Synthesis and Antimicrobial Activity of some Ester Functionalized Isoxazoles incorporating Anthracene Moieties via Nucleophilic Substitution Reaction

• Published in: Zanco journal of medical sciences Vol. 27; no. 2; pp. 213 - 226
• Main Authors: M. Ahmed, Sarbast, Omer Ahmed, Hewa, H. S. Hussain, Faiq, Sardar Abdulrahman, Hayman, A. Qader, Hemn
• Format: Journal Article
• Language: English
• Published: Hawler Medical University 01.09.2023
• Subjects: 3-dipolar cycloaddition; antimicrobial activity; ester-functionalized isoxazole; nitrile oxide
• ISSN: 1995-5588; 1995-5596
• DOI: 10.15218/zjms.2023.024

Background and objective: Five-membered heterocycle compounds having single oxygen and nitrogen atom at adjacent positions are known as isoxazoles. Isoxazole compounds have a broad range of biological activities and therapeutic value. In view of a strategic design of antimicrobial compounds, several new ester-functionalized isoxazoles were synthesized and characterized. Methods: A regioselective isoxazole incorporating an anthracene moiety was adducted via an effective 1,3-dipolar cycloaddition between anthracene nitrile oxide and propargyl bromide as a dipolarophile. Results: Synthesized isoxazole 4 underwent nucleophilic substitution reaction to produce unprecedented ester-functionalized isoxazoles 6a-j, by condensation with equimolar amounts of different generated in situ sodium carboxylate upon dissolving in acetonitrile with refluxing. The chemical structure of all target compounds was proved by (FT-IR, 1H-NMR, and APT13C-NMR) techniques and their antibacterial and antifungal activities was evaluated. Conclusion: Allnewly synthesizedcompounds6 a-j have been obtained in good yields after purification by column chromatography. They showed significant antibacterial and antifungal activity after screening against two bacterial strains, Escherichia coli and Staphylococcus aureus and a fungi strain, Candida albicans, using disc diffusion method.