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Journal articles on the topic 'Urea Amino compounds'

Author: Grafiati

Published: 4 June 2021

Last updated: 3 February 2022

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1

Guerrero-Alburquerque, Natalia, Shanyu Zhao, Daniel Rentsch, Matthias M. Koebel, Marco Lattuada, and Wim J. Malfait. "Ureido Functionalization through Amine-Urea Transamidation under Mild Reaction Conditions." Polymers 13, no. 10 (2021): 1583. http://dx.doi.org/10.3390/polym13101583.

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Ureido-functionalized compounds play an indispensable role in important biochemical processes, as well as chemical synthesis and production. Isocyanates, and KOCN in particular, are the preferred reagents for the ureido functionalization of amine-bearing compounds. In this study, we evaluate the potential of urea as a reagent to graft ureido groups onto amines at relatively low temperatures (<100 °C) in aqueous media. Urea is an inexpensive, non-toxic and biocompatible potential alternative to KOCN for ureido functionalization. From as early as 1864, urea was the go-to reagent for polyurea

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2

Perković, Ivana, Zrinka Rajić Džolić, and Branka Zorc. "A convenient synthesis of new NSAID esters containing amino acid, urea and amide moieties." Acta Pharmaceutica 63, no. 3 (2013): 409–18. http://dx.doi.org/10.2478/acph-2013-0023.

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Abstract A convenient synthetic method for the preparation of novel NSAID twin esters 6a-i containing amino acid residue, urea and amide moieties has been developed. The synthetic pathway applied for the preparation of target compounds and key intermediates 1-benzotriazolecarboxylic acid chloride (1), NSAID benzotriazolides 2a-c and N-(1-benzotriazolecarbonyl)-amino acids 3a-d involved benzotriazole as a synthetic auxiliary. The final preparation step of esters 6a-i included the solvent-free reaction of compounds 2a-c with amino acid derivatives 5a-g, bearing two hydroxyl groups, one at each t

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3

Janjanin, Danijela, Marko Karoglan, Mirjana Herak Ćustić, Marijan Bubola, Mirela Osrečak, and Igor Palčić. "Response of ‘Italian Riesling’ Leaf Nitrogen Status and Fruit Composition (Vitis vinifera L.) to Foliar Nitrogen Fertilization." HortScience 51, no. 3 (2016): 262–67. http://dx.doi.org/10.21273/hortsci.51.3.262.

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Two-year study was conducted on Italian Riesling cultivar with the aim to compare the effect of foliar sprays with different nitrogen forms on grapevine leaf N status, yield, and nitrogen compounds in grape juice. Treatments included no fertilization (control), soil NPK treatment, and three foliar treatments [amino acids, urea, ammonia (NH4+)/nitrate] applied four times during season, also treated with soil NPK. The application of 1% w/v urea significantly increased leaf total leaf N content in the second year of study. However, there were no effects on N compounds in grape juice, since change

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4

Hafez, Hend N., and Abdel-Rahman B. A. El-Gazzar. "Synthesis of Novel Pyridine Bearing Biologically Active Imidiazolyl, Pyrazolyl, Oxa/thiadiazolyl and Urea Derivatives as Promising Anticancer Agents." Current Organic Synthesis 17, no. 1 (2020): 55–64. http://dx.doi.org/10.2174/1570179417666191223163225.

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Background: A novel series of pyridine containing 1,3,4-oxa/thiadiazol derivatives 4a,b, pyrazole derivatives 5-7, thiazole derivatives 9a,b and 17a-c, urea derivatives 12a-c, imidiazole derivative 16, imidazo[1,2-a]pyridine derivatives 18a, b, tetrazole 19, pyrane 20 and pyridine derivatives 21 has been synthesized. Objective: This research aims to synthesize 6-(Trifluoromethyl)-2-[3-(trifluoromethyl)phenyl] amino nicotinohydrazide 2 and 6-(trifluoromethyl)-2-[3-(trifluoromethyl)phenyl]amino pyridin-3-carboaldhyde 15 as key intermediate for the synthesis of novel pyridine derivatives bearing

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5

Tang, Keyong, Weilin Li, Jie Liu, Cheng-Kung Liu, and Hongbo Pan. "Mechanism of Collagen Processed with Urea Determined by Thermal Degradation Analysis*." Journal of the American Leather Chemists Association 115, no. 10 (2020): 380–89. http://dx.doi.org/10.34314/jalca.v115i10.4172.

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During the beamhouse process for nappa leather, pelts are usually limed with amino compounds such as urea, ethylenediamine, and triethanolamine. However, the interaction between amino compounds and collagen is not well known. In this work, collagen fibers were soaked in various concentrations of urea and the thermal degradation of collagen fibers were studied by the methods Horowitz-Metzger and Coats-Redfern. The mechanism of the reaction between urea and collagen fibers is discussed, wherein the thermal degradation activation energy first decreases and then increases. The lowest thermal degra

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6

Katla, Ramana, Rasheed Syed, Madhava Golla, Adam Shaik, and Raju Chamarthi. "Synthesis and biological evaluation of novel urea and thiourea derivatives of valacyclovir." Journal of the Serbian Chemical Society 79, no. 3 (2014): 283–89. http://dx.doi.org/10.2298/jsc120716095k.

