Conventional spectroscopic identification of N-alkylated triazolo-quinazolinones and its antioxidant, solvatochromism studies

Dihydroazolopyrimidines: Past, Present and Perspectives in Synthesis, Green Chemistry and Drug Discovery

Dihydroazolopyrimidines are an important class of heterocycles that are isosteric to natural purines and are therefore of great interest primarily as drug-like molecules. In contrast to the heteroaromatic analogs, synthetic approaches to these compounds were developed much later, and their chemical properties and biological activity have not been studied in detail until recently. In the review, different ways to build dihydroazolopyrimidine systems from different building blocks are described - via the initial formation of a partially hydrogenated pyrimidine ring or an azole ring, as well as a one-pot assembly of azole and azine fragments. Special attention is given to modern approaches: multicomponent reactions, green chemistry, and the use of non-classical activation methods. Information on the chemical properties of dihydroazolopyrimidines and the prospects for their use in the design of drugs of various profiles are also summarized in this review.

Facile synthesis of triazolo/benzazolo[2,1-b]quinazolinone derivatives catalyzed by a new deep eutectic mixture based on glucose, pregabalin and urea

In this study, a novel natural deep eutectic solvent was prepared from glucose, pregabalin, and urea. The prepared solvent was identified using a variety of techniques, including Fourier transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), derivative thermogravimetry (DTG), differential thermal analysis (DTA), and refractive index measurements (RI). The prepared deep eutectic solvent was then utilized for the one-pot synthesis of quinazolinone derivatives. The yields of the product obtained with and without the catalyst were determined, providing insights into the catalytic efficiency of the system. This protocol offers several advantages, including mild reaction conditions, easy reagent preparation, a green process, short reaction times (2-60 min), high yields (80-99%), and a straightforward procedure with the possibility of catalyst reusability.

α-Aminoazoles/azines: key reaction partners for multicomponent reactions

Aromatic α-aminoazaheterocycles are the focus of significant investigations and exploration by researchers owing to their key role in diverse biological and physiological processes. The existence of their derivatives in numerous drugs and alkaloids is due to their heterocyclic nitrogenous nature. Therefore, the synthesis of a structurally diverse range of their derivatives through simple and convenient methods represents a vital field of synthetic organic chemistry. Multicomponent reactions (MCRs) provide a platform to introduce desirable structure diversity and complexity into a molecule in a single operation with a significant reduction in the use of harmful organic waste, and hence have attracted particular attention as an excellent tool to access these derivatives. This review covers the advances made from 2010 to the beginning of 2020 in terms of the utilization of α-aminoazaheterocycles as synthetic precursors in MCRs.

Aminoazole-Based Diversity-Oriented Synthesis of Heterocycles

The comprehensive review contains the analysis of literature data concerning reactions of heterocyclization of aminoazoles and demonstrates the application of these types of transformations in diversity-oriented synthesis. The review is oriented to wide range of chemists working in the field of organic synthesis and both experimental and theoretical studies of nitrogen-containing heterocycles.

Investigation the antioxidant activity of benzo[g]triazoloquinazolines correlated with a DFT study

Previously, a series of 2-phenoxy-benzo[g]triazoloquinazolines 1-16 were synthesized and fully characterized. The antioxidant activity of the target molecules 1-16 was evaluated using three different assays namely 1,1-diphenyl-2-picryl hydrazyl (DPPH) radical scavenging, ferric reduction antioxidant power (FRAP) and reducing power capability (RPC). The results revealed that some benzotriazoloquinazolines showed good activity and have the capacity to scavenge free radicals. In particular, compounds 1 and 14 have shown the highest activity. The butylated hydroxyl toluene (BHT) used as standard agent. Density functional theory was carried out to explain the relative importance of C[bond, double bond]O, C[bond, double bond]S and NH groups on the radical scavenging activity of the target benzotriazoloquinazolines. The finding in present study shows that the active compounds can be used as template for further development of more potent antioxidant agents.

Screening and evaluation of antioxidant activity of some 1,2,4-triazolo[1,5-a]quinazoline derivatives

Aim: The present study was carried out to assess a new series of triazoloquinazolines 1–40 for their antioxidant activities using 1,1-diphenyl-2-picryl hydrazyl radical scavenging, ferric reduction antioxidant power and reducing power capability assays. Results: All triazoloquinazolines 1–40 exhibited antioxidant activity ranged from weak to moderate and high. The obtained findings revealed that the triazoloquinazolines 30, 36 and 38–40 have superiority among all compounds, demonstrating the highest capacity to deplete 1,1-diphenyl-2-picryl hydrazyl and free radicals, in relation to butylated hydroxyl toluene, as a synthetic antioxidant agent. Conclusion: Chemical modifications together with density functional theory study on the targets supplied us with some valuable clarifications about the required properties needed for the target compounds to be more active against free radicals.