Oxazine Derivatives Research Articles

Synthesis, Characterization, and Antibacterial Activity of Novel (1H‐Benzo[d]imidazole‐2‐yl)‐6‐(diethylamino)‐3H‐one‐xanthene, Phenoxazine, and Oxazine

A series of novel (1H‐benzo[d]imidazole‐2‐yl)‐6‐(diethylamino)‐3H‐one‐xanthene, phenoxazine, and oxazine derivatives have been synthesized from 2‐(2′,4′‐dihydroxyphenyl) benzimidazole intermediate. Synthesized compounds 8a, 8b, 8c, 8d are fluorescent in solution, photophysical properties of compounds were studied and results revealed that compounds absorb and emit in UV–visible region with good fluorescence quantum yield. Synthesized compounds are thermally stable up to 300°C. The antibacterial activities of the synthesized compounds were studied by the well‐diffusion method. Escherichia coli (ATTC‐25922), Staphylococcus aureus (ATCC‐25923), Micrococcus (ATCC‐4698), and Bacillus subtilis (ATCC‐55422) were used to investigate the antibacterial activities.

One-pot, expeditious and chromatography-free synthesis of new chromeno[4,3-e][1,3]oxazine derivatives catalyzed by reusable TiO2 nanopowder at room temperature

An expeditious, one-pot, pseudo four-component coupling reaction between 3-hydroxy coumarin, formaldehyde, and amine catalyzed by reusable TiO2 nanopowder in ethanol at room temperature (25–28°C) under stirring condition to synthesize the chromeno[4,3-e][1,3]oxazine derivatives has been described. A wide range of substrate variation, environmentally benign reaction procedure, easy work-up, chromatography free synthesis, and excellent yields with reusability of the catalyst make the methodology highly effective for the synthesis of chromeno[4,3-e][1,3]oxazine derivatives. To the best of our knowledge, this is the first Letter for the synthesis of chromeno[4,3-e][1,3]oxazines using 3-hydroxy coumarin.

Synthesis and Characterization of some New Schiff Bases of 2-Oxonaphtho[2,1-b][1,4]Oxazine

The literature review reveal that [1,4]-oxazine derivatives represent one of the most active classes of compounds possessing wide spectrum of biodynamic activities and use as potent therapeutic agents. In the present work, a series of Schiff base of 2-(2,3-dihydro-2-oxonaphtho[2,1-b][1,4]oxazin-1-yl)acetohydrazide, 5a-5j has been synthesized using 1-aminonaphthalen-2-ol. Various aromatic aldehyde were react with carbohydrazide 4 in the presence of acid to produce the 2-oxonaphtho[2,1-b][1,4]oxazin Schiff base derivatives with good yields. All synthesized compounds were characterized by IR, NMR and Mass spectrometry analysis.

AgI nanoparticles as a remarkable catalyst in the synthesis of (amidoalkyl)naphthol and oxazine derivatives: an eco-friendly approach

AgI nanoparticles were discovered to be an effectual heterogeneous nanocatalyst for the preparation of (amidoalkyl)naphthol and oxazine derivatives under solvent-free conditions. The advantages of the present approach are short reaction times, moderate temperature, premier yields, eco-friendly reaction conditions, simple purification and good reusability of the catalyst.

Synthesis and Characterization of some New Schiff Bases of 2-Oxonaphtho[2,1-b][1,4]Oxazine

The literature review reveal that [1,4]-oxazine derivatives represent one of the most active classes of compounds possessing wide spectrum of biodynamic activities and use as potent therapeutic agents. In the present work, a series of Schiff base of 2-(2,3-dihydro-2-oxonaphtho[2,1-b][1,4]oxazin-1-yl)acetohydrazide, 5a-5j has been synthesized using 1-aminonaphthalen-2-ol. Various aromatic aldehyde were react with carbohydrazide 4 in the presence of acid to produce the 2-oxonaphtho[2,1-b][1,4]oxazin Schiff base derivatives with good yields. All synthesized compounds were characterized by IR, NMR and Mass spectrometry analysis.

