUCCI, CLAUDIO +3 more
openaire +2 more sources
Versatile Protecting-Group Free Tetrazolomethane Amine Synthesis by Ugi Reaction [PDF]
ACS Combinatorial Science, 2016 The use of ammonia in the Ugi reaction is often problematic due to low yields and multiple side reactions. Here, we report the use of ammonia in the tetrazole Ugi variation providing a clean, good-to-high yielding reaction, especially with ketones as oxo
Justyna Kalinowska-Tłuścik +2 more
exaly +3 more sources
Cyclic Imines in Ugi and Ugi-Type Reactions
ACS Combinatorial Science, 2020Ugi four-component reactions (U-4CRs) are widely recognized as being highly efficient for the synthesis of pseudopeptides. However, the products of these reactions are not so interesting as drug candidates because they are not conformationally restricted enough for a potent interaction with biological targets.
Mohammad Taghi Nazeri +3 more
openaire +2 more sources
Ugi Reaction with Isocyanoindoles.
ChemInform, 2004AbstractFor Abstract see ChemInform Abstract in Full Text.
M. A. Mironov +3 more
openaire +1 more source
Seven-component reactions by sequential chemoselective Ugi–Mumm/Ugi–Smiles reactions
Chemical Communications, 2010A seven-component reaction was accomplished by utilizing the different chemoselectivities of the Ugi-Mumm and the Ugi-Smiles reaction. The sequential multicomponent reactions led to highly diverse peptide and glycopeptide like structures.
Sebastian, Brauch +2 more
openaire +2 more sources
Tetrahedron, 2001
Abstract A variety of hydantoinimide and tetrazole derivatives was prepared by combining two different Ugi reactions (U-4CRs) in solid and liquid phases.
Friederike Constabel, Ivar Ugi
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Abstract A variety of hydantoinimide and tetrazole derivatives was prepared by combining two different Ugi reactions (U-4CRs) in solid and liquid phases.
Friederike Constabel, Ivar Ugi
openaire +1 more source
Skeletal Diversity by Ugi Four-Component Coupling Reaction and Post-Ugi Reactions
HETEROCYCLES, 2007Here we report a strategy to alter the skeletal complexity of Ugi four-component coupling reaction products by using allylations followed by ring-closing metathesis. Principal component analysis is also performed for these compounds.
Masato Oikawa +2 more
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“Isocyanide-free” Ugi reactions
Organic & Biomolecular Chemistry, 2009High-yielding Ugi reactions have been carried out with in situ-prepared isocyanides, derived from the reaction of bromide derivatives with silver and potassium cyanide, thus alleviating the burden of the preparation, purification and subsequent use of isocyanides in multicomponent reactions.
El Kaim, Laurent +2 more
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Homologation of Ugi and Passerini reactions using ynamides
Drug Discovery Today: Technologies, 2018Being important biological and pharmacological units, β-amino amides and β-acyloxy amides have a privileged position in both academia and industry. Developing a methods to prepare them has gained attention. Ynamides, which possess dual nucleophilic and electrophilic properties, are similar to isonitriles. In this review, usage of ynamides in the single
Bo, Huang, Sunliang, Cui
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