Research Article

Synthesis, Antibacterial, Antioxidant, and In Silico Evaluation of New Sulfamethoxazole-Based Schiff Base and Azo Derivatives

Volume: 2026 Number: 2 September 10, 2026

Synthesis, Antibacterial, Antioxidant, and In Silico Evaluation of New Sulfamethoxazole-Based Schiff Base and Azo Derivatives

Abstract

This research involved the preparation of a new Schiff base derivative (1) and azo derivatives (2–7) based on sulfamethoxazole through the coupling reaction of diazonium salt with various phenols. The yields were very high, ranging from 81% to 91%. The synthesis of these compounds was characterized using various techniques such as FT-IR, 1H-NMR and 13C-NMR. The antioxidant activity of these com-pounds was investigated utilizing the DPPH radical scavenging assay. The findings indicated that all compounds possessed antioxidant activity that increased proportionally with increasing concentration, particularly compounds 6 and 7, possibly due to the presence of hydroxyl groups in their structures. The biological activity of the synthesized derivatives1-7 as antibacterial agents was also investigated through in silico studies, including ADME and molecular docking, and in vitro studies, including the diffu-sion inhibition method. The ADME study indicated that several synthesized derivatives exhibited physi-cochemical and pharmacokinetic properties consistent with Lipinski's criteria. The results of molecular docking with the dihydropteroate synthase protein (DHPS) showed that these compounds are capable of binding to the protein's active site through the formation of hydrogen and hydrophobic interactions with a docking score ranging between −5.279and −3.638kcal/mol. As for the biological activity test, it was carried out using four types of Gram-negative and Gram-positive bacteria, and the results showed that the compounds have varying activity, ranging from moderate to strong or no inhibition against some bacteria, while showing broad inhibition capacity against all types of bacteria used for compound 5. The results show that the synthesized sulfamethoxazole-based compounds (1-7) are attractive can-didates for the development of novel antioxidant and antibacterial drugs.

Keywords

Thanks

The authors thank the Chemistry Department / College of Science / University of Baghdad and also thank everyone who helped prepare the research.

References

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Details

Primary Language

English

Subjects

Organic Chemistry (Other)

Journal Section

Research Article

Publication Date

September 10, 2026

Submission Date

May 9, 2026

Acceptance Date

July 25, 2026

Published in Issue

Year 2026 Volume: 2026 Number: 2

APA
Ahmed, K., Al-Adhami, H., Sallal, Z., & Al-Khuzaie, M. (2026). Synthesis, Antibacterial, Antioxidant, and In Silico Evaluation of New Sulfamethoxazole-Based Schiff Base and Azo Derivatives. Journal of the Turkish Chemical Society Section A: Chemistry, 2026(2), 1-12. https://doi.org/10.18596/jotcsa.1947271
AMA
1.Ahmed K, Al-Adhami H, Sallal Z, Al-Khuzaie M. Synthesis, Antibacterial, Antioxidant, and In Silico Evaluation of New Sulfamethoxazole-Based Schiff Base and Azo Derivatives. JOTCSA. 2026;2026(2):1-12. doi:10.18596/jotcsa.1947271
Chicago
Ahmed, Khitam, Huda Al-Adhami, Zainab Sallal, and Mohammed Al-Khuzaie. 2026. “Synthesis, Antibacterial, Antioxidant, and In Silico Evaluation of New Sulfamethoxazole-Based Schiff Base and Azo Derivatives”. Journal of the Turkish Chemical Society Section A: Chemistry 2026 (2): 1-12. https://doi.org/10.18596/jotcsa.1947271.
EndNote
Ahmed K, Al-Adhami H, Sallal Z, Al-Khuzaie M (September 1, 2026) Synthesis, Antibacterial, Antioxidant, and In Silico Evaluation of New Sulfamethoxazole-Based Schiff Base and Azo Derivatives. Journal of the Turkish Chemical Society Section A: Chemistry 2026 2 1–12.
IEEE
[1]K. Ahmed, H. Al-Adhami, Z. Sallal, and M. Al-Khuzaie, “Synthesis, Antibacterial, Antioxidant, and In Silico Evaluation of New Sulfamethoxazole-Based Schiff Base and Azo Derivatives”, JOTCSA, vol. 2026, no. 2, pp. 1–12, Sept. 2026, doi: 10.18596/jotcsa.1947271.
ISNAD
Ahmed, Khitam - Al-Adhami, Huda - Sallal, Zainab - Al-Khuzaie, Mohammed. “Synthesis, Antibacterial, Antioxidant, and In Silico Evaluation of New Sulfamethoxazole-Based Schiff Base and Azo Derivatives”. Journal of the Turkish Chemical Society Section A: Chemistry 2026/2 (September 1, 2026): 1-12. https://doi.org/10.18596/jotcsa.1947271.
JAMA
1.Ahmed K, Al-Adhami H, Sallal Z, Al-Khuzaie M. Synthesis, Antibacterial, Antioxidant, and In Silico Evaluation of New Sulfamethoxazole-Based Schiff Base and Azo Derivatives. JOTCSA. 2026;2026:1–12.
MLA
Ahmed, Khitam, et al. “Synthesis, Antibacterial, Antioxidant, and In Silico Evaluation of New Sulfamethoxazole-Based Schiff Base and Azo Derivatives”. Journal of the Turkish Chemical Society Section A: Chemistry, vol. 2026, no. 2, Sept. 2026, pp. 1-12, doi:10.18596/jotcsa.1947271.
Vancouver
1.Khitam Ahmed, Huda Al-Adhami, Zainab Sallal, Mohammed Al-Khuzaie. Synthesis, Antibacterial, Antioxidant, and In Silico Evaluation of New Sulfamethoxazole-Based Schiff Base and Azo Derivatives. JOTCSA. 2026 Sep. 1;2026(2):1-12. doi:10.18596/jotcsa.1947271