1468-42-4Relevant academic research and scientific papers
Ammonium Chloride-Promoted Rapid Synthesis of Monosubstituted Ureas under Microwave Irradiation
Lan, Chunling Blue,Auclair, Karine
supporting information, p. 5135 - 5146 (2021/10/19)
Monosubstituted ureas are important scaffolds in organic chemistry. They appear in various biologically active compounds and serve as versatile precursors in synthesis. Monosubstituted ureas were originally prepared using toxic and hazardous phosgene equivalents. Modern methods include transamidation of urea and nucleophilic addition to cyanate salts, both of which suffer from a narrow substrate scope due to the need for a strong acid and prolonged reaction times. We hereby report that ammonium chloride can promote the reaction between amines and potassium cyanate to generate monosubstituted ureas in water. This method proceeds rapidly under microwave irradiation and tolerates a broad range of functional groups. Unlike previous strategies, it is compatible with other nucleophiles, acid-labile moieties, and most of the common protecting groups. The products precipitate out of solution, allowing facile isolation without column chromatography.
Avidin and streptavidin ligands based on the glycoluril bicyclic system
Hidalgo-Fernandez, Pedro,Ayet, Eva,Canal, Ivan,Farrera, Joan-Antoni
, p. 3147 - 3154 (2008/02/14)
Glycoluril derivatives with a carboxylic acid side chain have been synthesized and shown to bind to both avidin and streptavidin. Introduction of a valerate side chain in glycoluril led to an increased binding to both proteins only when the valerate group was bound to a N atom and with the proper stereochemistry [(+)-enantiomer]. On the other hand, introduction of the valerate side chain either on the bridgehead carbon or on the N atom with the opposite stereochemistry [(-)-enantiomer] led to a decrease in binding constant compared with unsubstituted glycoluril. Direct spectrophotometric competitive titration of each protein with a racemic ligand allowed measurement of the enantioselectivity of the ligand-protein complexation, together with the binding constant of the two enantiomers. In the case of the N-substituted glycoluril, the extension of the side chain by one methylene group, from valerate to caproate, led to an increase in the binding constant to both proteins. Docking studies using AutoDock 3.05 have been performed in order to predict the binding modes of these ligands to streptavidin. The effect of the stereochemistry and the position of the side chain on the binding constant to streptavidin is discussed in view of the predicted binding modes. The Royal Society of Chemistry 2006.
REACTIONS OF 6-AMINOHEXANOIC ACID WITH UREAS
Kornilina, A. N.,Zil'berman, E. N.,Spasskaya, R. I.,Matveeva, G. N.
, p. 808 - 811 (2007/10/02)
In aqueous alkaline solutions 1-alkyl-, 1,1-dialkyl-, acetyl-, and benzylureas and biuret react with 6-aminohexanoic acid, forming 6-ureidohexanoic acids.Arylureas react with 6-aminohexanoic acid with the formation of 6-(3-arylureido)hexanoic acids. 1,4-Disubstituted ureas do not react with 6-aminohexanoic acid.
Combating fungi with 1-(ω-substituted pentyl)-3-(2-cyano-acetyl)-ureas
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, (2008/06/13)
1-(ω-Substituted pentyl)-3-(2-cyano-acetyl)-ureas of the formula STR1 in which R represents R1, CO--R2, CO--NH--R3 or CO--OR4, R1 represents unsubstituted alkyl with 1 to 10 carbon atoms; or represents substituted alkyl with 1 to 4 carbon atoms, which contains, as a substituent, a vinyl group, an alkynyl group with up to 4 carbon atoms, an alkylcarbonyl group with 2 to 5 carbon atoms, an alkoxycarbonyl group with 2 to 5 carbon atoms, an alkenoxycarbonyl or alkynoxycarbonyl group with 4 to 5 carbon atoms, an aminocarbonyl group, an N-alkylaminocarbonyl or N-cycloalkylaminocarbonyl group with up to 7 carbon atoms in either case or a N-phenylaminocarbonyl group, which can optionally have C1 -C4 alkyl and/or chlorine as further substituents on the phenyl radical; or represents benzyl, which can be substituted in the aromatic part by a methyl, methoxy, methylenedioxy, nitro, trifluoromethyl, benzoyl, monochlorobenzoyl, dichlorobenzoyl, phenyl or phenoxy group or by 1 to 4 chlorine atoms; R2 represents a straight-chain or branched, saturated or unsaturated hydrocarbon radical with up to 8 carbon atoms, which can be substituted by chlorine or bromine or by a cyano group, R3 represents a straight-chain or branched alkyl radial with up to 11 carbon atoms, which can be substituted by a cyano group of by an alkoxycarbonyl radical with up to 5 carbon atoms, or represents a phenyl radical, which can be substituted y a methyl, nitro or trifluoromethyl group or by chlorine, R4 represents a saturated or unsaturated aliphatic group with up to 4 carbon atoms, Q represents CN, CO--NH2, COOH or CO--OR5, and R5 denotes an alkyl group with 1 to 4 carbon atoms, which possess fungicidal properties.
