Results 41 to 50 of about 7,946 (266)

Carbohydrate-auxiliary assisted preparation of enantiopure 1,2-oxazine derivatives and aminopolyols

Beilstein Journal of Organic Chemistry, 2012
An approach to enantiopure hydroxylated 2H-1,2-oxazine derivatives is presented utilizing the [3 + 3] cyclisation of lithiated alkoxyallenes and an L-erythrose-derived N-glycosyl nitrone as precursors.
Marcin Jasiński, Dieter Lentz, Hans-Ulrich Reissig   +2 more
doaj   +1 more source

Synthesis of New 1,3-Disubstituted-2,3-dihydro-1H-naphth[1,2e][1,3]oxazines

Molecules, 2007
1,3-Disubstituted-2,3-dihydro-1H-naphth[1,2-e][1,3]oxazines were prepared through the ring-closurereactions of the aminobenzylnaphthols with substituted aryl-andheteroarylaldehydes.
Adem Köycü, Emel Pelit, Zuhal Turgut
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   +3 more sources

Modular synthesis and transition metal-free alkynylation/alkenylation of Castagnoli–Cushmanderived N,O- and N,S-heterocyclic vinyl chlorides [PDF]

, 2020
A modular and functional group-tolerant protocol for the transition metal-free coupling of novel N,O- and N,S-heterocyclic vinyl chlorides with terminal acetylenes and styrenes has been developed, leading to the epimerization-free synthesis of fully ...
Beng, Timothy K., Farah, Abdikani Omar, Shearer, Victoria   +2 more
core   +2 more sources

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

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

PLoS ONE, 2017
[This corrects the article DOI: 10.1371/journal.pone.0163209.].
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

Predicting the UV–vis spectra of oxazine dyes [PDF]

Beilstein Journal of Organic Chemistry, 2011
In the current work we have investigated the ability of time-dependent density functional theory (TD-DFT) to predict the absorption spectra of a series of oxazine dyes and the effect of solvent on the accuracy of these predictions. Based on the results of this study, it is clear that for the series of oxazine dyes an accurate prediction of the ...
Fleming, Scott, Mills, Andrew, Tuttle, Tell   +2 more
openaire   +5 more sources

Azirinium ylides from α-diazoketones and 2H-azirines on the route to 2H-1,4-oxazines: three-membered ring opening vs 1,5-cyclization

Beilstein Journal of Organic Chemistry, 2015
Strained azirinium ylides derived from 2H-azirines and α-diazoketones under Rh(II)-catalysis can undergo either irreversible ring opening across the N–C2 bond to 2-azabuta-1,3-dienes that further cyclize to 2H-1,4-oxazines or reversibly undergo a 1,5 ...
Nikolai V. Rostovskii, Mikhail S. Novikov, Alexander F. Khlebnikov, Galina L. Starova, Margarita S. Avdontseva   +4 more
doaj   +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

Fused Nitrogen Bridgehead N,O‐Acetals as Versatile Scaffolds: Synthetic Strategies, Mechanism and Applications

Chemistry – A European Journal, EarlyView.
Fused nitrogen‐bridgehead N,O‐acetals receive specific emphasis as pivotal scaffolds due to their significant role in the bioactivity of medicinally relevant molecules. Significant approaches have been reported on their role as key synthetic building blocks/motifs in the construction of complex organic molecules and their utility as chiral auxiliaries ...
Alexis D. Kouvelas, Michael G. Kallitsakis, Ioannis N. Lykakis   +2 more
wiley   +1 more source