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A series of novel urea and thiourea derivatives of valacyclovir were efficiently synthesized in high yields and evaluated their antiviral activity. 2-((6-Amino-4-oxo-4,5-dihydro-1H-imidazo[4,5-c]pyridin-1-yl)methoxy)ethyl-2-amino-3-ethylbutanoate (valacyclovir) 1 is reacted with various aromatic isocyanates/thiocyanates 2 in the presence of N, N- dimethyl piperazine as a base in THF: pyridine (4:1) to obtain valacyclovir urea/thiourea derivatives 3(a-j). The structures of the title compounds 3(a-j) were confirmed by IR, NMR (1H, 13C), mass spectral and elemental analysis. The newly synthesized

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7

Honda, Ichiro, Makoto Sibagaki, Koichi Yoneyama, et al. "Photosystem II Inhibition by Phloroglucinol Derivatives Having Both Phenol and Urea Functionalities." Zeitschrift für Naturforschung C 48, no. 3-4 (1993): 159–62. http://dx.doi.org/10.1515/znc-1993-3-408.

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Abstract Esters of 3-nitrophloroglucinecarboxylic acid were found to be active photosystem II (PS II) inhibitors, as were the amides, indicating that, in their structures, the substituted phloroglucinol nuclei themselves plays a major roles in PS II inhibition. Among the phenylureidoalkyl esters tested, 3,4-dichlorophenylurea compound having two amino hydrogen atoms showed high activities. Optimal activity was associated with compounds in which the oxygen atom and the urea structure in the ester side chain were connected via an ethylene group.

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8

Kathiriya, P. J., H. D. Purohit, and Dipak M. Purohit. "Synthesis and Antimicrobial Activity of 2-{4'-[(6"-Aryl)2"-Hydroxy-3",4"-Dihydro-Pyrimidine-4"-yl]-Phenyl Amino}-6-[Bis (2'"-Chloroethyl) Amino]-4-Methoxy-1,3,5-Triazine." International Letters of Chemistry, Physics and Astronomy 49 (April 2015): 137–42. http://dx.doi.org/10.18052/www.scipress.com/ilcpa.49.137.

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The titled compounds (5a-5k) have been synthesized by the condensation of 2-{4'-[(3"-aryl)-2"-Propene-1"-one]-Phenyl amino}-6-[bis-2""-chloroethyl) amino]-4-methoxy-1,3,5-triazine with urea in presence of conc. HCl (0.3ml) The biological activities of these compounds have been examined against various Gram +ve, Gram –ve bacteria and fungi. The structure of the products was confirmed by IR, 1H NMR, Mass spectra and elemental analysis.

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9

Liu, Shenghui, Hailong He, Min Gan, Peng Yi та Xiaojian Jiang. "Catalytic Asymmetric Intramolecular Bromolactonization of α,β-Unsaturated Ketones". Synlett 30, № 12 (2019): 1474–78. http://dx.doi.org/10.1055/s-0037-1611860.

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Enantioselective bromolactonization by using an amino-urea catalyst to generate the important bromo-containing 3,4-dihydroisocoumarins is described. Excellent yields and good enantioselectivities could be achieved for various 3,4-dihydroisocoumarin compounds.

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10

Liu, Juan, Jing Ya Nan, Chun Peng Wang, Tie Ling Jin, and Ri Qing Chen. "Orthogonal Experimental Study on Moulding Conditions of Amino Moulding Plastic." Advanced Materials Research 900 (February 2014): 596–600. http://dx.doi.org/10.4028/www.scientific.net/amr.900.596.

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In this paper, the moulding conditions of urea-formaldehyde resin were optimized to prepare moulding plastic with good mechanical properties using orthogonal experimental design method. The effects of moulding temperature, pressure and pressing time on the impact strength and blending strength of urea-formaldehyde resin were studied and analyzed. The results showed that moulding temperature had most noticeable influence on the impact strength and blending strength of urea-formaldehyde moulding compounds. The ratio F of moulding temperature to the impact strength was 2.077; the ratio F of mould

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11

Arnold, Zdeněk, Miloš Buděšínský, and Magdalena Pánková. "Reactivity of triformylmethane. I. Reactions of triformylmethane with selected types of amino compounds." Collection of Czechoslovak Chemical Communications 56, no. 5 (1991): 1019–31. http://dx.doi.org/10.1135/cccc19911019.

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Reactions of triformylmethane with various types of amino compounds were investigated. Besides with ammonia, triformylmethane reacts spontaneously with primary amines, aminoacids and their esters, urea and related compounds including carbamic acid derivatives. Reactions with amides of carboxylic and sulfonic acids require catalysis with Lewis acids. Primary products are aminomethylenemalonaldehyde derivatives IIIa-IIIv. Reactions of triformylmethane with excess of selected primary amines and two secondary amines (dimethylamine and morpholine) were also studied.

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12

Chung, Suhman, Michaela Wendeler, Jason W. Rausch, et al. "Structure-Activity Analysis of Vinylogous Urea Inhibitors of Human Immunodeficiency Virus-Encoded Ribonuclease H." Antimicrobial Agents and Chemotherapy 54, no. 9 (2010): 3913–21. http://dx.doi.org/10.1128/aac.00434-10.

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ABSTRACT Vinylogous ureas 2-amino-5,6,7,8-tetrahydro-4H-cyclohepta[b]thiophene-3-carboxamide and N-[3-(aminocarbonyl)-4,5-dimethyl-2-thienyl]-2-furancarboxamide (compounds 1 and 2, respectively) were recently identified to be modestly potent inhibitors of the RNase H activity of HIV-1 and HIV-2 reverse transcriptase (RT). Both compounds shared a 3-CONH2-substituted thiophene ring but were otherwise structurally unrelated, which prevented a precise definition of the pharmacophore. We have therefore examined a larger series of vinylogous ureas carrying amide, amine, and cycloalkane modifications

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13

Journal, Baghdad Science. "Synthesis and Characterization of Some New Azo Dyes Derivatives Via Chalcone and Study Some of Their Biological Activity." Baghdad Science Journal 13, no. 1 (2016): 122–32. http://dx.doi.org/10.21123/bsj.13.1.122-132.

