112 Results Found

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.

4-Acyl-1H-pyrrole-2,3-diones fused at [e]-side with a heterocyclic moiety are suitable platforms for the development of a hetero-Diels–Alder-reaction-based, diversity-oriented approaches to series of skeletally diverse heterocycles. These platf...

A one-pot route to 2-alkyl and 2-aryl-4H-benzo[d][1,3]oxazin-4-ones (also known as 4H-3,1-benzoxazin-4-ones) has been developed and studied. The method involves the reaction of aryl-substituted anthranilic acids with orthoesters in ethanol catalyzed...

A rhodium(II)-catalyzed reaction of cyclic nitronates (5,6-dihydro-4H-1,2-oxazine N-oxides) with vinyl diazoacetates proceeds as a [3+3]-annulation producing bicyclic unsaturated nitroso acetals (4a,5,6,7-tetrahydro-2H-[1,2]oxazino[2,3-b][1,2]oxazine...

A copper catalyzed tandem CuAAC/ring cleavage/[4+2] annulation reaction of terminal ynones, sulfonyl azides, and imines has been developed to synthesize the functionalized oxazines under mild conditions. Particularly, the intermediate N-sulfonyl acyl...

Introduction: According to research data, 1,3-oxazines are pharmacologically active substances, as well as the substrates for the synthesis of heterocyclic and acyclic compounds. However, bis(1,3-oxazin-6-one) derivatives are little studied class of...

The 11a,12-dihydrobenzo[b]benzo[5,6][1,4]oxazino[2,3-e][1,4]oxazine heterocyclic system has been used in the construction of heteropropellanes, which attracted much attention not only on the possible modification of drugs, but also for novel material...

The behavior of star-shaped six-arm poly-2-alkyl-2-oxazines and poly-2-alkyl-2-oxazolines in aqueous solutions on heating was studied by light scattering, turbidimetry and microcalorimetry. The core of stars was hexaaza [2₆] orthoparacyclophane and t...

Reaction of allyl bromide (Z)-1 and (Z)-2 with N-substituted hydroxylamine hydrochlorides in presence of tert-butoxide in tert-butanol at reflux provides a short and effective route to [1,2]isoxazolidin-5-ones 3 and [1,2]oxazin-6-ones 4.

The water–salt solutions of star-shaped six-arm poly-2-alkyl-2-oxazines and poly-2-alkyl-2-oxazolines were studied by light scattering and turbidimetry. The core was hexaaza[2₆]orthoparacyclophane and the arms were poly-2-ethyl-2-oxazine, poly-2-isop...

Nuclear factor kappa B (NF–κB) is a potential therapeutic target in breast cancer. In the current study, a new class of oxazine– and piperazine–linked pyrimidines was developed as inhibitors of NF–κB, overcoming th...

A series of titanium and vanadium complexes with oxazoline 2-(4,5-dihydro-1,3-oxazol-2-yl)phenol (L1), 2-(4-methyl-4,5-dihydro-1,3-oxazol-2-yl)phenol (L2), and oxazine 2-(5,6-dihydro-4H-1,3-oxazin-2-yl)phenol (L3) ligands were synthesized, and their...

The use of water as a nucleophile in catalytic asymmetric reactions remains a significant challenge, primarily due to its intrinsically low nucleophilicity and small size, which make precise control over both reactivity and stereoselectivity particul...

Background/Objectives: Glioblastoma (GBM) is the most aggressive primary malignant brain tumor in adults, characterized by highly infiltrative growth and poorly defined margins that hinder complete surgical resection. Fluorescence-guided surgery (FGS...

The article presents fabrication and luminescent properties of poly(methyl methacrylate) (PMMA) fiber doped by Oxazine 170 perchlorate. The bright fluorescence of polymeric fiber (at molar fluorescent organic dye concentration 4.3 × 10⁻⁵) was charact...

The reaction of 2,5-dimethylfuran (DMF) with two equivalents of α-nitrosostyrene (NS) leading to a tricyclic 1,2-oxazine nitrone (TON) has been examined theoretically at the ωB97X-D/6-311G(d,p) computational level. In this case, the domin...

N-cinnamoyl anthranilic acids are synthesized in a single, eco-friendly step by condensing various cinnamic acids with free 2-aminobenzoic acid derivatives using the mixed carbonic anhydride method. Subsequently, converting the resulting N-cinnamoyl...

A small library of 1H-benzo[4,5]imidazo[1,2-c][1,3]oxazin-1-one derivatives was prepared in good to excellent yields, involving a Ag₂CO₃/TFA-catalyzed intramolecular oxacyclization of N-Boc-2-alkynylbenzimidazole substrates. In all experiments, the 6...

