International Journal of Drug Delivery Technology
Volume 16, Issue 13s, 2026

Design, Synthesis, and Structure-Activity Relationship Study of Thiadiazole-Linked Phenylquinazolinone-β-Lactam Hybrids as Potent Antimicrobial Agents

Vikas Kumar1, Sandeep Kumar Tyagi1, Deepa Sharma1

1Department of Basic Science, School of Sciences, IIMT University Meerut-250001 (U.P.), India

Corresponding Author: dude.vikaskumar@gmail.com


ABSTRACT

Background: The antimicrobial effect of a novel series of thiadiazole-linked phenylquinazolinone derivatives that incorporate Schiff base and β-lactam pharmacophores (8–17) was rationally designed, synthesized, and assessed. The quinazolinone scaffold was hybridized with azetidinone and thiadiazole motifs as part of the molecular design strategy to increase biological potency through synergistic structural features.

Methods: Mass spectrometry, elemental analysis, ¹H NMR, and infrared spectroscopy were used to fully characterize all produced compounds. Gram +ve (B. subtilis, S. aureus), Gram -ve (E. coli), and fungal strains (C. albicans, A. niger, C. krusei) were used to evaluate the antimicrobial potential in vitro. With clear structure–activity relationships, a number of derivatives showed strong antibacterial and antifungal activity.

Results: Specifically, β-lactam analogues with electron-donating aromatic substituents. With low minimum inhibitory concentration of 1.56–6.25 µg/mL across several microbial strains, compound 16 was found to be the most active derivative. Its activity was comparable to that of conventional reference medications. Analysis of the structure–activity relationship showed that steric factors, hydrogen-bonding capacity, and electronic effects are important in regulating the effectiveness of antibiotics.

Conclusion: These results show that thiadiazole–quinazolinone–β-lactam hybrids are promising lead structures for the creation of novel antimicrobial drugs.

Keywords : phenylquinazolinone, azetidinone, thiadiazole, antibacterial activity, antifungal activity.

How to cite this article: Kumar V, Tyagi SK, Sharma D. Design, Synthesis, and Structure-Activity Relationship Study of Thiadiazole-Linked Phenylquinazolinone-β-Lactam Hybrids as Potent Antimicrobial Agents. Int J Drug Deliv Technol. 2026;16(13s): 356-364. DOI: 10.25258/ijddt.16.13s.38

Source of support: Nil.

Conflict of interest: None