Synthesis and photochromic properties of novel spiro[indoline-quinoline]oxazine derivatives

A series of novel spirooxazine derivatives containing nitrogen heterocycles have been synthesized and characterized by 1H NMR, 13C NMR, IR and HRMS in this paper, and the photochromic behaviors of the compounds have been studied in different solutions and the compounds were embedded into a poly(methylmethacrylate) and poly(vinyl butyral) matrix (PMMA, PVB). In solutions, they showed thermochromism and acidichromism. Embedded into polymeric films, the photochromic kinetics of the thermal decoloration of the compounds significantly changed and it was found that the decoloration curves fitted biexponential function. Detailed studies showed that representative compound 1 [1,3,3-trimethyl-6′-piperidino-spiro(indoline-2,3′-[3H]-quinolino[2,1-b][1,4]oxazine)] exhibited high fatigue resistance in poly(methylmethacrylate) and poly(vinyl butyral) matrix.

ChemInform Abstract: Copper‐Catalyzed Intramolecular Electrophilic Carbofunctionalization of Allylic Amides.

AbstractThis intramolecular, endo‐selective oxyarylation and oxyvinylation of allylic amides affords highly functionalized oxazine derivatives.

Design and Synthesis of Two Oxazine Derivatives Using Several Strategies

Several oxazine derivatives have been synthesized; nevertheless, expensive reagents and special conditions are required. Therefore, in this study, two oxazine derivatives (2-chloro-3-{{2-[-(3-chloro-2-oxo-cyclobutyl)-(2,3-dimethoxy-9,10-dihydrostrychnid-10-yl)-amino]-ethyl}-[1,5-dimethyl-4-(1H-naphtho[1,2-e][1,3-oxazin-2-yl)-2-phenyl-2,3-dihydro-1H-pyrazol-3-yl]-amino}-cyclobutanone and 2-chloro-3-{{2-[(3-chloro-2-oxo-cyclobutyl)-(1,7,7-trimethyl-bicyclo[2.2.1]hept-2-yl)-amino]-ethyl}-[1,5-dimethyl-4-(1H-naphtho[1,2-e][1,3]oxazin-2-yl)-2-phenyl-2,3-dihydro-1H-pyrazol-3-yl]-amino}-cyclobutanone) were synthesized using several strategies. The structure of compounds obtained was confirmed by elemental analysis, spectroscopy, and spectrometry data. In conclusion, the methods used offer some advantages such as good yields, simple procedure, low cost, and ease of workup.

Synthesis of anti-2,3-dihydro-1,2,3-trisubstituted-1H-naphth [1,2-e][1,3]oxazine derivatives via multicomponent approach

A series of anti-2,3-dihydro-1,2,3-trisubstituted-1H-naphth [1,2-e][1,3]oxazine derivatives 6 were exclusively obtained in high yields for the first time through multicomponent reactions (MCRs) of 2-naphthol, aromatic aldehydes and electron rich primary amines in ethanol at room temperature using CCl3COOH as catalyst. The same reaction could be conducted effectively in solvent-free medium at 100 °C. The stereochemistry of the two hydrogens connected to C-2 and C-4 (1,3) positions of the oxazine ring are identified as anti-orientation by single crystal XRD, COSY and NOESY analysis.

Prototype nerve-specific near-infrared fluorophores.

