Synthesis and evaluation of condensed and noncondensed heterocyclic compounds of industrial application

An updated review of fatty acid residue-tethered heterocyclic compounds: synthetic strategies and biological significance

Heterocyclic compounds have been featured as the key building blocks for the development of biologically active molecules. In addition to being derived from renewable raw materials, fatty acids possess a variety of biological properties. The two bioactive ingredients are being combined by many researchers to produce hybrid molecules that have a number of desirable properties. Biological activities and significance of heterocyclic derivatives of fatty acids have been demonstrated in a new class of heterocyclic compounds called heterocyclic fatty acid hybrid derivatives. The significance of heterocyclic-fatty acid hybrid derivatives has been emphasized in numerous research articles over the past few years. In this review, we emphasize the development of synthetic methods and their biological evaluation for heterocyclic fatty acid derivatives. These reports, combined with the upcoming compilation, are expected to serve as comprehensive foundations and references for synthetic, preparative, and applicable methods in medicinal chemistry.

Pd-Catalyzed Carbonylative Synthesis of 4H-Benzo[d][1,3]Oxazin-4-Ones Using Benzene-1,3,5-Triyl Triformate as the CO Source

A facile synthesis of 4H-benzo[d][1,3]oxazin-4-one derivatives by Pd-catalyzed carbonylative cross-coupling between N-(ortho-bromoaryl)amides and benzene-1,3,5-triyl triformate (TFBen) was developed. This procedure does not require the toxic and flammable gas CO as the carbonyl source and tolerates a wide scope of functional groups. Remarkably, 4H-benzo[d][1,3]oxazin-4-ones incorporated to natural products and drugs can be constructed by this method.

Recent investigations into synthesis and pharmacological activities of phenoxy acetamide and its derivatives (chalcone, indole and quinoline) as possible therapeutic candidates

Medicinal chemistry can rightfully be regarded as a cornerstone in the public health of our modern society that combines chemistry and pharmacology with the aim of designing and developing new pharmaceutical compounds. For this purpose, many chemical techniques as well as new computational chemistry applications are used to study the utilization of drugs and their biological effects. In the biological interface, medicinal chemistry constitutes a group of interdisciplinary sciences, as well as controlling its organic, physical and computational pillars. Therefore, medicinal chemists working to design an integrated and developing system that portends an era of novel and safe tailored drugs either by synthesizing new pharmaceuticals or to improving the processes by which existing pharmaceuticals are made. It includes researching the effects of synthetic, semi-synthetic and natural biologically active substances based on molecular interactions in terms of molecular structure with triggered functional groups or the specific physicochemical properties. The present work focuses on the literature survey of chemical diversity of phenoxy acetamide and its derivatives (Chalcone, Indole and Quinoline) in the molecular framework in order to get complete information regarding pharmacologically interesting compounds of widely different composition. From a biological and industrial point of view, this literature review may provide an opportunity for the chemists to design new derivatives of phenoxy acetamide and its derivatives that proved to be the successful agent in view of safety and efficacy to enhance life quality.

Photoinduced oxidation of an indole derivative: 2-(1'H-indol-2'-yl)-[1,5]naphthyridine

The UV-induced oxidation of 2-(1'H-indol-2'-yl)-[1,5]naphthyridine acetonitrile solution in the presence of air leads to the formation of 2-(1,5-naphthyridin-2-yl)-4H-3,1-benzoxazin-4-one as a major product and N-(2-formylphenyl)-1,5-naphthyridine-2-carboxamide as a minor one. The probable reaction mechanisms are different for the two photoproducts and may involve both the reaction with singlet oxygen generated by the excited substrate or the reaction of the excited substrate with the ground state oxygen molecule. Electronic absorption and IR spectra indicate that both photoproducts are formed as mixtures of syn and anti-rotameric forms. The obtained results indicate an efficient and easy method for the synthesis of molecules with a benzoxazinone structure.

Gold-catalyzed formal [4π + 2π]-cycloadditions of propiolate derivatives with unactivated nitriles

Gold-catalyzed hetero-[4π + 2π]-cycloadditions of tert-butyl propiolates with unactivated nitriles are described. This new finding enables a one-pot gold-catalyzed synthesis of highly substituted pyridines.

Gold-catalyzed hetero-[4π + 2π]-cycloadditions of tert-butyl propiolates with unactivated nitriles are described; the resulting 6H-1,3-oxazin-6-ones are not easily accessible via conventional methods. This new finding enables a one-pot gold-catalyzed synthesis of highly substituted pyridines through sequential gold-catalyzed reactions of tert-butyl propiolates with nitriles, and then with electron-deficient alkynes in the same solvent. The utility of these [4 + 2]-cycloadditions is further expanded with various aldehydes, ketones and 2-phenyloxetane, yielding satisfactory yields of cycloadducts.

One-pot synthesis of 2-substituted 4H-3,1-benzoxazin-4-one derivatives under mild conditions using iminium cation from cyanuric chloride/dimethylformamide as a cyclizing agent

BACKGROUND

The derivatives of 2-substituted 4H-3,1-benzoxazin-4-one belong to a significant category of heterocyclic compounds, which have shown a wide spectrum of medical and industrial applications.

RESULTS

A new and effective one-pot method for the synthesis of 2-substituted 4H-3,1-benzoxazin-4-one derivatives is described in this paper. By using the iminium cation from a mixture of cyanuric chloride and dimethylformamide as a cyclizing agent, a series of 2-substituted 4H-3,1-benzoxazin-4-one derivatives was synthesized in high yield under mild conditions and simple workup.

CONCLUSIONS

The iminium cation from a mixture of cyanuric chloride and N,N-dimethylformamide is an effective cyclizing agent for the room temperature one-pot synthesis of 2-substituted 4H-3,1-benzoxazin-4-one derivatives in high yields through a cyclodehydration reaction. Furthermore, the method was performed under mild conditions characterized by simplified pathways and workup, minimized energy, and fewer reaction steps, compared with the previous methods. The proposed method, which is a simpler alternative than the published methods, is applicable for the synthesis of other 2-substituted 4H-3,1-benzoxazin-4-one derivatives.