نتایج جستجو برای: n disubstituted urea

تعداد نتایج: 1007367  

Journal: :Journal of dairy science 1997
G A Broderick M K Clayton

Data from 35 trials with 482 lactating cows fed 106 diets were used to study the effects of animal and dietary factors on the relationship between milk and blood urea N and the value of milk urea N in the assessment of protein status. In two trials, urea N in whole blood and in blood plasma were closely related (r2 = 0.952); the slope was not significantly different from 1.0, and the intercept ...

Journal: :Journal of the American Chemical Society 2011
Li Huang William D Wulff

A method is described which provides for the direct asymmetric catalytic synthesis of trisubstituted aziridines from imines and diazo compounds. While unactivated imines were not reactive to α-diazo carbonyl compounds in which the diazo carbon was disubstituted, N-Boc imines react with both α-diazo esters and α-diazo-N-acyloxazolidinones to give trisubstituted aziridines with excellent diastere...

Journal: :Chemical communications 2016
Iker Riaño Estibaliz Díaz Uxue Uria Efraím Reyes Luisa Carrillo Jose L Vicario

The asymmetric synthesis of substituted pyrrolidines has been accomplished using a novel organocatalytic cyclization reaction promoted by a Cinchona alkaloid based primary amine. The reaction proceeds smoothly yielding pyrrolidine-2,2-dicarboxylates after in situ diastereoselective reduction with high levels of enantioselection. Furthermore, these adducts could be easily transformed into N-prot...

Journal: :Russian Journal of Organic Chemistry 2021

A series of N,N?-disubstituted selenoureas containing an adamantane fragment have been synthesized in 23–75% yields. Procedures for the isolation and purification aromatic isoselenocyanates improved. The chemical shift C=Se carbon nucleus 13C NMR spectra has refined. found to be promising as inhibitors not only epoxide hydrolase (sEH-H) but also phosphatase domains (sEH-P) human soluble hydrola...

Journal: :Organic & biomolecular chemistry 2007
Jia-Li Jiang Jia Ju Ruimao Hua

1,2-Disubstituted-3,4-dihydronaphthalenes could be conveniently synthesized with high yields by the cycloaddition reactions of easily available vinylarenes with electron-deficient alkynes such as dimethyl, or diethyl acetylenedicarboxylate, methyl phenylpropiolate in the presence of DMF.DMA (N,N-dimethylformamide dimethyl acetal) as organocatalyst.

Journal: :Organic & biomolecular chemistry 2017
Svatava Voltrová Mickaël Muselli Josef Filgas Václav Matoušek Blanka Klepetářová Petr Beier

Tetrafluoroethylene-containing azides are accessed in two steps (one pot) from tetrafluoroalkyl bromides by metalation and reaction with electrophilic azides. Subsequent copper(i)-catalyzed azide-alkyne cycloaddition afforded N-tetrafluoroethyl and N-tetrafluoroethylene 4-substituted 1,2,3-triazoles. In addition, the protocol for the synthesis of 4,5-disubstituted 1,2,3-triazoles is presented.

Journal: :Chemical communications 2014
Weiwei Luo Jiannan Zhao Chengkai Yin Xiaohua Liu Lili Lin Xiaoming Feng

An efficient catalytic asymmetric hetero-ene reaction of 5-methyleneoxazolines with 1,2-dicarbonyl compounds (including α-ketoesters and glyoxal derivatives) was realized using Ni(II)-N,N'-dioxide complexes as the catalysts. It provides a rapid, high yielding (up to 99%) route for the preparation of 2,5-disubstituted oxazole derivatives in a highly enantioenriched form (up to >99% ee) under mil...

2014
Andrew G Cairns Hans Martin Senn Michael P Murphy Richard C Hartley

5,6-Disubstituted phenanthridinium cations have a range of redox, fluorescence and biological properties. Some properties rely on phenanthridiniums intercalating into DNA, but the use of these cations as exomarkers for the reactive oxygen species (ROS), superoxide, and as inhibitors of acetylcholine esterase (AChE) do not require intercalation. A versatile modular synthesis of 5,6-disubstituted...

2011
Neus Mesquida Sara López-Pérez Immaculada Dinarès Ermitas Alcalde

The synthesis of multifunctional indenes with at least two different functional groups has not yet been extensively explored. Among the plausible synthetic routes to 3,5-disubstituted indenes bearing two different functional groups, such as the [3-(aminoethyl)inden-5-yl)]amines, a reasonable pathway involves the (5-nitro-3-indenyl)acetamides as key intermediates. Although several multistep synt...

2007
SCOTT S. SWANEK Clinton R. Krehbiel Gerald W. Horn Hebbie T. Purvis Carla L. Goad Carla Goad Carolyn Lunsford Donna Perry Joan Summers Tim Bodine

Five ruminally cannulated steers (initial BW = 375 ± 34 kg; ADG = 1.16 ± 0.13 kg) were used in a 5 x 5 Latin square design experiment to determine the effects of increasing urea level on intake, nutrient digestion, nitrogen balance and ruminal kinetics. Isocaloric (NEm = 2.11 Mcal/kg; NEg = 1.35 Mcal/kg) and isonitrogenous (2.24% N) steam-flaked corn-based diets with urea concentrations of 0.0,...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید