نتایج جستجو برای: Nitrones

تعداد نتایج: 453  

Journal: :Organic letters 2012
Dong-Liang Mo Donald A Wink Laura L Anderson

N-Vinyl nitrones derived from fluorenone have been prepared via a copper-mediated coupling between fluorenone oxime and vinyl boronic acids. These compounds undergo subsequent rearrangement and addition reactions that are distinct from the traditional [3 + 2] cycloaddition reactivity of nitrones. Thermal rearrangements of fluorenone N-vinyl nitrones give spiroisoxazolines, while treatment with ...

Journal: :Chemical communications 2015
Douglas A MacKenzie Allison R Sherratt Mariya Chigrinova Arnold J Kell John Paul Pezacki

Unnatural D-amino acids bearing endocyclic nitrones were developed for live-cell labelling of the bacterial peptidoglycan layer. Metabolic incorporation of D-Lys and D-Ala derivatives bearing different endocyclic nitrones was observed in E. coli, L. innocua, and L. lactis. The incorporated nitrones of these bacteria then rapidly underwent strain-promoted alkyne-nitrone cycloaddition (SPANC) rea...

Journal: :Acta pharmaceutica 2015
Mircea Dumitru Croitoru Hermina Iulia Petkes Ibolya Fülöp Remus Cotârlan Oana Elena Şerban Titica Maria Dogaru Şerban Andrei Gâz Florea Béla Tőkés Cornelia Majdik

Free radicals are involved in the development of reperfusion injuries. Using a spin trap, the intensity of such lesions can be reduced. Nitrones (effective in vivo spin traps) were tried in this work as in vivo nitric oxide donors. Nitrite and nitrate concentration values (rabbit blood) were used as biomarkers of nitric oxide production. Most nitrones did not increase plasma concentrations of n...

Journal: :Organic & biomolecular chemistry 2014
Roberta Majer Olga Konechnaya Ignacio Delso Tomas Tejero Orazio A Attanasi Stefania Santeusanio Pedro Merino

Asymmetric 1,3-dipolar cycloadditions between 1,2-diaza-1,3-dienes and chiral non-racemic nitrones to give 3-substituted-5-diazenyl isoxazolidines were studied both experimentally and theoretically. Whereas cyclic nitrones provide complete selectivity for the cycloaddition reaction (only one isomer is obtained), acyclic nitrones derived from D-glyceraldehyde and D-galactose lead to 1 : 1 mixtur...

Journal: :Molecules 2013
Hui Zhao Wen-Bo Zhao Jian-She Zhu Yue-Mei Jia Chu-Yi Yu

D-glucopyranose-derived and L-idopyranose-derived piperidine nitrones were synthesized in good overall yields through six-step reaction sequence starting from readily available 2,3,4,6-tetra-O-benzyl-D-glucopyranose. The method is efficient and could be general for the synthesis of aldohexose-derived piperidine nitrones which are precursors of piperidine iminosugars.

Journal: :Chemical communications 2008
Simon M Turega Christiane Lorenz Jan W Sadownik Douglas Philp

Nitrones undergo dynamic exchange in chloroform at room temperature through two mechanisms-hydrolysis and recombination or hydroxylamine addition/elimination; this dynamic exchange is harnessed to select a nitrone-based bis(amidopyridine) receptor for diacids from a group of four nitrones through its binding to a glutaric acid-based target.

Journal: :Organic & biomolecular chemistry 2013
Andrea M Hardman Sonia S So Anita E Mattson

Highly functionalized oxazinanes are efficiently prepared through urea-catalyzed formal [3 + 3] cycloaddition reactions of nitrones and nitrocyclopropane carboxylates. The reaction system is general with respect to both the nitrocyclopropane carboxylates and nitrones enabling the preparation of a large family of oxazinanes, typically in high yield. This method affords access to enantioenriched ...

Journal: :journal of sciences islamic republic of iran 0

a series of 1,3-dipolar cycloaddition reactions are carried out using cyclodimers of simple nitrones and various dipolarophiles; substituted isoxazolidines are isolated and identified. it is proved that such cyclodimers, in solution, are in equilibrium with their corresponding nitrones and enamines. it is also concluded that aldocyclodimers are more potent than keto-cyclodimers in establishing ...

Journal: :Annals of the New York Academy of Sciences 2002
Robert A Floyd Kenneth Hensley Michael J Forster Judith A Kelleher-Anderson Paul L Wood

Specific nitrones have been used for more than 30 years in analytical chemistry and biochemistry to trap and stabilize free radicals for the purpose of their identification and characterization. PBN (alpha-phenyl-tert-butyl nitrone), one of the more widely used nitrones for this purpose, has been shown to have potent pharmacologic activities in models of a number of aging-related diseases, most...

Journal: :Antioxidants 2023

Ischemic stroke is the leading cause of disability and second death worldwide. However, current therapeutic strategies are scarce limited efficacy. The abundance information available on molecular pathophysiology ischemic has sparked considerable interest in developing new neuroprotective agents that can target different events cascade may be used combination with existing treatments. In this r...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید