Efficient synthesis of some [1,3]-oxazine derivatives in the presence of solid acid nano catalyst based on ferrierite and study on their activity against breast cancer through molecular docking calculation

In this research, the magnetic solid acid nanocatalyst based on ferrierite has been prepared and used as catalyst for the green synthesis of some [1,3]-oxazine derivatives in water at room temperature. The synthesized compounds were obtained in high to excellent yields after short reaction times and the structure of synthesized products were investigated by spectroscopic methods such as: FT-IR, 1H NMR and 13C NMR. The prepared magnetic solid acid catalyst was characterized using XRD, FT-IR, FE-SEM, EDX, elemental mapping, TGA and VSM analysis methods. Magnetic catalyst has easy separation ability, which leads to better and easier recycling. The preparation and synthesis of [1,3]-oxazine derivatives were carried out at room temperature in the presence of M-FER/TEPA/SO3H. Easy workup, green solvent (water) and also short reaction times with high to excellent yield of products, are some of advantageous of presented method. Docking calculations on the structure of the synthesized compounds proved their medicinal properties against breast cancer cells.

Design, synthesis of benzimidazole tethered 3,4-dihydro-2H-benzo[e] [1, 3] oxazines as anticancer agents

A series of novel 3-(1H-benzo[d]imidazol-2-yl)-3,4-dihydro-2H-benzo[e][1,3] oxazine analogues synthesized through a two-step synthetic protocol. The structure of the compounds were established by interpretation 1H NMR, 13C NMR and Mass spectral data recorded after purification. All the title compounds 4a-k were screened for their in vitro anti-cancer activity against two breast cancer cell lines MCF 7 and MDA-MB-231 by using Doxorubicin as standard reference. Compound 4e displayed superior activity against both the cell lines MCF-7 and MDA-MB-231 with IC50 values of 8.60 ± 0.75 and 6.30 ± 0.54 µM respectively, compared to the Doxorubicin IC50 value of 9.11 ± 0.54 and 8.47 ± 0.47 µM. Compound 4i also indicated good activity with IC50 value of 9.85 ± 0.69 μM on par with Doxorubicin against MCF-7 cells. Compound 4g demonstrated best activity on par with standard reference to IC50 value of 8.52 ± 0.62 μM against MDA-MB-231 cell line. And all other compounds demonstrated good to moderate activity compared to Doxorubicin. Docking studies against EGFR showed that all the compounds have very good binding affinities towards the target. The predicted drug-likeness properties of all compounds enable them to be used as therapeutic agents.

Green Synthetic Methods of Oxazine and Thiazine Scaffolds as Promising Medicinal Compounds: A Mini-review

Medical researchers have paid close attention to the green synthesis of oxazine and thiazine derivatives since they provided a lead molecule for the creation of numerous possible bioactive compounds. This review provides more information on green synthesis, which will be very helpful to researchers in creating the most effective, affordable, and clinically significant thiazine and oxazine derivatives that are anticipated to have strong pharmacological effects. This has resulted in the identification of several substances with a wide range of intriguing biological functions. This article's goal is to examine the numerous green chemical processes used to create oxazine and thiazine derivatives and their biological activity. We anticipate that researchers interested in oxazine and thiazine chemicals will find this material to be useful. We anticipate that medicinal chemists looking for new active medicinal components for drug discovery and advance progress will find this review of considerable interest.

Gum arabic-OPO3H2 as a new natural-based green catalyst for the one-pot pseudo-four-component synthesis of naphtho[1,2-e][1,3]oxazines

Gum arabic-OPO3H2 (GA-OPO3H2) as a unique natural-based green catalyst was synthesized by the reaction of phosphorus pentoxide with gum arabic. The structure and properties of the catalyst were studied via several analysis methods such as FT-IR, MAPPING, EDS, SEM, XRD, and TGA. The efficiency of the above-mentioned catalyst was investigated for the synthesis of naphtho-1,3-oxazines via a pseudo-four-component reaction of primary amines, formaldehyde, and 2-naphthol under the solvent-free grinding condition at room temperature using an electrical mortar-heater. The obtained results indicated that GA-OPO3H2 is a highly efficient green catalyst for the synthesis of naphtho[1,2-e][1,3]oxazines with high yields, simple workup, and benign reaction condition.

Antibacterial performance of fully biobased chitosan-grafted-polybenzoxazine films: Elaboration and properties of released material

A fully biobased benzoxazine monomer, V-fa (using vanillin and furfurylamine) was grafted onto chitosan (CS) at different weight ratios (C_XV_Y) using "grafting to" benign Schiff base chemistry. Incorporation of V-fa onto CS increased the tensile strength and improved chemical resistance of the CS-graft-V-fa films. Reversible labile linkages, expansion of CS galleries and leaching out of phenolic species from biobased polymer films led to an improved antibacterial activity against Staphylococcus aureus, which is ∼125 times higher than the bare CS film, V-fa and oligomeric V-fa. The leached out species from films were analyzed extensively by NMR, FTIR, GPC, ABTS and HRMS analysis. Oxidative-stress seems to be responsible for antibacterial activity. Current work illustrates an attractive synthetic approach and the improved antibacterial performance of biobased CS-graft-poly(V-fa) films which may hold as a potential alternative for wound-healing and implant applications in future.