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This work includes synthesis of new six membered heterocyclic rings with effective amino group using the reaction of benzylideneacetophenone (chalcone) (1) with thiourea or urea in alcoholic basic medium to form: 1,3-thiazen-2-amine (2), and 1,3-oxazin-2-amine (8) respectively. The diazotization reaction was carried out with sodium nitrite in presence of hydrochloric acid to form diazonium salts which suffered coupling reaction with naphthols and phenols in the presence of sodium hydroxide to form colored azo dyes (4-7, and 10-13). o-methylation reaction of compounds (7) and (10) yielded : 1,3

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14

Bakibaev, A. A., S. Yu Panshina, O. V. Ponomarenko, V. S. Malkov, O. A. Kotelnikov, and A. K. Tashenov. "1D and 2D NMR spectroscopy for identification of carbamide-containing biologically active compounds." Bulletin of the Karaganda University. "Chemistry" series 101, no. 1 (2021): 71–81. http://dx.doi.org/10.31489/2021ch1/71-81.

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Urea (carbamide) is the main end product of amino acids' metabolism in mammals. Extensive research in the field of urea chemistryhas contributed to the creation of many biologically active and other compounds based on the carbamide fragment NH–CO–NH. The substituting groups of urea directly affect its properties and characteristics which are reflected in the NMR spectral data and this circumstance can be the basis for the identification of urea derivatives. In this work, chemical shifts in the NMR spectra of urea and its acyclic structure, barbituric series, imidazolidinone series and bicyclic

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15

Cheema-Dhadli, Surinder, and Mitchell L. Halperin. "Relative rates of appearance of nitrogen and sulphur: implications for postprandial synthesis of proteins." Canadian Journal of Physiology and Pharmacology 71, no. 2 (1993): 120–27. http://dx.doi.org/10.1139/y93-017.

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The purpose of this study was to gain insights on the temporal fate of proteins based on the rate of appearance of waste products of nitrogen (urea) and sulphur (sulphate) metabolism. Urine was collected every 2 h from 25 normal subjects to measure the rates of excretion of urea, creatinine, and sulphate throughout the 24-h cycle. Samples of blood and urine were also obtained over a 4-h period from 10 subjects who consumed a mixed meal containing 0.4 g protein/kg body weight to obtain information on the relative rates of degradation of amino acids with and without sulphur in a noninvasive fash

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16

Huntington, Gerald B. "Net absorption from portal-drained viscera of nitrogenous compounds by beef heifers fed on diets differing in protein solubility or degradability in the rumen." British Journal of Nutrition 57, no. 1 (1987): 109–14. http://dx.doi.org/10.1079/bjn19870014.

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1. The objective of the present study was to evaluate effects of in vitro rumen solubility or degradability of dietary protein on net absorption of nitrogenous compounds from portal-drained viscera of beef heifers.2. Four protein sources, casein, soya-bean meal, maize-gluten meal and blood meal provided about two-thirds of total dietary nitrogen in semi-purified diets given to four beef heifers in a 4 x 4 Latin square design.3. Although in vitro degradability of dietary N ranged from 842 (casein) to 310 (blood meal) g/kg total dietary N, net absorption of ammonia-N or α-amino-N was not signifi

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17

Padilla-Martínez, Itzia I., José Miguel González-Encarnación, Efrén V. García-Báez, Alejandro Cruz, and Ángel Andrés Ramos-Organillo. "Isothioureas, Ureas, and Their N-Methyl Amides from 2-Aminobenzothiazole and Chiral Amino Acids." Molecules 24, no. 18 (2019): 3391. http://dx.doi.org/10.3390/molecules24183391.

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In this investigation, the reaction of 2-dithiomethylcarboimidatebenzothiazole with a series of six chiral amino-acids was studied. The reaction proceeds through the isolable sodium salt of SMe-isothiourea carboxylates as intermediates, whose reaction with methyl iodide in stirring DMF as solvent affords SMe-isothiourea methyl esters. The presence of water in the reaction leads to the corresponding urea carboxylates as isolable intermediates, whose methyl esters were obtained. Finally, the urea N-methyl amide derivatives were isolated when SMe-isothiourea or urea methyl esters were reacted wit

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18

Farkens, Michael, Ion Neda та Reinhard Schmutzler. "Zur Chemie der 1,3,5-Triaza-2-phosphorinan-4,6-dione. Teil VIII. Weitere 1,3,5-Triaza-2 λ3-und 1,3,5-Triaza-2 λ4-phosphorinan-4,6-dione mit (2-Chlorethyl)amino-und Bis(2-chlorethyl)amino-Substituenten / Chemistry of the 1,3,5-Triaza-2-phosphorinan-4,6-diones. Part VIII. Further 1,3,5-Triaza-2λ3- and 1,3,5-Triaza-2λ4-phosphorinane-4,6-diones with (2-Chloroethyl)amino- and Bis(2-chloroethyl)amino Substituents". Zeitschrift für Naturforschung B 49, № 4 (1994): 445–50. http://dx.doi.org/10.1515/znb-1994-0403.