Nerve preservation is an important issue during most surgery because accidental transection or injury results in significant morbidity, including numbness, pain, weakness, or paralysis. Currently, nerves are still identified only by gross appearance and anatomical location during surgery, without intraoperative image guidance. Near-infrared (NIR) fluorescent light, in the wavelength range of 650-900 nm, has the potential to provide high-resolution, high-sensitivity, and real-time avoidance of nerve damage, but only if nerve-specific NIR fluorophores can be developed. In this study, we evaluated a series of Oxazine derivatives to highlight various peripheral nerve structures in small and large animals. Among the targeted fluorophores, Oxazine 4 has peak emission near into the NIR, which provided nerve-targeted signal in the brachial plexus and sciatic nerve for up to 12 h after a single intravenous injection. In addition, recurrent laryngeal nerves were successfully identified and highlighted in real time in swine, which could be preserved during the course of thyroid resection. Although optical properties of these agents are not yet optimal, chemical structure analysis provides a basis for improving these prototype nerve-specific NIR fluorophores even further.

Electrochromic Switching and Microkinetic Behaviour of Oxazine Derivatives and Their Applications

AbstractDetailed electrochromic properties including the microkinetic switching behaviour of 2‐nitro‐ (P1) and 2,8‐dinitro‐5a‐[2‐(4‐dimethylaminophenyl)ethylene]‐6,6‐dimethyl‐5a,6‐dihydro‐12H‐indolo[2,1‐b][1,3]benzooxazine (P2) were investigated in both solution and indium tin oxide (ITO) devices with a dual‐wavelength time‐dependent spectra monitoring method for the first time. These two oxazine derivatives displayed improved fatigue resistance and colour reversibility towards electrical stimulation compared with conventional spiropyran derivatives. A new electrochromic mechanism was proposed based on the experimental results and on quantum chemical calculations. Owing to an electron‐withdrawing group para to the nitrogen of the indole fragment, P2 demonstrates better electro‐driven reversibility of structural transformation between ring‐open and ring‐closed isomers than P1.

Abstract P3-03-11: Oxazine derivatives of g- and D- tocotrienols display potent anticancer effects in vivo

Abstract Breast cancer is a multi-stage process which leads to the accumulation of abnormal cells arising from excessive proliferation, lack of apoptosis or a combination of both. Natural compounds such as g-tocotrienol have been shown to selectively inhibit cancer cell growth without harming normal cell viability with little or no adverse side effects. The antiproliferative and apoptotic effects of the tocotrienol isoform, γ-tocotrienol, have been firmly established in various cancer types. However, in vivo studies have provided mixed results, attributed to γ-tocotrienol rapid clearance and low bioavailability. In order to improve anticancer potency and bioavailability in vivo, γ- and Δ-tocotrienol were chemically modified with electrophilic substitution reactions on their chromane ring using Mannich and Lederer-Manasse reactions, resulting in the synthesis of various oxazine derivatives. Several of these oxazine derivatives (compounds 26, 31, 39, 40 and 44) were found to display potent anticancer activity as compared to their parent compounds when tested on +SA mammary cancer cells grown in culture. These in vitro studies were followed up with in vivo studies to determine the anticancer effects of oxazine derivatives on the growth of mammary tumors in mice. Female syngeneic BALB/c mice, 4-6 week old were inoculated with 1×106 +SA mammary tumor cells in the left mammary pad. Once tumor size reached 5mm in diameter, animals were divided into different treatment groups and received an intra-tumoral injection injected of 0-120μg/20μl tocotrienol or its derivative every other day for 11 days. Afterwards, mice were sacrificed, tumors removed and placed in -80°C until further analysis. Results from these studies showed that tumor growth rate was significantly reduced in the oxazine derivative treated animals as compared to the vehicle-treated controls. Western blot analysis of tumor samples showed that the growth inhibitory effects of tocotrienol derivatives was also associated with a significant reduction in phosphorylated (activated) Akt and reductions in cell cycle regulatory proteins cyclin D1 and cyclin dependent kinases (CDK2, CDK4 and CDK6). In addition, oxazine derivative treatment was also associated with a large increase in CDK inhibitors p21 and p27, as compared to tumors obtained from the vehicle-treated control mice. Western blot analysis also showed that tumor from oxazine-derivative treated mice displayed a large reduction in NFκB levels and its downstream gene product COX-2. In summary, oxazine derivatives of tocotrienols display more potent anticancer activity both in vitro and in vivo, as compared to their parent compounds and suggest that these tocotrienol derivatives may provide some benefit as novel anticancer therapeutic agents. This work was supported, in part, by First Tec International Ltd. (Hong Kong), Malaysian Palm oil Council and the Louisiana Cancer Foundation. Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P3-03-11.