Nano-Fe3O4@walnut shell/Cu(ii) as a highly effective environmentally friendly catalyst for the one-pot pseudo three-component synthesis of 1,3-oxazine derivatives under solvent-free conditions

Fe3O4@walnut shell/Cu(ii) as an eco-friendly bio-based magnetic nano-catalyst was prepared by adding CuCl2 to Fe3O4@walnut shell in alkaline medium. A series of 2-aryl/alkyl-2,3-dihydro-1H-naphtho[1,2-e][1,3]oxazines were synthesized by the one-pot pseudo three-component reaction of β-naphthol, formaldehyde and various amines using nano-Fe3O4@walnut shell/Cu(ii) at 60 °C under solvent-free conditions. The catalyst was removed from the reaction mixture by an external magnet and was reusable several times without any considerable loss of its activity. This protocol has several advantages such as excellent yields, short reaction times, clean and convenient procedure, easy work-up and use of an eco-friendly catalyst.

One-pot solvent-free synthesis of 2,3-dihydro-2-substituted-1H-naphtho[1,2-e][1,3]oxazine derivatives using Fe3O4@nano-cellulose/TiCl as a bio-based and recyclable magnetic nano-catalyst

The present study describes an efficient and environmentally benign protocol for the synthesis of 2,3-dihydro-2-substituted-1H-naphtho[1,2-e][1,3]oxazine derivatives. Synthesis is done by one-pot three-component condensation of 2-naphthol, formaldehyde, and primary amines in the presence of Fe₃O₄@nano-cellulose/TiCl as a bio-based magnetic nano-catalyst under solvent-free conditions at room temperature grinding. This green procedure offers the advantages of high yield, short reaction time, environmental friendliness, easy workup, simple magnetic recovery of the catalyst and its reusability up to ten times without significant loss of catalytic activity. The structure of products was approved by FT-IR, ¹H-NMR, ¹³C-NMR spectroscopy.

Preparing Mn(iii) salen-type Schiff base complexes using 1,3-oxazines obtained by Mannich condensation: towards removing ortho-hydroxyaldehydes

Synthesis of Mn(iii)-salen type Schiff base complexes from 1,3-oxazines obtained from Mannich condensation. This method eliminates the restrictions on the use ofortho-hydroxyaldehydes.

Enzyme and photoredox sequential catalysis for the synthesis of 1,3-oxazine derivatives in one pot

A novel strategy combining visible-light and enzyme catalysis for the synthesis of 1,3-oxazine derivatives is described for the first time.

Microwave-assisted Synthesis and antifungal activity of coumarin[8,7-e][1,3]oxazine derivatives

The synthesis of novel coumarin[8,7-e][1,3]oxazine derivatives through a microwave-assisted three-component one-pot Mannich reaction is described in this study. All the target compounds were evaluated in vitro for their antifungal activity against Botrytis cinerea, Colletotrichum capsici, Alternaria solani, Gibberella zeae, Rhizoctonia solani, and Alternaria mali. The preliminary bioassays showed that 5e, 5m, and 5s exhibited good antifungal activity and the most active compound was 5m with an [Formula: see text] value as low as 2.1 nM against Botrytis cinerea.

Mannich bases in medicinal chemistry and drug design

The biological activity of Mannich bases, a structurally heterogeneous class of chemical compounds that are generated from various substrates through the introduction of an aminomethyl function by means of the Mannich reaction, is surveyed, with emphasis on the relationship between structure and biological activity. The review covers extensively the literature reports that have disclosed Mannich bases as anticancer and cytotoxic agents, or compounds with potential antibacterial and antifungal activity in the last decade. The most relevant studies on the activity of Mannich bases as antimycobacterial agents, antimalarials, or antiviral candidates have been included as well. The review contains also a thorough coverage of anticonvulsant, anti-inflammatory, analgesic and antioxidant activities of Mannich bases. In addition, several minor biological activities of Mannich bases, such as their ability to regulate blood pressure or inhibit platelet aggregation, their antiparasitic and anti-ulcer effects, as well as their use as agents for the treatment of mental disorders have been presented. The review gives in the end a brief overview of the potential of Mannich bases as inhibitors of various enzymes or ligands for several receptors.

Redox-neutral α-oxygenation of amines: reaction development and elucidation of the mechanism

Cyclic secondary amines and 2-hydroxybenzaldehydes or related ketones react to furnish benzo[e][1,3]oxazine structures in generally good yields. This overall redox-neutral amine α-C-H functionalization features a combined reductive N-alkylation/oxidative α-functionalization and is catalyzed by acetic acid. In contrast to previous reports, no external oxidants or metal catalysts are required. Reactions performed under modified conditions lead to an apparent reductive amination and the formation of o-hydroxybenzylamines in a process that involves the oxidation of a second equivalent of amine. A detailed computational study employing density functional theory compares different mechanistic pathways and is used to explain the observed experimental findings. Furthermore, these results also reveal the origin of the catalytic efficiency of acetic acid in these transformations.

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 trans-1,3-diaryl-2-(5-methylisoxazol-3-yl)-2,3-dihydro-1H-naphtho[1,2-e][1,3]oxazines via bismuth(III)-catalyzed one-pot pseudo-four component reaction

An expeditious, straightforward and efficient synthesis of diversely naphtho[1,2-e][1,3]oxazines via one-pot condensation reaction of β- naphthol, 3-amino-5-methylisoxazole and arylaldehydes catalyzed by bismuth(III) trifluoromethanesulfonate is described. The reaction preferentially afforded 1,3-trans oxazines.