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In the reaction of 2-chloro-1,5-dimethyl-3-phenyl-1,3,5-triaza-2λ3-phosphorinane-4,6- dione (1) and 2-chloro-1,3,5-triphenyl-1,3,5-triaza-2λ3-phosphorinane-4,6-dione (2) with (2-chloroethyl)amine hydrochloride or bis(2-chloroethyl)amine hydrochloride in the presence of triethylamine the corresponding (2-chloroethyl)amino- and bis(2-chloroethyl)amino-substituted 2λ3-phosphorinane-4,6-diones (3-6) are formed. Oxidation with the hydrogen peroxide- urea-1: 1-adduct gives the corresponding 2-oxo-2λ4-phosphorinane-4,6-diones (7-10), in the same manner as described in the literature for the 1,3,5-tri

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19

Khouili, Mostafa, Maria Dolors Pujol, Hasna Yassine, et al. "Synthesis of New Dialkyl 2,2′-[Carbonylbis(azanediyl)]dibenzoates via Curtius Rearrangement." Synthesis 53, no. 11 (2021): 1971–79. http://dx.doi.org/10.1055/s-0040-1706643.

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AbstractThe 2-(alkylcarbonyl)benzoic acids obtained by esterification of phthalic anhydride are converted into azide derivatives: alkyl 2-[(azidocarbonyl)amino]benzoates and to ureas: dialkyl 2,2′-[carbonylbis(azanediyl)]dibenzoates. These transformations were carried out using classical Curtius rearrangement conditions in the presence of diphenylphosphoryl azide (DPPA) in a basic medium, followed by hydrolysis. Subsequently, a final condensation reaction of these urea derivatives enabled us to obtain, for the first time, the new alkyl derivatives, alkyl 2-[2,4-dioxo-1,2-dihydroquinazolin-3(4H

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20

Mertz, Isaac T., Nick E. Christians, and Adam W. Thoms. "Utilizing Branched-chain Amino Acids for Increasing Shoot Density and Establishment Rate in Creeping Bentgrass." HortTechnology 30, no. 1 (2020): 102–6. http://dx.doi.org/10.21273/horttech04514-19.

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The branched-chain amino acids (BCAA) leucine (L), isoleucine (IL), and valine (V) are synthesized in plants and are essential to growth in most organisms. These compounds can be absorbed by the plant when foliarly applied, but plant catabolism of BCAA is not completely understood. A recent study observed that BCAA applied in a 2:1:1 or 4:1:1 ratio (L:IL:V) increased creeping bentgrass (Agrostis stolonifera) shoot density compared with applications of equal urea nitrogen (N) at 3.03 lb/acre N. The present study investigated whether those increases could translate to a quicker establishment rat

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21

Křepelka, Jiří, Antonín Černý, Rudolf Kotva, Jaroslav Vachek, and Milan Mělka. "Some derivatives of 5-(2-amino-6-hydroxy-4-oxo-3,4-dihydro-5-pyrimidinyl)pentanoic acid." Collection of Czechoslovak Chemical Communications 51, no. 5 (1986): 1140–49. http://dx.doi.org/10.1135/cccc19861140.

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Using the chloride method esters II - X, amides XI - XIV, and condensates with amino acid esters XV - XVII were prepared from 5-(2-amino-6-hydroxy-4-oxo-3,4-dihydro-5-pyrimidinyl)pentanoic acid (I); the amides XIII and XIV were also prepared by aminolysis of ester II. The derivative of glycine, XVIII, was obtained on saponification of ester XV, also obtained by condensation of triethyl ester of N-(6,6-dicarboxyhexanol)glycine (XXIII) with guanidine hydrochloride in a medium containing sodium ethylate. Hydrazinolysis of ethyl ester XXIV gave hydrazine XIX. Disubstituted ureas XX - XXI were obta

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22

Miyaji, Ryota, Yuuki Wada, Akira Matsumoto, Keisuke Asano, and Seijiro Matsubara. "Bifunctional organocatalysts for the asymmetric synthesis of axially chiral benzamides." Beilstein Journal of Organic Chemistry 13 (August 2, 2017): 1518–23. http://dx.doi.org/10.3762/bjoc.13.151.

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Bifunctional organocatalysts bearing amino and urea functional groups in a chiral molecular skeleton were applied to the enantioselective synthesis of axially chiral benzamides via aromatic electrophilic bromination. The results demonstrate the versatility of bifunctional organocatalysts for the enantioselective construction of axially chiral compounds. Moderate to good enantioselectivities were afforded with a range of benzamide substrates. Mechanistic investigations were also carried out.

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23

Shelp, Barry J., Konrad Sieciechowicz, Robert J. Ireland, and Kenneth W. Joy. "Determination of urea and ammonia in leaf extracts: application to ureide metabolism." Canadian Journal of Botany 63, no. 6 (1985): 1135–40. http://dx.doi.org/10.1139/b85-156.

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Methods are described for the routine determination of urea and ammonia in plant tissues. Ureido compounds such as allantoin and allantoate interfere with the urea assay but can be conveniently removed by ion-exchange chromatography prior to the color reaction with α-isonitrosopropiophenone. This assay was used to examine the effect of the urease inhibitor acetohydroxamate on leaf urea levels. A survey of methods for ammonia determination showed that for plant extracts and assay mixtures containing amides, microdiffusion followed by nesslerization provided a convenient and reliable technique.

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Hortin, Glen L., and Bonnie Meilinger. "Cross-Reactivity of Amino Acids and Other Compounds in the Biuret Reaction: Interference with Urinary Peptide Measurements." Clinical Chemistry 51, no. 8 (2005): 1411–19. http://dx.doi.org/10.1373/clinchem.2005.052019.