Aryl Chalcones as Efficient Precursors for Deriving Oxazine: Solvent-Free Synthesis and Antimicrobial Activities of some Oxazine-2-amines

A series of some oxazine derivatives has been synthesised by fly-ash:H2SO4 catalyzed solvent-free cyclization of aryl chalcones and urea under microwave irradiation. The yields of the oxazines were more than 85%. The synthesised oxazines were characterized by their physical constants, analytical and spectroscopic data. The antimicrobial activities of these oxazines have been studied using Bauer-Kirby method.

ChemInform Abstract: Green Synthesis of Thiazine and Oxazine Derivatives

AbstractReview: 35 refs.

Aryl Chalcones as Efficient Precursors for Deriving Oxazine: Solvent-Free Synthesis and Antimicrobial Activities of some Oxazine-2-amines

A series of some oxazine derivatives has been synthesised by fly-ash:H2SO4 catalyzed solvent-free cyclization of aryl chalcones and urea under microwave irradiation. The yields of the oxazines were more than 85%. The synthesised oxazines were characterized by their physical constants, analytical and spectroscopic data. The antimicrobial activities of these oxazines have been studied using Bauer-Kirby method.

Synthesis and Formylation of Substituted 2-Spiropyrimidin-4-ones and Related Compounds

Treatment of cyclohexanone-2-carboxamide with cyclic ketones provides oxazine derivatives while refluxing in toluene with ammonium acetate and cyclic ketones yields substituted 2-spiropyrimidin-4-ones. Depending on the ratio of reactants, the oxazines and substituted 2-spiropyrimidin-4-ones under Vilsmeier-Haack conditions undergo formylation or an electrophilic rearrangement.

An efficient and green method for the synthesis of [1,3]oxazine derivatives catalyzed by thiamine hydrochloride (VB1) in water

Abstract An efficient and convenient synthesis of 1,3-oxazine derivatives has been achieved by the one-pot, multicomponent condensation of α- or β-naphthol, an aniline and formaldehyde using thiamine hydrochloride (VB1) as a versatile biodegradable and reusable catalyst in water as a universal solvent.

Copper‐Catalyzed Intramolecular Electrophilic Carbofunctionalization of Allylic Amides

This intramolecular, endo-selective oxyarylation and oxyvinylation of allylic amides affords highly functionalized oxazine derivatives.

SYNTHESIS AND FORMYLATION OF SUBSTITUTED 2-SPIROPYRIMIDIN-4-ONES AND RELATED COMPOUNDS

Treatment of cyclohexanone-2-carboxamide with cyclic ketones provides oxazine derivatives while refluxing in toluene with ammonium acetate and cyclic ketones yields substituted 2-spiropyrimidin-4-ones. Depending on the ratio of reactants, the oxazines and substituted 2-spiropyrimidin-4-ones under Vilsmeier-Haack conditions undergo formylation or an electrophilic rearrangement. Authors: V. I. Markov, O. K. Farat, S. A. Varenichenko, E. V. Velikaya, R. I. Zubatyuk, and O. V. Shishkin. English Translation in Chemistry of Heterocyclic Compounds , 2013, 49 (8), pp 1158-1165 http://link.springer.com/article/10.1007/s10593-013-1358-2

Design, Synthesis and Evaluation of Antimicrobial Activity of Novel Oxazine Derivatives using Betti's Protocol

Design, Synthesis and Evaluation of Antimicrobial Activity of Novel Oxazine Derivatives using Betti's Protocol