Synthesis and in-vitro Antioxidant Activity of Novel Schiff Bases and Azetidines Derived from Phenyl Urea Derivatives

Abstract

Objective: The Schiff bases and azetidines are important intermediates used in synthesis of several therapeutics and medicinally contributing molecules. This research was focused on synthesis of Schiff bases and azetidines, characterization and subsequent evaluation of their in-vitro antioxidant potentials. Methods: In this work, the Schiff bases and azetidines were derived from phenyl urea derivatives. They were tested qualitatively for melting point and characterized by TLC, FTIR, 1H-NMR, 13 C-NMR and GCMS for their chemical structures. The Schiff bases and azetidines were screened for in-vitro antioxidant activity by employing hydrogen peroxide free-radical inhibition method. Results: The compounds 1-[(1E)-2-(3-fluorophenyl) ethylidene]-3-(4-ethoxyphenyl) urea and3-chloro-2-(3-fluorophenyl)-N-(4-methoxyphenyl)-4-oxoazetidine-1-carboxamide were derived by nucleophilic addition and cycloaddition reactions and had displayed moderate to significant antioxidant effects compared to ascorbic acid. Thus, medicinally and chemically important Schiff bases and azetidines were synthesized successfully. Conclusion:The present research can be a base to explore further simple and easy means of other synthetic schemes in processing of complex and potent bulk chemicals as well as medicinal agents.

Oxadiazole: A highly versatile scaffold in drug discovery

“…[ 7–14 ] The other heterocycles like pyrimidine, furan, pyrrole, indole, oxadiazole, benzoxazole, azetidine, thiophene, coumarin, benzofuran, pyrazole, quinoline oxazole, quinazoline, pyrimidine, thiazole, quinoline, pyrazole, and isoxazole also possess various pharmacological activities. [ 8,15–30 ]…”

“…[7][8][9][10][11][12][13][14] The other heterocycles like pyrimidine, furan, pyrrole, indole, oxadiazole, benzoxazole, azetidine, thiophene, coumarin, benzofuran, pyrazole, quinoline oxazole, quinazoline, pyrimidine, thiazole, quinoline, pyrazole, and isoxazole also possess various pharmacological activities. [8,[15][16][17][18][19][20][21][22][23][24][25][26][27][28][29][30] The Food and Drug Administration (FDA)-approved drugs in recent years contain biologically active heterocycles in their structures. The drugs like remdesivir (broad-spectrum antiviral drug), [31] avaprinitib (an antitumor drug), [32] pematinib (an anticancer drug used to treat cholangiocarcinoma), [33] remimazolam (sedative drug), [34] and oliceradine (pain medication) [35] approved in 2020 (Figure 1).…”