A tailored series of coumarin-based ferrocenyl 1,3-oxazine hybrid compounds was synthesized and investigated for potential antiparasitic activity, drawing inspiration from the established biological efficacy of the constituent chemical motifs. The st...

The synthesis, characterization, and anticancer properties of three imine-type compounds 1–3 and an unexpected oxazine derivative 4 are presented. The reaction of p-dimethylaminobenzaldehyde or m-nitrobenzaldehyde with hydroxylamine hydrochlori...

Studies show that compounds such as 1,3-oxazine-6-ones are promising starting reagents that allow us to obtain various acyclic and heteroaromatic systems. These substances demonstrate a wide range of biological activity. Meanwhile, it is known that d...

A new type of benzoxazine resin has been synthesized using a natural phenol source, guaiacol, and a biomass amines, furfuramine. The synthesis conditions were optimized; when the reaction molar ratio of guaiacol, furfuramine, and polyformaldehyde was...

The growing interest in the chemistry of unsaturated ring-fused 1,3-heterocycles, in this particular case 1,3-oxazines, arise in part from their versatile pharmacological applications. In the present article, the evaluation of the in vitro and ex viv...

Star-shaped six-arm poly-2-alkyl-2-oxazine and poly-2-alkyl-2-oxazoline with hexaaza [2₆]orthoparacyclophane derivative core were synthesized successfully using cationic ring-opening polymerization. Conformational behavior of prepared polymer stars w...

The reaction of 8-(4-bromobenzoyl)-3,4-dihydro-1H-pyrrolo[2,1-c][1,4]oxazine-1,6,7-trione with benzylamine in acetonitrile at room temperature afforded a good yield of (Z)-1-benzyl-5-(4-bromophenyl)-5-hydroxy-4-(2-oxomorpholin-3-ylidene)pyrrolidine-2...

The reaction of 3-cyclohexyl-2-(cyclohexylimino)-6-(4-ethoxyphenyl)-5-(4-methyl-3-oxo-3,4-dihydroquinoxalin-2-yl)-2,3-dihydro-4H-1,3-oxazin-4-one with ammonium acetate afforded 3-(1-cyclohexyl-2-(cyclohexylamino)-4-(4-ethoxyphenyl)-6-oxo-1,6-dihydrop...

The reaction of 4,4-dimethyl-8-(4-methylbenzoyl)-3,4-dihydro-1H-pyrrolo[2,1-c][1,4]oxazine-1,6,7-trione with thioacetamide in a 1:1 ratio when refluxed in dichloromethane gives (4S*,10aS*,11S*)-4-hydroxy-2,7,7-trimethyl-11-(4-methylbenzoyl)-7,8-dihyd...

This paper presents an investigation of the modification of natural oxazines to traditional bisphenol A benzoxazines. Eugenol was reacted with furfurylamine to synthesize a new type of benzoxazine (eugenol–furfurylamine benzoxazine), with a yie...

Currently, 1-amidoalkyl-2-naphthol derivatives are of increasing interest due to their biological activities and further use in the preparation of other important bioactive molecules, such as aminoalkyl naphthols and oxazines. The synthesis of 1-amid...

A simple and convenient synthesis of (–)-6,7-dimethoxy-1,2,3,4-tetrahydroisoquinoline-1-carboxylic acid is described, applying a combination of two synthetic methods: the Petasis reaction and Pomeranz–Fritsch–Bobbitt cyclization. Th...

In this study, a quantitative analysis of nitrate in aqueous solution was performed through the combination of an oxazine170 perchlorate–ethyl cellulose (O17-EC) membrane with aluminum-containing compounds. Aluminum of Devarda’s alloy (DA...

As one kind of “smart” material, thermogelling polymers find applications in biofabrication, drug delivery and regenerative medicine. In this work, we report a thermosensitive poly(2-oxazoline)/poly(2-oxazine) based diblock copolymer comprising therm...

Capsicum annuum, commonly known as pepper, is a widely cultivated crop valued for its nutritional and economic significance. Among its varieties, the small red bell pepper, locally known as “pimienta palmera”, is a unique cultivar from La...

In this study, a novel bio-based oxazine resin was synthesized through the reaction of naturally renewable materials: cardanol and furfurylamine. The molecular structure of the target product was confirmed via comprehensive characterization technique...

