114791-08-1Relevant articles and documents
An improved method for the rapid preparation of 2-amino-4,4a-dihydro-4a,7-dimethyl-3H-phenoxazine-3-one, a novel antitumor agent
Tomoda, Akio,Arai, Sadao,Ishida, Ryoji,Shimamoto, Takashi,Ohyashiki, Kazuma
, p. 1057 - 1058 (2001)
A simple and rapid preparation method for a novel antitumor agent, 2-amino-4, 4a-dihydro-4a,7-dimethyl-3H-phenoxazine-3-one (Phx) was described. The procedure included (1) the reaction of bovine hemolysates with 2-amino-5-methylphenol, (2) one-shot denaturation of hemoglobin and proteins by methanol, and removal of the denatured hemoglobin and proteins, (3) concentration of the reaction products, and (4) purification by a Sephadex column. These procedures yielded Phx in 34% yield.
Influence of anions and solvents on distinct coordination chemistry of cobalt and effect of coordination spheres on the biomimetic oxidation of o-aminophenols
Panja, Anangamohan,Jana, Narayan Ch.,Brand?o, Paula
, p. 49 - 61 (2018)
The present work reports the synthesis and structural characterizations of five new cobalt complexes (1–5) resulting from a N3O donor ligand, a Schiff base condensation product of N,N-dimethyldipropylenetriamine and 3-ethoxysalicylaldehyde, and their catalytic activity for the aerobic oxidation of various substrates, namely o-aminophenols and catechol. X-ray structural studies reveal that the Schiff base ligand can bind the metal centre either in the tetradentate fashion using all the available donor sites of the monoanionic deprotonated form (in 2 and 3) or in the tridentate fashion using the zwitterionic form of the Schiff base ligand with pendent quaternary amine nitrogen (in 1 and 4). Additionally, the monoanionic deprotonated ligand can bind the metal centre in the tridentate fashion (in 4 and 5) where the pendent tertiary amine nitrogen is involved in the intramolecular hydrogen bonding. All these adaptabilities associated with this triamine make it appealing candidate for exploration of the coordination chemistry with diverse structures. All complexes except compound 1 are efficient functional models for phenoxazinone synthase, and as expected the availability of labile sites at the first coordination sphere for the substrate, o-aminophenol, binding is the governing factor for higher catalytic activity in 2 and 3. Requisite of the hydrogen bond acceptor centre as well as proton abstraction centre at the second coordination sphere behind the facile oxidation of the substrate were also explored (reactivity of 1 versus 4 and 5). Moreover, the broader catalytic ability of these complexes was examined with substituted aminophenol and catechol as substrates, and the results were assembled and analysed. Furthermore, emphasis was given to get insight into the mechanistic pathway of functioning phenoxazinone synthase activity, well supported by the mass spectral study.
Catalytic oxidative cyclocondensation of o-aminophenols to 2-amino-3H-phenoxazin-3-ones
Giurg, Miroslaw,Piekielska, Katarzyna,Gebala, Magdalena,Ditkowski, Bartosz,Wolanski, Marcin,Peczynska-Czoch, Wanda,Mlochowski, Jacek
, p. 1779 - 1789 (2007)
The catalytic oxidative cyclocondensation of the o-aminophenols 1a-f was investigated. The oxidants used were air/laccase, H2O2/horseradish peroxidase, H2O2/ebselen (3), and TBHP/diphenyl diselenide 4. The products obtained were 2-amino-3H-phenoxazin-3-on
Synthesis, structure and diverse coordination chemistry of cobalt(III) complexes derived from a Schiff base ligand and their biomimetic catalytic oxidation of o-aminophenols
Jana, Narayan Ch.,Patra, Moumita,Brand?o, Paula,Panja, Anangamohan
, p. 23 - 34 (2019)
This paper deals with the syntheses and structural characterizations of four new cobalt(III) compounds (1–4) derived from a N3O donor Schiff base ligand and their catalytic activity towards the aerobic oxidation of o-aminophenols. Both counter
Expansion of the aromatic part of Cinchona alkaloids. Annulation of quinolines with phenoxazine motifs
W?sińska-Ka?wa, Ma?gorzata,Giurg, Miros?aw,Boratyński, Przemys?aw J.,Skar?ewski, Jacek
, p. 308 - 315 (2018)
An oxidative cross-coupling strategy for quinoline ring annulation in Cinchona alkaloids has been developed. Key-reaction optimization by changing oxidants and adjusting the nucleophilicity of the 2-aminophenols led to cupreine and cupreidine expanded with the phenoxazinone unit in 56–75% yield. The stereochemical integrity of the obtained alkaloid structures was confirmed by combined experimental and computed CD and NMR data. The conformational study revealed a fast equilibrium of the three conformers, differing in the orientation of the pyrido[a-3,2]phenoxazine moiety.
A rare flattened tetrahedral Mn(II) salen type complex: Synthesis, crystal structure, biomimetic catalysis and DFT study
Banerjee, Saikat,Ghorai, Pravat,Sarkar, Papiya,Panja, Anangamohan,Saha, Amrita
, (2020)
A new flattened tetrahedral high spin Mn(II) complex (1) has been synthesized using N2O4 donor Schiff base ligand. Complex 1 was characterized by X-ray diffraction and various spectroscopic techniques. For further understanding of el
TEMPO-catalyzed electrochemical dehydrogenative cyclocondensation of: O -aminophenols: Synthesis of aminophenoxazinones as antiproliferative agents
Cai, Yun-Rui,Ji, Su-Hui,Ma, Zhi-Yuan,Shonhe, Chantale,Zhou, Jianmin
supporting information, p. 8566 - 8570 (2021/11/17)
The aminophenoxazinone core is widely prevalent in natural products, dyes and pharmaceutical molecules. We report here a TEMPO-catalyzed electrosynthetic method allowing the dehydrogenative cyclocondensation of o-aminophenols. This mild and sustainable method proceeds in the absence of stoichiometric oxidants and uses an easily available organo-electrocatalyst to access pharmaceutically valuable 2-aminophenoxazinones. Mechanistic studies indicate that the electrochemically generated TEMPO+ enables the oxidative radical homo-dimerization of o-aminophenols. The application of electrosynthesis provides an approach for the synthesis of pseudo-aminophenoxazinone alkaloids with improved structural diversification and bioactivities. This journal is
