Results 1 to 10 of about 1,058 (166)

Iodination of carbohydrate-derived 1,2-oxazines to enantiopure 5-iodo-3,6-dihydro-2H-1,2-oxazines and subsequent palladium-catalyzed cross-coupling reactions [PDF]

Beilstein Journal of Organic Chemistry, 2016
Iodination of carbohydrate-derived 3,6-dihydro-2H-1,2-oxazines of type 3 using iodine and pyridine in DMF furnished 5-iodo-substituted 1,2-oxazine derivatives 4 with high efficacy. The alkenyl iodide moiety of 1,2-oxazine derivatives syn-4 and anti-4 was
Michal Medvecký, Igor Linder, Luise Schefzig, Hans-Ulrich Reissig, Reinhold Zimmer   +4 more
doaj   +8 more sources

[3+3]-Annulation of Cyclic Nitronates with Vinyl Diazoacetates: Diastereoselective Synthesis of Partially Saturated [1,2]Oxazino[2,3-b][1,2]oxazines and Their Base-Promoted Ring Contraction to Pyrrolo[1,2-b][1,2]oxazine Derivatives [PDF]

Molecules, 2023
A rhodium(II)-catalyzed reaction of cyclic nitronates (5,6-dihydro-4H-1,2-oxazine N-oxides) with vinyl diazoacetates proceeds as a [3+3]-annulation producing bicyclic unsaturated nitroso acetals (4a,5,6,7-tetrahydro-2H-[1,2]oxazino[2,3-b][1,2]oxazines ...
Yulia A. Antonova, Yulia V. Nelyubina, Sema L. Ioffe, Andrey A. Tabolin   +3 more
doaj   +2 more sources

Palladium-catalyzed cross coupling reactions of 4-bromo-6H-1,2-oxazines [PDF]

Beilstein Journal of Organic Chemistry, 2009
A number of 4-aryl- and 4-alkynyl-substituted 6H-1,2-oxazines 8 and 9 have been prepared in good yields via cross coupling reactions of halogenated precursors 2, which in turn are easily accessible by bromination of 6H-1,2-oxazines 1. Lewis-acid promoted
Reinhold Zimmer, Elmar Schmidt, Michal Andrä, Marcel-Antoine Duhs, Igor Linder, Hans-Ulrich Reissig   +5 more
doaj   +2 more sources

One-pot synthesis of naphtho[1,2-e][1,3]oxazines in the presence of FNAOSiPAMP*/CuII as an almond shell based nanocatalyst [PDF]

Scientific Reports, 2022
In the present research work, a novel catalyst based on natural material, namely, Fe3O4@nano-almondshell@OSi(CH2)3/NHCH2pyridine/CuII abbreviated (FNAOSiPAMP/CuII) was designed and prepared.
Mina Keihanfar, Bi Bi Fatemeh Mirjalili
doaj   +2 more sources

Towards the Asymmetric Synthesis of 1,2-Oxazines [PDF]

, 2010
The present work dealt with the preparation of some key intermediates and their use for the generation of chemical diversity. In Chapter 2 the synthesis of cycloadducts 2.24 was attempted starting fiom acyl nitroso species 2.2. In Chapter 3 a novel route
Piras, Linda
core   +2 more sources

Novel Synthetic Oxazines Target NF-κB in Colon Cancer In Vitro and Inflammatory Bowel Disease In Vivo. [PDF]

PLoS ONE, 2016
Aberrant activation of nuclear factor kappa B (NF-κB) has been linked with the pathogenesis of several proinflammatory diseases including number of cancers and inflammatory bowel diseases.
Anilkumar C Nirvanappa, Chakrabhavi Dhananjaya Mohan, Shobith Rangappa, Hanumappa Ananda, Alexey Yu Sukhorukov, Muthu K Shanmugam, Mahalingam S Sundaram, Siddaiah Chandra Nayaka, Kesturu S Girish, Arunachalam Chinnathambi, M E Zayed, Sulaiman Ali Alharbi, Gautam Sethi, Basappa, Kanchugarakoppal S Rangappa   +14 more
doaj   +1 more source

One-pot nucleophilic substitution–double click reactions of biazides leading to functionalized bis(1,2,3-triazole) derivatives

Beilstein Journal of Organic Chemistry, 2023
The nucleophilic substitution of benzylic bromides with sodium azide was combined with a subsequent copper-catalyzed (3 + 2) cycloaddition with terminal alkynes.
Hans-Ulrich Reissig, Fei Yu
doaj   +1 more source

Use of Formic Acid as a CO Surrogate for the Reduction of Nitroarenes in the Presence of Dienes: A Two-Step Synthesis of N-Arylpyrroles via 1,2-Oxazines [PDF]

, 2023
Formic acid, activated by acetic anhydride and a base, was employed as a CO surrogate to deoxygenate nitroarenes to nitrosoarenes, a reaction catalyzed by a palladium/phenanthroline complex in the homogeneous phase.
Abdellatif M. A. F., Ferretti F., Galie S., Ragaini F.   +3 more
core   +1 more source

Solid-Phase Synthesis of ɤ-Lactone and 1,2-Oxazine Derivatives and Their Efficient Chiral Analysis. [PDF]

PLoS ONE, 2016
Derivatives of 3-methyl-3,6-dihydro-2H-1,2-oxazine-6-carboxylic acid prepared by regioselective hetero Diels-Alder reaction of arylnitroso compounds with sorbic acid were used for solid-phase synthesis of a library of derivatives that included ...
Sona Krupkova, Gonzalo Pazos Aguete, Leona Kocmanova, Tereza Volna, Martin Grepl, Lucie Novakova, Marvin John Miller, Jan Hlavac   +7 more
doaj   +1 more source

Synthesis of Tetrahydro-1,2-oxazines and Pyrrolidines via Cycloadditions of Donor-Acceptor Cyclobutanes and Nitrosoarenes [PDF]

, 2015
During efforts to expand the scope of Lewis-acid-catalyzed [4+2] cycloaddition between donor–acceptor cyclobutanes and nitrosoarenes, an unexpected formation of pyrrolidine products was discovered when 50 mol-% of MgI2 was used as a Lewis acid.
Allart, Armarego, de Nanteuil, de Nanteuil, Defoin, Gao, Gothelf, Kawano, Kobayashi, Machin, Matsuo, Matsuo, Matsuo, Matsuo, Matsuo, Matsuo, Molander, Negishi, Padwa, Pagenkopf, Parsons, Perrotta, Priewisch, Reissig, Seiser, Shenje, Shimada, Souillart, Stanley, Stevens, Stevens, Still, Taylor, Vemula   +33 more
core   +4 more sources