The title compound, (Z)-4-(carbomethoxymethylene)-2-(4-fluorophenyl)-4H-benzo[d][1,3]oxazine, was synthesized in 68% isolated yield by palladium-catalyzed oxidative cyclization-methoxycarbonylation of 4-fluoro-N-(2-((trimethylsilyl)ethynyl)phenyl)ben...

This work describes the synthesis of 3-hydroxy-3,4-dihydropyrido[2,1-c][1,4]oxazine-1,8-diones, their tautomerism, and reactivity towards binucleophiles. These molecules are novel and convenient building-blocks for the direct construction of biologic...

Peniciadametizine A (1); a new dithiodiketopiperazine derivative possessing a unique spiro[furan-2,7'-pyrazino[1,2-b][1,2]oxazine] skeleton, together with a highly oxygenated new analogue, peniciadametizine B (2); as well as two known compounds, bras...

A new tetracyclic morpholine-fused[5,1-c]-triazole, (4aS,5S,6aR,10aR,10bR)-5-methoxy-9,9-dimethyl-4a,5,6a,7,10a,10b-hexahydro-12H-[1,3]dioxino[4′,5′:5,6]pyrano[4,3-b][1,2,3]triazolo[1,5-d][1,4]oxazine, was synthesized via a five-step sequ...

Naphtho[1,8-de][1,2]oxazin-4-ol and its acyl or benzyl derivatives ring open to various 2,8-dihydroxy-1-naphthonitriles, which, through (de)protection protocols and reduction, afford the target (E)-2-hydroxy-8-methoxy-1-naphthaldehyde. This was conve...

An efficient asymmetric synthesis of GlaxoSmithKline’s potent PDE4 inhibitor was accomplished in eight steps from a catechol-derived nitroalkene. The key intermediate (3-acyloxymethyl-substituted 1,2-oxazine) was prepared in a straightforward m...

Cyclization of hydrazones derived from 2-acetyl-1-naphthol and 1-acetyl-2-naphthol with triphosgene gave naphtho[1,2-e]-1,3-oxazines, naphtho[2,1-e]-1,3-oxazines or their spiro dimers depending on the molar ratio of triphosgene used for the cyclization.

In this study, 2-(aminomethyl)phenol and its derivatives, the reactants for 2-substituted 1,3-benzoxazines, are synthesized by HCl hydrolysis from the typical benzoxazines. The phenol/aniline-based mono-oxazine benzoxazine, PH-a, and the bisphenol A/...

3,4-dihydro-3-phenyl-2H-1,3-benzoxazines derived from phenol-, resorcinol-, and phloroglucinol give monomers with one, two, and three oxazine units at a single benzene ring, respectively. Aside from the synthesis and characterization of such multifun...

Some novel hydrazone derivatives 6a–o were synthesized from the key intermediate 4-Chloro-N-(2-hydrazinocarbonyl-phenyl)-benzamide 5 and characterized using IR, ¹H-NMR, ¹³C-NMR, mass spectroscopy and elemental analysis. The inhibitory potential again...

The reaction of pyridines with trifluoroacetylated acetylenes was investigated. It was found that the reaction of various pyridines with two molecules of CF₃CO-acetylenes proceeds under mild metal-free conditions. As a result, efficient stereoselecti...

In this study, we used oxazinethione as a perfect precursor to synthesize new pyrimidine and pyrazole derivatives with potent biological activities. Biological activities were determined for all compounds against A. flavus, E. coli, S. aureus, and F....

The reaction of 3-benzoylpyrrolo[2,1-c][1,4]benzoxazin-1,2,4-trione with N-(4-bromophenyl)-1-(4-methoxyphenyl)methanimine under thermolytical conditions afforded 4-benzoyl-2-(4-bromophenyl)-1-(4-methoxyphenyl)-1,2-dihydropyrimidino[4,3-c][1,4]benzoxa...

The reductive cyclization of different organic nitro compounds by carbon monoxide, catalyzed by transition metal complexes, is a very efficient and clean strategy for the synthesis of many N-heterocycles. However, it requires the use of autoclaves an...

The reductive cyclization of different organic nitro compounds by carbon monoxide, catalyzed by transition metal complexes, is a very efficient and clean strategy for the synthesis of many N-heterocycles. However, its use requires the use of autoclav...

A new alkaloid, 2-(furan-2-yl)-6-(2S,3S,4-trihydroxybutyl)pyrazine (1), along with 12 known compounds, 2-(furan-2-yl)-5-(2S,3S,4-trihydroxybutyl)pyrazine (2), (S)-4-isobutyl-3-oxo-3,4-dihydro-1H-pyrrolo[2,1-c][1,4]oxazine-6-carbaldehyde (3), (S)-4...