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Abstract Background: Biuret assays for total protein measurement are considered to react with all peptides longer than 2 residues. Some studies using biuret assays of urine suggest that small peptides generally are more abundant than proteins in urine, but it is not clear whether this is a problem of assay specificity. Methods: We analyzed the specificity and kinetics of a biuret reaction for solutions of amino acids, organic compounds, peptides, proteins, and ultrafiltered urine specimens and compared the results with standard clinical assays for protein measurement. Results: The biuret assay

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Mao, Li-Juan, та Ru-Yu Chen. "Highly Selective Arbuzov Reaction of α-Chlorocarbonyl Compounds with P(OEt)3 and Substituted Amino Urea". Phosphorus, Sulfur, and Silicon and the Related Elements 111, № 1 (1996): 167. http://dx.doi.org/10.1080/10426509608054796.

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Walt, JGvan der. "Nitrogen metabolism of the ruminant liver." Australian Journal of Agricultural Research 44, no. 3 (1993): 381. http://dx.doi.org/10.1071/ar9930381.

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This review examines both the quantitative flux of nitrogenous compounds from the portaldrained viscera (PDV) to the liver and the metabolic pathways within these tissues that facilitate interactions between these compounds. In order to estimate the flow of material between organs, it is necessary to be able to measure the rate of blood flow perfusing the organ under investigation. Methods of estimating blood flow are discussed. In general, splanchnic blood flow (c. 125 mL min-1kg-0.75 at maintenance feeding) is proportional to the intake of energy. Although the splanchnic bed only constitutes

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Bisht, Ajay Singh, and Rajat Bisht. "Microwave assested synthesis of phthalimide amino derivatives with their antioxidant potential." Current Trends in Pharmacy and Pharmaceutical Chemistry 3, no. 3 (2021): 23–27. http://dx.doi.org/10.18231/j.ctppc.2021.007.

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Imide is the configuration of amide in which the nitrogen atom is affix to two carbonyl group. Imide mention to any compound which carry the divalent radical. Phthalimide possess a structural feature CHNO and an imide ring which help them to be biologically active and pharmaceutically useful.Phthalimides have served as starting materials and intermediates for the synthesis of many types of alkaloids and pharmacophores.In view of broad biological activity of phthalimide, we herein plan to synthesize a series of new phthalimide derivatives by incorporating new pharmacophores at various positions

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Ono, Yuki, Masashige Fukasawa, Kuni Sueyoshi, et al. "Application of Nitrate, Ammonium, or Urea Changes the Concentrations of Ureides, Urea, Amino Acids and Other Metabolites in Xylem Sap and in the Organs of Soybean Plants (Glycine max (L.) Merr.)." International Journal of Molecular Sciences 22, no. 9 (2021): 4573. http://dx.doi.org/10.3390/ijms22094573.

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Soybean (Glycine max (L.) Merr.) plants form root nodules and fix atmospheric dinitrogen, while also utilizing the combined nitrogen absorbed from roots. In this study, nodulated soybean plants were supplied with 5 mM N nitrate, ammonium, or urea for 3 days, and the changes in metabolite concentrations in the xylem sap and each organ were analyzed. The ureide concentration in the xylem sap was the highest in the control plants that were supplied with an N-free nutrient solution, but nitrate and asparagine were the principal compounds in the xylem sap with nitrate treatment. The metabolite conc

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Portada, Tomislav, Davor Margetić, and Vjekoslav Štrukil. "Mechanochemical Catalytic Transfer Hydrogenation of Aromatic Nitro Derivatives." Molecules 23, no. 12 (2018): 3163. http://dx.doi.org/10.3390/molecules23123163.

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Mechanochemical ball milling catalytic transfer hydrogenation (CTH) of aromatic nitro compounds using readily available and cheap ammonium formate as the hydrogen source is demonstrated as a simple, facile and clean approach for the synthesis of substituted anilines and selected pharmaceutically relevant compounds. The scope of mechanochemical CTH is broad, as the reduction conditions tolerate various functionalities, for example nitro, amino, hydroxy, carbonyl, amide, urea, amino acid and heterocyclic. The presented methodology was also successfully integrated with other types of chemical rea

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Álvarez-Cáliz, Carmen, Inés M. Santos-Dueñas, Ana M. Cañete-Rodríguez, Teresa García-Martínez, Juan C. Mauricio, and Isidoro García-García. "Free amino acids, urea and ammonium ion contents for submerged wine vinegar production: influence of loading rate and air-flow rate." Acetic Acid Bacteria 1, no. 1 (2012): 1. http://dx.doi.org/10.4081/aab.2012.e1.

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The nitrogen source for acetic acid bacteria is important during the vinegar making process. There can be great variation in the final result according to the specific source, the total nitrogen availability and the operational conditions. These bacteria use L-proline, L-leucine and ammonium ion as their main source of nitrogen from white wine. The effect of loading and air-flow rates on the changes in amino acids, urea and ammonium ion contents have been studied for a semi-batch submerged wine vinegar controlled production. Experiments were carried out in a Frings 8L fermenter working in a se

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Casado, J., X. Remesar, and M. Pastor-Anglada. "Hepatic uptake of amino acids in late-pregnant rats. Effect of food deprivation." Biochemical Journal 248, no. 1 (1987): 117–22. http://dx.doi.org/10.1042/bj2480117.

