Results 31 to 40 of about 2,492 (186)

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

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

Chemical reactivity of ethyl 4-(1-ethyl-1,2-dihydro-4-hydroxy-2-oxoquinolin-3-yl)-2,4-dioxobutanoate towards some nucleophilic reagents

Journal of the Turkish Chemical Society, Section A: Chemistry, 2016
A novel series of heterocyclic systems linked with quinolin-2-one was efficiently synthesized from reaction of ethyl 4-(1-ethyl-1,2-dihydro-4-hydroxy-2-oxoquinolin-3-yl) -2,4-dioxobutanoate (1) with a variety of nitrogen and/or carbon nucleophiles.
Hany Hassanin, Magdi A. Ibrahim, Shimaa Badran   +2 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

1,2,3-Triazole-4(5)-amines – Convenient Synthetic Blocks for the Construction of Triazolo-Annulated Heterocycles

Журнал органічної та фармацевтичної хімії, 2022
Aim. To analyze and summarize the synthetic potential of 1,2,3-triazole-4(5)-amines as efficient building blocks in the synthesis of triazolo-annulated pyridine, azine and azepine systems. Results and discussion.
Natalia O. Syrota, Sergiy V. Kemskiy, Lesya M. Saliyeva, Mykhailo V. Vovk   +3 more
doaj   +1 more source

Reductive Cleavage of 1,2-Oxazines Promoted by Zinc and Ammonium Chloride; Mild One Pot Preparation of γ-Hydroxy Ketones

E-Journal of Chemistry, 2012
A facile method for a mild single pot reductive cleavage of 1,2-oxazines to γ-hydroxy ketones was developed using zinc and aqueous ammonium chloride as the reagent in methanol.
P. Sunil Kumar, K. M. Lokanatha Rai
doaj   +1 more source

Discovery of C-3 Tethered 2-oxo-benzo[1,4]oxazines as Potent Antioxidants: Bio-Inspired Based Design, Synthesis, Biological Evaluation, Cytotoxic, and in Silico Molecular Docking Studies

Frontiers in Chemistry, 2018
The discovery of C-3 tethered 2-oxo-benzo[1,4]oxazines as potent antioxidants is disclosed. All the analogs 20a-20ab have been synthesized via “on water” ultrasound-assisted irradiation conditions in excellent yields (upto 98%).
Vashundhra Sharma, Pradeep K. Jaiswal, Mukesh Saran, Dharmendra Kumar Yadav, Saloni, Manas Mathur, Ajit K. Swami, Sanjeev Misra, Mi-hyun Kim, Sandeep Chaudhary   +9 more
doaj   +1 more source

Synthesis of 2-substituted benzimidazole, coumarin, benzo[b][1,4]oxazin and dihydropyrimidinone derivatives using core-shell structured Fe3O4@SiO2-ZnCl2 nanoparticles as an effective catalyst

Results in Chemistry, 2020
In this paper, a magnetic nanocatalyst of Fe3O4@SiO2-ZnCl2 has been used which enhances the synthesis of benzimidazoles, coumarins, benzoxazines and dihydropyrimidinones. To begin with, 2-substituted benzimidazoles have been synthesized in proper to high
Saba Rahimi, Ebrahim Soleimani
doaj   +1 more source

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