Design and Synthesis of Heterocyclic Compounds Containing a Benzothiazole Nucleus and Study of Their Effectiveness as Antioxidants and Their Biological Applications

Wissam, M. R. Al-Joboury

Authors

Wissam, M. R. Al-Joboury Department of Medical Laboratory Techniques, Al-Haeija Technical Institute, Northern Technical University

Keywords:

Antioxidant, pyrimidine, Schiff bases, Biological Evaluation, 2-aminobenzothazol

Abstract

The compounds (W2) (6-(5-fluorothiophen-2-yl)-4-(quinolin-6-yl)pyrimidin-2(1H)-one) in this paper were previously made from α, β unsaturated carbonyl compounds known as chalcones. These compounds are typically made by reacting 6-quinolinearboxaldyde with 1-(5-fluorothiophen-2-yl)ethan-1-one. Following their preparation and purification, appropriate measurements of their physical, chemical, and spectroscopic characteristics were undertaken in order to get chalcones that interacted with urea under established chemical circumstances to produce the necessary pyrimidinone molecule (W2). Using glacial acetic acid as a catalyst in 100% ethanol, pyrimidine compounds interacted with substituted 2-aminobenzothazol compounds to produce novel Schiff's bases (w6–8). IR, 1H-NMR, and certain physical data were used to determine the structures of the synthesized compounds. The disk diffusion assay technique was used to investigate the antibacterial activity in vitro against Gram-positive and gram negative microorganisms. When compared to standard medications, the minimum inhibitory concentration (MIC) of thiazolidine derivatives was shown to be superior to the growth of both gram-positive and gram-negative bacteria. The DPPH technique was used to assess the antioxidant activity of produced compounds using a reference medication. The study's findings showed that, among the compounds evaluated for antioxidant activity, W6 and W8 showed promising antioxidant activity with IC50 values of 3.2µM and 27.30µM, respectively, whereas ascorbic acid, the reference component, had a value of 29.2µM. Compared to conventional ascorbic acid, compounds (W6 and W7) showed remarkable DPPH radical scavenging activity, according to the antioxidant screening results. These findings could potentially offer some important direction for the creation of novel antioxidants.

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