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Hepatic availability, uptake and fractional extraction of amino acids were estimated in anaesthetized 21-day-pregnant and age-matched virgin rats, either fed or after 24 h starvation. Amino acid availability was unaltered in fed pregnant rats as compared with fed virgin controls. However, the hepatic uptake of these compounds was higher in the former than in the latter. These adaptations were mediated by an increase in the hepatic capability to take up amino acids in late-pregnant rats, as reflected by the changes found for the fractional extraction rates. The decrease in amino acid availabili

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Singh, Parminder, and Divya Gupta. "Recurrent encephalopathy and hyperammonemia in new born: case of arginosuccinic aciduria." International Journal of Contemporary Pediatrics 5, no. 6 (2018): 2350. http://dx.doi.org/10.18203/2349-3291.ijcp20184308.

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Urea cycle disorders result from defects in the metabolism of waste nitrogenous compounds derived from the breakdown of proteins and other nitrogen-containing molecules. Argininosuccinic aciduria is a rare autosomal recessive heterogeneous urea cycle disorder, which leads to the accumulation of argininosuccinic acid in the blood and urine. It is caused by defect in the argininosuccinate lyase (ASL) gene, which regulates the breakdown of argininosuccinate to fumarate and arginine in the urea cycle. They are a heterogeneous group of disorders which are associated with hyperammonemia resulting in

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Zhang, Zhenyu, Ming Li, Xiaoyin Zhang, Nan Zheng, Shengguo Zhao, and Jiaqi Wang. "A Novel Urease Inhibitor of Ruminal Microbiota Screened through Molecular Docking." International Journal of Molecular Sciences 21, no. 17 (2020): 6006. http://dx.doi.org/10.3390/ijms21176006.

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Inhibition of the urease activity of ruminal microbiota is not only beneficial for increasing dietary and endogenic urea-N utilization efficiency in ruminants but also might be applicable for the preservation of nitrogen fertilizer in soil and treatment of gastrointestinal and urinary tract infections caused by ureolytic bacteria. To discover urease inhibitors to efficiently target ruminal microbiota, the identified ruminal microbial metagenomic urease gene was used to construct a homology model to virtually screen urease inhibitors from the ChemDiv database by molecular docking. The GMQE and

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Alemany, Marià. "The problem of nitrogen disposal in the obese." Nutrition Research Reviews 25, no. 1 (2012): 18–28. http://dx.doi.org/10.1017/s0954422411000163.

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Amino-N is preserved because of the scarcity and nutritional importance of protein. Excretion requires its conversion to ammonia, later incorporated into urea. Under conditions of excess dietary energy, the body cannot easily dispose of the excess amino-N against the evolutively adapted schemes that prevent its wastage; thus ammonia and glutamine formation (and urea excretion) are decreased. High lipid (and energy) availability limits the utilisation of glucose, and high glucose spares the production of ammonium from amino acids, limiting the synthesis of glutamine and its utilisation by the i

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Pavlík, M., D. Pavlíková, J. Balík, and M. Neuberg. "The contents of amino acids and sterols in maize plants growing under different nitrogen conditions." Plant, Soil and Environment 56, No. 3 (2010): 125–32. http://dx.doi.org/10.17221/214/2009-pse.

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The effect of nitrogen nutrition on phytosterol and amino acid content in aboveground biomass of maize (<I>Zea mays</I> L.) was investigated in a pot experiment. For cultivation of maize plants nitrogen dose (2 or 4 g N/pot) was applied in the form of ammonium nitrate (AN) for control treatments or urea ammonium nitrate solution (UAN). UAN solution was applied according to the CULTAN method (Controlled Uptake Long Term Ammonium Nutrition). The content of amino acids as important nitrogen-containing compounds in plant biomass was affected by nitrogen nutrition. An increase of glutam

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Mertz, Isaac T., Nick E. Christians, and Adam W. Thoms. "Branched-chain Amino Acids for Use as a Nitrogen Source on Creeping Bentgrass." HortTechnology 29, no. 6 (2019): 833–37. http://dx.doi.org/10.21273/horttech04423-19.

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Amino acids have been reported to improve turfgrass growth compared with mineral nutrition; however, amino acid catabolism in plants has not been well studied. A number of turfgrass fertilizers contain amino acids; however, some amino acids may be more effective additives in fertilizers than others. Three amino acids that could be effective nitrogen sources for plant growth are the branched-chain amino acids (BCAAs). The BCAA leucine (L), isoleucine (IL), and valine (V) could be effective additives because they are nonpolar and hydrophobic, which can promote plant uptake of these compounds. Al

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Grbović, Ljubica M., Ksenija J. Pavlović, Suzana S. Jovanović-Šanta, and Bojana R. Vasiljević. "Microwave-Assisted Synthesis of Bile Acids Derivatives: An Overview." Current Organic Chemistry 23, no. 3 (2019): 256–75. http://dx.doi.org/10.2174/1385272823666190213114104.

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: The first attempts at microwave-assisted (MW) syntheses of bile acid derivatives were performed in domestic MW appliances. However, the reproducibility of these syntheses, which were performed in uncontrolled conditions, was very low. In the first part of this overview, compounds synthesized under such conditions are presented. Consequently, with the development of MW technology, MW-assisted reactions in MW reactors became reproducible. Thus, in the second part of this review, syntheses of bile acidsbased compounds in MW reactors are presented. Among others, publications dealing with the fol

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Timperley, M. H., R. J. Vigor-Brown, M. Kawashima, and M. Ishigami. "Organic Nitrogen Compounds in Atmospheric Precipitation: Their Chemistry and Availability to Phytoplankton." Canadian Journal of Fisheries and Aquatic Sciences 42, no. 6 (1985): 1171–77. http://dx.doi.org/10.1139/f85-145.

