نتایج جستجو برای: 13 dipolar cycloaddition

تعداد نتایج: 343672  

1,3-dipolar cycloaddition reaction of 1 mol or 2 mol of dibenzalaceton with 1 mol of non-stabilized azomethinylides generated in situ by decarboxylative condensation of isatin and proline or sarcosine give the novel new spiro-oxindolo(pyrrolizidines/ pyrrolidines) instead of bis-spirooxindolo( pyrrolizidines/ pyrrolidines).

Journal: :Organic & biomolecular chemistry 2005
Zoltán Kaleta Orsolya Egyed Tibor Soós

Highly efficient fluorous tagging methodology was developed based on catalytic 1,3-dipolar cycloaddition as the key step.

Journal: :Chemical communications 2010
Frédéric Lincker Philippe Bourgun Helen Stoeckli-Evans Isabel M Saez John W Goodby Robert Deschenaux

A synthetic methodology based on the 1,3-dipolar cycloaddition reaction was developed to design enantiomerically pure liquid-crystalline fullerodendrimers.

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 establish...

In this protocol, we report a novel approach for the synthesis of a new class of heterocyclic 1H-1,2,3-triazole-modified peptidomimetic compounds. The process consists of an Ugi four-component condensation reaction of amines, an isocyanide, an aldehyde and acids followed by a Huisgen 1,3-dipolar cycloaddition reaction with an azide group in the presence of a catalytic amount of CuSO4</...

Journal: :Chemical science 2012
Nicholas A McGrath Ronald T Raines

Diazo compounds, which can be accessed directly from azides by deimidogenation, are shown to be extremely versatile dipoles in 1,3-dipolar cycloaddition reactions with a cyclooctyne. The reactivity of a diazo compound can be much greater or much less than its azide analog, and is enhanced markedly in polar-protic solvents. These reactivities are predictable from frontier molecular orbital energ...

The development of multicomponent reactions (MCRs) designed to produce elaborate biologically active compounds has become an important area of research in organic, combinatorial, and medicinal chemistry. A comparative study of the synthesis of new bis-spiro-oxindolo(pyrrolizidines/pyrrolidines) ring systems by the cycloaddition of azomethine ylides generated by a decarboxylative route from sarc...

Journal: :The Journal of antibiotics 1995
K Nishi M Imuta Y Kimura H Miwa

The synthesis and antibacterial activity of the title compounds having an isoxazolidine ring at the C-2 position are described. These derivatives were synthesized by the 1,3-dipolar cycloaddition reaction of nitrone with 2-vinyl carbapenems. This 1,3-dipolar cycloaddition reaction proceeded regioselectively to give diastereomeric isomers of 2(-isoxazolidin-5-yl)carbapenems. It was ascertained t...

Journal: :international journal of bio-inorganic hybrid nanomaterials 0

the development of multicomponent reactions (mcrs) designed to produce elaborate biologically active compounds has become an important area of research in organic, combinatorial, and medicinal chemistry. a comparative study of the synthesis of new bis-spiro-oxindolo(pyrrolizidines/pyrrolidines) ring systems by the cycloaddition of azomethine ylides generated by a decarboxylative route from sarc...

Journal: :Dalton transactions 2012
Audrey Hospital Clémentine Gibard Christelle Gaulier Lionel Nauton Vincent Théry Malika El-Ghozzi Daniel Avignant Federico Cisnetti Arnaud Gautier

A new strategy was developed for the modification of silver(I) and gold(I) N-heterocyclic carbenes. Azido groups were grafted and used either by copper-catalysed azide-alkyne cycloaddition before metallation or by thermal and "strain-promoted" 1,3-dipolar cycloaddition after metallation to functionalise the metal-NHCs.

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید