Results 221 to 230 of about 14,141 (248)

Fluorescence activation with switchable oxazines.

Chemical Communications, 2018
The identification of operating principles to activate fluorescence under the influence of external stimulations is essential to enable the implementation of imaging strategies requiring the spatiotemporal control of emission.
Yang Zhang, Sicheng Tang, Ek Raj Thapaliya, Lorenzo Sansalone, F. Raymo   +4 more
semanticscholar   +1 more source

Nucleophilic Halogenation of Cyclic Nitronates: A General Access to 3-Halo-1,2-Oxazines.

Journal of Organic Chemistry, 2019
In the article, comprehensive studies on the nucleophilic chlorination and bromination of readily available six-membered cyclic nitronates (1,2-oxazine-N-oxides) are reported.
R. S. Malykhin, Aleksandr O. Kokuev, Valentin S. Dorokhov, Y. Nelyubina, V. Tartakovsky, A. Tabolin, S. Ioffe, A. Sukhorukov   +7 more
semanticscholar   +1 more source

Visible-Light Catalytic Photooxygenation of Monoterpene Indole Alkaloids: Access to Spirooxindole-1,3-oxazines.

Chemistry, 2018
Few natural oxindole alkaloids possess an exceptional spiro-[(1,3)oxazinan-3,6'-oxindole] core structure, which results from an unusual oxidative indole rearrangement.
Thorsten von Drathen, F. Hoffmann, M. Brasholz   +2 more
semanticscholar   +1 more source

A Review on Current Synthetic Strategies of Oxazines

Mini-Reviews in Organic Chemistry, 2018
In the past three decades, the heterocyclic oxazine cores have been intensely concerned. Oxazine derivatives are promising vital heterocyclic motifs. They are eminent for their synthetic potential and extensive biological properties.
S. Gaonkar, Vignesh U Nagaraj, Swarnagowri Nayak   +2 more
semanticscholar   +1 more source

Copper-catalyzed pyrrole synthesis from 3,6-dihydro-1,2-oxazines

, 2018
Highly-functionalized pyrroles could be effectively synthesized from 3,6-dihydro-1,2-oxazines using a heterogeneous copper on carbon (Cu/C) under neat heating conditions. Furthermore, the in situ formation of 3,6-dihydro-1,2-oxazines via the hetero Diels–
Naoki Yasukawa, Marina Kuwata, T. Imai, Y. Monguchi, H. Sajiki, Y. Sawama   +5 more
semanticscholar   +1 more source

Rh(II)/Mg(OtBu)2-Catalyzed Tandem One-Pot Synthesis of 1,4-Oxazepines and 1,4-Oxazines from N-Sulfonyl-1,2,3-triazoles and Glycidols.

Organic Letters, 2016
A novel, one-pot route for the synthesis of nonaromatic ring-fused 1,4-oxazepines and 1,4-oxazines has been developed. The reaction features a sequential rhodium(II)-catalyzed reaction of N-sulfonyl-1,2,3-triazoles with glycidols, followed by a ...
Y. O. Ko, Hyun Ji Jeon, Daram Jung, U Bin Kim, Sang-gi Lee   +4 more
semanticscholar   +1 more source

Catalyst-free multi-component cascade C–H-functionalization in water using molecular oxygen: an approach to 1,3-oxazines

, 2017
Herein, catalyst-free 3-component reactions of naphthols, aldehydes, and tetrahydroisoquinolines to synthesize 1,3-oxazines is reported. The reaction is performed in H2O in the presence of O2 as the sole oxidant at 100 °C, which proceeds through the ...
Mohit L. Deb, Choitanya Dev Pegu, Paran J. Borpatra, Prakash J. Saikia, P. Baruah   +4 more
semanticscholar   +1 more source

Dienamine Activation of Diazoenals: Application to the Direct Synthesis of Functionalized 1,4-Oxazines.

Angewandte Chemie, 2016
A novel rhodium-catalyzed dienamine activation of diazoenals resulted in a new class of γ-functionalized donor-acceptor dienamines. The synthetic utility of these dienamines has been demonstrated in a cooperative rhodium(II)/Brønsted acid and gold(I ...
Jagadeesh Kalepu, Sreenivas Katukojvala
semanticscholar   +1 more source

Stereoselective Synthesis and Modelling-Driven Optimisation of Carane-Based Aminodiols and 1,3-Oxazines as Catalysts for the Enantioselective Addition of Diethylzinc to Benzaldehyde.

Chemistry, 2016
The reductive amination of (-)-2-carene-3-aldehyde, prepared in two steps from (-)-perillaldehyde, furnished 2-carene-based allylamines. tert-Butyloxycarbonyl (Boc) or carbobenzyloxy (Cbz) protection of the resulting amines, followed by stereoselective ...
Z. Szakonyi, Árpád Csőr, A. Csámpai, F. Fülöp   +3 more
semanticscholar   +1 more source

Far-Red Emitting Fluorescent Dyes for Optical Nanoscopy: Fluorinated Silicon-Rhodamines (SiRF Dyes) and Phosphorylated Oxazines.

Chemistry, 2015
Far-red emitting fluorescent dyes for optical microscopy, stimulated emission depletion (STED), and ground-state depletion (GSDIM) super-resolution microscopy are presented.
K. Kolmakov, E. Hebisch, T. Wolfram, Lars A Nordwig, C. Wurm, Haisen Ta, V. Westphal, V. Belov, S. Hell   +8 more
semanticscholar   +1 more source