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Urea accounted for 30, 36, and 56%, respectively, of the water-soluble organic nitrogen (DON) compounds deposited from the atmosphere at two sites in New Zealand and one site in japan. The other DON compounds were not identified but they were all of low molecular size, apparently anionic, and did not include detectable quantities of amino acids or uric acid. In axenic culture, Chlorella spp. grew successfully using DON from New Zealand precipitation as its only source of N; Pediastrum biwae, a phytoplankton endemic to Lake Biwa in Japan, also achieved successful growth using DON separated from

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Fischer, Axel, Ion Neda, Thomas Kaukorat, Ralf Sonnenburg, Peter G. Jones, and Reinhard Schmutzler. "Beiträge zur Chemie des 4,5-Benzo-3-methyl-1,3,2-oxazaphosphorinan- 6-on Ringsystems: Röntgenstrukturanalysen an einem Bis(2-chlorethyl)amino- und einem Acetamido-substituierten Derivat / Chemistry of the 4,5-Benzo-3-methyl-1,3,2-oxazaphosphorinan-6-one Ring System: X-Ray Crystal Structure Analysis of a Bis(2-chloroethyl)amino- and of an Acetamido-Substituted Derivative." Zeitschrift für Naturforschung B 49, no. 7 (1994): 939–49. http://dx.doi.org/10.1515/znb-1994-0715.

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Abstract The reaction of 4,5-benzo-2-chloro-3-methyl-1,3,2-oxazaphosphorinan-6-one 1 with 1,2-bis- (trimethylsiloxy)ethane led to the bisphosphoryl species 2a and to the isomeric bisphosphite derivative 2b. The reaction of 1 with heptamethyldisilazane furnished the expected diphosphorus compound 3, with two λ3P(III) atoms linked by a methylamino group. Substitution of the chlorine atom of 1 by the 2-chloroethylamino and bis(2-chloroethyl)amino group led to the oxazaphosphorinanones 4 and 6. By oxidation of 4 with the hydrogen peroxide/urea 1:1-adduct, the phosphoryl compound 5 was formed. Oxi

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Andersen, Peter C., Brent V. Brodheck, and Russell F. Mizell. "Inoculation- and Fertilization-mediated Changes in Xylem Fluid Chemistry of Soybean and Subsequent Effects on Leafhopper Performance." HortScience 30, no. 4 (1995): 879A—879. http://dx.doi.org/10.21273/hortsci.30.4.879a.

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The xylophagous leafhopper, Homalodisca coagulata (Say), is an important vector of diseases caused by Xylella fastidiosa (e.g., Pierce's disease, phony peach disease, plum leaf scald, etc.). The nutritional status of xylem fluid has a profound influence on leafhopper distribution, feeding, and performance. Xylem fluid typically consists of 95% to 99% water and contains organic compounds (mainly amino acids and organic acids) in low concentration (i.e., 2 to 8 mM). Successful development of this highly polyphagous leafhopper depended on host-plant chemistry. The reasons for variable success on

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De Cian, M., M. Regnault, and F. H. Lallier. "Nitrogen metabolites and related enzymatic activities in the body fluids and tissues of the hydrothermal vent tubeworm Riftia pachyptila." Journal of Experimental Biology 203, no. 19 (2000): 2907–20. http://dx.doi.org/10.1242/jeb.203.19.2907.

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The distribution of nitrogen metabolism end-products and the associated enzyme activities, free amino acids and purine base catabolites were investigated in all the body compartments (circulating fluids and tissues) of the hydrothermal vent tubeworm Riftia pachyptila to acquire a general overview of nitrogen metabolism in this symbiotic organism. There were striking differences between the symbiont-containing trophosome tissue and other host tissues. High concentrations of ammonia, creatinine and, in particular, urate were found in all tissues, but they were present at consistently higher conc

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Kingsbury, Joanne M., Alan L. Goldstein, and John H. McCusker. "Role of Nitrogen and Carbon Transport, Regulation, and Metabolism Genes for Saccharomyces cerevisiae Survival In Vivo." Eukaryotic Cell 5, no. 5 (2006): 816–24. http://dx.doi.org/10.1128/ec.5.5.816-824.2006.

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ABSTRACT Saccharomyces cerevisiae is both an emerging opportunistic pathogen and a close relative of pathogenic Candida species. To better understand the ecology of fungal infection, we investigated the importance of pathways involved in uptake, metabolism, and biosynthesis of nitrogen and carbon compounds for survival of a clinical S. cerevisiae strain in a murine host. Potential nitrogen sources in vivo include ammonium, urea, and amino acids, while potential carbon sources include glucose, lactate, pyruvate, and fatty acids. Using mutants unable to either transport or utilize these compound

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Linnik, О. P., N. P. Smirnova, and A. М. Eremenko. "Peculiarities of sol-gel synthesis of co-modified by nitrogen and metal ions (Zn2+, Zr4+, Pt2+) semiconductive TiO2 films." Reports of the National Academy of Sciences of Ukraine, no. 12 (December 2020): 67–74. http://dx.doi.org/10.15407/dopovidi2020.12.067.

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According to the XPS investigation of titania films co-modified by nitro gen and metal ions obtained via sol-gel method, the formation of common bonds between elements occurs due to the presence of metal ions. The mechanism of urea thermolysis is changed as a result of the ability of metal ions to form the complex compounds with urea molecules under the reported synthesis conditions that, in turn, depends on the nature of metal ions, leading to the different chemical compositions of materials’ surface. The XPS data show that nitrogen atoms are surrounded by nonmetal ones on the surface of the

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Kanamori, Takeshi, Norihisa Kanou, Haruyuki Atomi, and Tadayuki Imanaka. "Enzymatic Characterization of a Prokaryotic Urea Carboxylase." Journal of Bacteriology 186, no. 9 (2004): 2532–39. http://dx.doi.org/10.1128/jb.186.9.2532-2539.2004.

