Exploring the Antimicrobial Potential of 1,3,4-Oxadiazole Derivatives: Synthesis, Characterization, and Activity Against Clinically Significant Pathogens

İbrahim Pınar; Yamaç Tekintaş; Burak Kuzu

doi:10.52794/hujpharm.1782013

Exploring the Antimicrobial Potential of 1,3,4-Oxadiazole Derivatives: Synthesis, Characterization, and Activity Against Clinically Significant Pathogens

Abstract

The 1,3,4-oxadiazole ring is a structurally stable and pharmacologically active scaffold widely explored in drug discovery. This study presents a practical synthetic approach for 2,5-diaryl-substituted 1,3,4-oxadiazole scaffolds and evaluates their antimicrobial and antibiofilm potential. A total of 14 novel compounds were synthesized and screened for antibacterial activity against four clinically relevant bacterial strains: Staphylococcus aureus (ATCC 25923), Enterococcus faecalis (ATCC 29212), Escherichia coli (NCTC 13846), and Salmonella enterica (RSKK 04059). Minimum inhibitory concentrations (MICs) were determined in micromolar (μM) ranges, and several compounds demonstrated promising antibacterial effects. Among them, compounds 11h and 11i were selected for further evaluation of antibiofilm activity. Both compounds significantly inhibited biofilm formation by S. aureus, E. faecalis, and S. enterica, even at concentrations below their MIC values. A dose-dependent inhibition profile was observed, indicating potential utility in targeting bacterial biofilms at low doses. Interestingly, no antibiofilm activity was observed against E. coli NCTC 13846; instead, biofilm formation appeared to increase at certain concentrations. In summary, the synthesized 1,3,4-oxadiazole derivatives, particularly 11h and 11i, exhibited promising antimicrobial and antibiofilm activities, indicating their potential as core scaffolds for the design of new therapeutic agents targeting resistant bacterial strains.

Keywords

Project Number

TLO-2024-11247

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Details

Primary Language

English

Subjects

Pharmaceutical Chemistry

Journal Section

Research Article

Authors

İbrahim Pınar
0009-0003-7635-9829
Türkiye

Yamaç Tekintaş
0000-0001-9437-7527
Türkiye

Burak Kuzu ^*
0000-0002-7305-7177
Türkiye

Publication Date

June 1, 2026

Submission Date

September 11, 2025

Acceptance Date

April 21, 2026

Published in Issue

Year 2026 Volume: 46 Number: 2

DOI

https://doi.org/10.52794/hujpharm.1782013

IZ

https://izlik.org/JA58DS87GH

Cite

RIS / Bibtex

APA

Pınar, İ., Tekintaş, Y., & Kuzu, B. (2026). Exploring the Antimicrobial Potential of 1,3,4-Oxadiazole Derivatives: Synthesis, Characterization, and Activity Against Clinically Significant Pathogens. Hacettepe University Journal of the Faculty of Pharmacy, 46(2), 99-111. https://doi.org/10.52794/hujpharm.1782013

AMA

1.Pınar İ, Tekintaş Y, Kuzu B. Exploring the Antimicrobial Potential of 1,3,4-Oxadiazole Derivatives: Synthesis, Characterization, and Activity Against Clinically Significant Pathogens. HUJPHARM. 2026;46(2):99-111. doi:10.52794/hujpharm.1782013

Chicago

Pınar, İbrahim, Yamaç Tekintaş, and Burak Kuzu. 2026. “Exploring the Antimicrobial Potential of 1,3,4-Oxadiazole Derivatives: Synthesis, Characterization, and Activity Against Clinically Significant Pathogens”. Hacettepe University Journal of the Faculty of Pharmacy 46 (2): 99-111. https://doi.org/10.52794/hujpharm.1782013.

EndNote

Pınar İ, Tekintaş Y, Kuzu B (June 1, 2026) Exploring the Antimicrobial Potential of 1,3,4-Oxadiazole Derivatives: Synthesis, Characterization, and Activity Against Clinically Significant Pathogens. Hacettepe University Journal of the Faculty of Pharmacy 46 2 99–111.

IEEE

[1]İ. Pınar, Y. Tekintaş, and B. Kuzu, “Exploring the Antimicrobial Potential of 1,3,4-Oxadiazole Derivatives: Synthesis, Characterization, and Activity Against Clinically Significant Pathogens”, HUJPHARM, vol. 46, no. 2, pp. 99–111, June 2026, doi: 10.52794/hujpharm.1782013.

ISNAD

Pınar, İbrahim - Tekintaş, Yamaç - Kuzu, Burak. “Exploring the Antimicrobial Potential of 1,3,4-Oxadiazole Derivatives: Synthesis, Characterization, and Activity Against Clinically Significant Pathogens”. Hacettepe University Journal of the Faculty of Pharmacy 46/2 (June 1, 2026): 99-111. https://doi.org/10.52794/hujpharm.1782013.

JAMA

1.Pınar İ, Tekintaş Y, Kuzu B. Exploring the Antimicrobial Potential of 1,3,4-Oxadiazole Derivatives: Synthesis, Characterization, and Activity Against Clinically Significant Pathogens. HUJPHARM. 2026;46:99–111.

MLA

Pınar, İbrahim, et al. “Exploring the Antimicrobial Potential of 1,3,4-Oxadiazole Derivatives: Synthesis, Characterization, and Activity Against Clinically Significant Pathogens”. Hacettepe University Journal of the Faculty of Pharmacy, vol. 46, no. 2, June 2026, pp. 99-111, doi:10.52794/hujpharm.1782013.

Vancouver

1.İbrahim Pınar, Yamaç Tekintaş, Burak Kuzu. Exploring the Antimicrobial Potential of 1,3,4-Oxadiazole Derivatives: Synthesis, Characterization, and Activity Against Clinically Significant Pathogens. HUJPHARM. 2026 Jun. 1;46(2):99-111. doi:10.52794/hujpharm.1782013