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Any of various derivatives of urea.

American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


1. (Elements & Compounds) any of a class of organic compounds derived from urea by replacing one or more of its hydrogen atoms by organic groups
2. (Elements & Compounds) any of a class of derivatives of urea and carboxylic acids, in which one or more of the hydrogen atoms have been replaced by acyl groups: includes the cyclic ureides, such as alloxan
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014


(ˈyʊər iˌaɪd, -ɪd)

an acyl urea.
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.
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References in periodicals archive ?
Tolstikov, Synthesis and antiviral activity of ureides and carbamates of betulinic acid and its derivatives, Bioorg.
For the leaf N content, the inoculated plants presented higher values owing to the efficiency of biological nitrogen fixation (BNF), which results in the production of ureides (allantoin and allantoic acid) in the nodules.
Johansen, "Prodrugs as drug delivery systems IV: N-Mannich bases as potential novel prodrugs for amides, ureides, amines, and other NH-acidic compounds," Journal of Pharmaceutical Sciences, vol.
Exceptions to this idea occur when urea is the chief cause of nitrogen supply, in species in which ureides play an significant physiological role (Martin and Ruby, 2004), when too much application of Zn, Cu, Mn, Fe, Ca, or Mg has been made over many years (Martin and Ruby, 2004), and possibly also in nitrogen-fixing crops grown on mineral-poor or highly nickel-fixing (high pH, high lime) soils.
Concentrations of ureides (allantion and allantoic acid) in xylem sap were measured as the phenylhydrazine derivative of glyoxylate (Young and Conway.
Sap was collected at the pod-fill stage by Vacuum Extraction Method and stored in the freezer at -15degC, then concentrations of ureides, nitrate and amino-N were determined to calculate the relative ureide- N (%) and percent nitrogen derived from atmosphere (% Ndfa) by the following formula:
In soybean, ureides (allantoin and allantoic acid) are the N transport molecules from the nodules to the leaves.
The substrates for mineralization are varied, and include such compounds as proteins, peptides, nucleic acids, aminopolysaccharides, urate, and ureides. Because the substrates are varied, the enzymes that are used to mineralize organic N are also varied.
Faizah AW, Suratmini P, Nurhayata DP, Bagnall DJ, Bergersen FJ (1991) Re-evaluation of the, role of ureides in the xylem transport of nitrogen in Arachis-spp.
The metabolic products of [N.sub.2] fixation in legumes are reported to be the amide asparagine or the ureides allantoin and allantoic acid (Streeter, 1991).
Role of amides, amino acids, and ureides in the nutrition of developing soybean seeds.
The ureides, allantoin and allantoic acid, were first identified as important nitrogenous compounds in soybean in 1970 by Ishizuka.