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ABSTRACT We identified the first prokaryotic urea carboxylase (UCA) from a member of the alpha subclass of the class Proteobacteria, Oleomonas sagaranensis. This enzyme (O. sagaranensis Uca) was composed of 1,171 amino acids, and its N-terminal region resembled the biotin carboxylase domains of various biotin-dependent carboxylases. The C-terminal region of the enzyme harbored the Met-Lys-Met motif found in biotin carboxyl carrier proteins. The primary structure of the enzyme was 45% identical to that of the urea carboxylase domain of urea amidolyase from Saccharomyces cerevisiae. O. sagaranen

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Huntington, Gerald B., and Joan H. Eisemann. "386 Past, present and future of protein and N metabolism in ruminants." Journal of Animal Science 98, Supplement_4 (2020): 169–70. http://dx.doi.org/10.1093/jas/skaa278.311.

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Abstract By 1900, research identified urea, ammonia, and protein as the basic components of N metabolism in ruminants. Energy and protein metabolic interactions were outlined, amino acids were individually recognized as constituents of protein molecules, and the concept of enzyme-catalyzed reactions was established. Research stations were publishing research results and feeding recommendations. By 2000, the National Research Council built on the work of Henry and Morrison to create and revise publications of nutrient requirements for various classes of ruminants. Use of surgically altered anim

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Stefaniu, Amalia, Lucia Pintilie, Veronica Anastasoaie, and Eleonora-Mihaela Ungureanu. "In silico Evaluation of Antimicrobial Activity of Some Thiadiazoles Using Molecular Docking Approach." Chemistry Proceedings 3, no. 1 (2020): 116. http://dx.doi.org/10.3390/ecsoc-24-08319.

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Molecular docking studies have been performed to assess the antimicrobial potential of three 1,3,4-thiadiazole derivatives containing azulene rings. The simulations were conducted on Mycobacterium tuberculosis DNA gyrase, Staphylococcus aureus DNA gyrase, and Escherichia coli DNA adenine methylase. The relationships between the structures of compounds and their potential antimicrobial activity were investigated. Interactions with amino acid residues from the active binding site were elucidated and the results of docking are reported in terms of docking score. Better docking scores are obtained

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Lee, P. L., and R. H. Slocum. "A high-resolution method for amino acid analysis of physiological fluids containing mixed disulfides." Clinical Chemistry 34, no. 4 (1988): 719–23. http://dx.doi.org/10.1093/clinchem/34.4.719.

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Abstract In this paper we report a high-resolution method and special buffers for the analysis for 45 common amino acids and related compounds and seven less-common components occasionally found in physiological fluids. Careful optimization of the chromatographic protocol resolves cysteine-penicillamine mixed disulfide, penicillamine disulfide, and dihydroxyphenylalanine from cystine and methionine; cysteine-homocysteine mixed disulfide is eluted between tyrosine and phenylalanine. Argininosuccinic acid is eluted before ethanolamine; glycerophosphoethanolamine is separated from taurine; glucos

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El-Sayed, Wael A., Mahmoud M. M. Ramiz та Adel A. H. Abdel-Rahman. "Anti-Hepatitis B Virus Activity of New N4-β-D-Glycoside Pyrazolo[3,4-d]pyrimidine Derivatives". Zeitschrift für Naturforschung C 64, № 5-6 (2009): 323–28. http://dx.doi.org/10.1515/znc-2009-5-603.

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1The reaction of 6-hydrazinyl-1,3-dimethylpyrimidine-2,4-(1H,3H)-dione () with ethoxymethylenemalononitrile afforded 5-amino-1-(1,3-dimethyl-2,6-dioxo-1,2,3,6-tetrahydropyrimidin- 6-yl)-1H-pyrazole-4-carbonitrile (2). The latter was reacted with formamide and urea affording the corresponding 4-aminopyrazolo[3,4-d]pyrimidines 3 and 4. The reaction of monosaccharide aldoses with 3 and 4 gave stereoselectively the β-N-glycosides 5a - d and 6a - d which were treated with acetic anhydride in pyridine to afford the corresponding acetylated derivatives 7a - d and 8a - d. The prepared compounds were t

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Orò, Juan, and Cristiano B. Cosmovici. "Comets and Life on the Primitive Earth." International Astronomical Union Colloquium 161 (January 1997): 97–120. http://dx.doi.org/10.1017/s0252921100014639.

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AbstractComets may have contributed substantial amounts of water, volatiles and organic precursors such as HCN for the synthesis of biochemical compounds on the primitive Earth. This suggestion followed closely the prebiotic synthesis of adenine, purines and amino acids from HCN. Recent studies on the terrestrial heavy noble gases provide evidence that comets are the principal external source of Earth’s volatiles. During the encounter of comet Halley strong jets of CN, C2, C3and NH2were measured from Earth observatories, and by spacecraft mass spectrometry HCN, formaldehyde, adenine and many o

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Chan-Chan, Lerma H., Gerardo González-García, Rossana F. Vargas-Coronado, et al. "Characterization of model compounds and poly(amide-urea) urethanes based on amino acids by FTIR, NMR and other analytical techniques." European Polymer Journal 92 (July 2017): 27–39. http://dx.doi.org/10.1016/j.eurpolymj.2017.04.014.

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